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qui phm ni

Rules for Floating Docks

chng 1 qui nh chung

1.1 Qui nh chung

1.1.1 Phm vi p dng

1 Vic kim tra v ng mi cc ni phi tha mn Qui phm ny.

2 Qui phm ny xy dng trn c s coi ni ch chu ti trng ph hp v ch lm vic trong vng nc cbo v; khng p dng cho trng hp c s tp trung hoc phn b ti trng c bit. ng kim c th yucu gia cng b sung i vi ni bt k, m theo kin ca ng kim, c th phi chu ng sut ln doc tnh ring khi thit k hoc do ni c thit k theo iu kin ti trng hoc dn khc thng. Trongcc trng hp ny, cc ti liu tnh ton phi c trnh cho ng kim xt duyt.

3 i vicc kt cu, my v trang thit b quan trng cha c qui nh Qui phm ny, phi p dng ccqui nh lin quan ca TCVN 6259 : 2003 "Qui phm phn cp v ng tu bin v thp" (t sau y c gitt l Qui phm ng tu").

1.1.2 Thay th tng ng

Kt cu thn ni, trang thit b, b tr v kch thc c cu khc so vi nhng qui nh Qui phm ny cth c ng kim chp nhn vi iu kin chng minh c rng kt cu thn ni, trang thit b, b tr vkch thc c cu y tng ng vi nhng yu cu Qui phm ny.

1.1.3 Cc qui nh khc

Ngoi nhng qui nh v phn cp v ng mi cc ni Qui phm ny, ch tu, nh my ng tu vngi thit k phi tun theo cc qui nh ca nh nc hay chnh quyn a phng hoc ca cc t chckhc v an ton, v sinh lao ng hoc cc tiu chun khc p dng cho ni.

1.1.4 Giy chng nhn lai dt

Khi ch tu, nh my ng tu ngh ng kim cp Giy chng nhn lai dt cho ni hnh trnh trn binth bn, mn kh, n nh v cc phn khc c th c ng kim xem xt c bit, nu cn.

1.1.5 Cn trc

Khi nh my ng tu hoc ch tu ngh xc nh ti trng lm vic an ton ca cn trc, ng kim s tinhnh xc nh ti trng lm vic an ton ca cn trc theo TCVN 6272 : 2003 - " Qui phm thit b nng hngtu bin".

1.2 nh ngha

1.2.1 Chiu di

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Chiu di (L) l khong cch, mt, gia cc mt ngoi ca vch trc v vch sau ca kt cu phn ni ca ni o trn ng nc ng vi trng thi khi ni nng mt con tu c lng chim nc bng sc nng ca ni.

1.2.2 Chiu rng

Chiu rng (B) l chiu rng thit k, mt, o ti khong cch ln nht theo phng ngang gia hai mt phatrong ca tn mn ngoi cng.

1.2.3 Chiu cao

Chiu cao (D) l chiu cao thit k, mt, o ti mt phng dc tm t mt trn ca tn y n mt di catn boong nc.

1.2.4 Boong an ton

Boong an ton l boong kn nc bao ph trn ton b chiu di ca cc vch mn v nm di boong nc.

1.2.5 Boong nc

Boong nc l boong bao ph trn ton b chiu di ca cc vch mn to thnh nh ca cc vch mn.

1.2.6 Png tng

Png tng l phn kt cu ca ni gia cc vch mn, i t y ni n mt di ca vch mn.

1.2.7 Nc ng

Nc ng l nc khng th dng bm ht ra khi cc khoang dn.

1.2.8 Nc dn b

Nc dn b l nc dn dng gim ng sut v bin d ng trong kt cu ni v dng iu chnh nghing v chi ca ni.

1.2.9 Sc nng ca ni

Sc nng (Q) l lng chim nc ca ni xc nh c trng thi nng con tu nng nht d kin trongiu kin lm vic bnh thng.

1.2.10 Lng chim nc khng ti

Lng chim nc khng ti ca ni l trng lng ton b ca bao gm ton b cc my mc, cn trc,trang thit b, ton b d tr phc v hot ng ca ni (nhin liu, nc ngt, v.v...), nc dn b (nu cn)v nc ng.

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(1) Kim tra vt liu v trang thit b theo qui nh Phn 7A v 7B ca Qui phm ng tu;(2) Kim tra qui trnh hn v kim tra ng hn bng chp nh phng x theo qui nh Phn 6 ca Qui

phm ng tu;(3) Kim tra ca ng kim vin trong phn xng, khi lp rp phn on hoc tng on;(4) Kim tra khi mt phn ca ni c hon thnh;

(5) Kim tra khi tin hnh th theo qui nh 2.1.4.

2.1.4 Th nghim

Trong qu trnh kim tra phn cp, cc th nghim sau y phi c tin hnh:

(1) Th khoang ktTt c cc khoang kt k c khoang trng v khoang cch ly phi c th ring bit vi ct nc nim cao nht m khi ni lm vic nc s dng ln ti. Nu kch thc c cu trn vch bin ca ktc xc nh da trn chnh lch ct p lm vic ln nht th ct p th khng cn ln hn chnh lch ctp lm vic thit k. Th bng kh hoc th bng vi phun nc c th c coi l tng ng vi quinh trn nu trnh ng kim duyt tt c cc chi tit lin quan cn thit.

(2) Th kt thcSau khi ng xong , cc th nghim phi c tin hnh xc nh:(a) Mn kh n boong nc khi nh chm ni;(b) Lng chim nc khng ti v sc nng ca ni ng vi mn kh ti thiu;(c) V tr trng tm bng th nghing ngang;(d) Nhng bin dng do ng mi trng thi ban u. Trng thi ban u l trng thi m tt c cc kt

d tr (nc ngt, du t, v.v...) c cha y nhng tt c cc kt khc th rng, ch c nc ngvn gi trong cc kt dn. Cc cn cu di ng c th ng yn nhng v tr to ra chiu chm bngnhau pha trc v pha sau;

(e) chia chnh xc ca thit b o vng ca ni bng cch gi nh trng thi c ti d kin cngst thc cng tt.

(3) Th cc h thngCc bm ca h thng my mc, thit b iu khin t ng/iu khin t xa ng ng v h thng chachy phi c th ti ni ch to tha mn yu cu ca Qui phm ng tu. Tuy vy, ng kim c thb qua bc kim tra bi ng kim vin ti nh my ch to, nhng phi trnh ng kim Giy chngnhn ca nh my ch to v phi th hot ng c s tham gia ca ng kim vin sau khi lp t. Tt ccc my mc v h thng lin quan n phn cp ca ni phi c th hot ng sau khi lp t vi schng kin ca ng kim vin.

(4) Thit b inCc th nghim v kim tra sau y phi c tin hnh i vi thit b in sau khi c lp t ln ni:(a) o in tr cch in;

(b) Th hot ng ca thit b in chnh;(c) Cc th nghim v kim tra khc m ng kim thy cn thit.

2.2 Kim tra phn cp cc ni c ng mi khng qua gim st ca ng kim

2.2.1 Trnh bn v v h s

Cc bn v ghi r kch thc v b tr ca cc kt cu chnh ca ni hin c v cc h s qui nh 2.1.2phi c trnh ng kim xt duyt. Cc bo co v bin bn lin quan n kt cu ca cng phi cgi cho ng kim khi c yu cu.

2.2.2 Kim traTrong mi trng hp, ton b cc qui nh 2.3.3 phi c thc hin. Trong sut qu trnh kim tra, ngkim vin phi xem xt s tha mn v cht lng cng ngh v xc nhn kch thc ca cc c cu v trang

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thit b theo cc h s duyt. xc nhn thc trng ca bt k h hng no, nu cn, cc phn ca kt cu

phi c khoan kim tra. ni c hnh thc kt cu mi phi c xem xt c bit.

2.3 Kim tra chu k v kim tra bt thng

2.3.1 Qui nh chung1 duy tr cp, ni phi c tin hnh kim tra chu k, kim tra bt thng (kim tra khi s c, sa cha,

hon ci v trang b li, v.v...) v kim tra trn ph hp vi nhng qui nh 2.3.2 n 2.3.4 di y.

2 Nu khng c qui nh no khc 2.3 ca Chng ny, nhng qui nh c lin quan n ni Phn 1-B caQui phm ng tu phi c p dng.

2.3.2 Kim tra trung gian

1 Kim tra trung gian phi c thc hin vo t kim tra hng nm ln th 2 hoc ln th 3 sau khi kim traphn cp hoc sau ln kim tra nh k trc (xem 1.1.3 v 3.3 Phn 1B ca Qui phm ng tu).

2 Trong mi ln kim tra trung gian, cc b phn sau y phi c kim tra v phi trng thi tt.

(1) Png tng, boong nc v boong an ton, tn vch mn nm pha trn ng nc khng ti, tn gia y,cc hp mn v cc b hp mn.

(2) ng thng gi, ng trn, ng thng kh i xung pha di cc boong to thnh m kh v cc ca xmn.

(3) Hnh lang i li, cu thang v lan can cng nh cc phng tin bo v cn thit khc i n tt c cckhng gian.

(4) H thng ch bo bin dng thn ni(5) B tr h thng phng chy v cha chy(6) My mc, bm v cc trang thit b khc.

3 Ni hi phi c kim tra vo mi t kim tra trung gian theo qui nh 3.8Phn 1B ca Qui phm ngtu.

2.3.3 Kim tra nh k

1 Kim tra nh k phi c thc hin 5 n mmt ln trong vng 3 thngtrc hoc vo ngy ht hn ca giychng nhn phn cp (c th theo yu cu 1.1.3 Phn 1B ca Qui phm ng tu). Nu c ng kimchp nhn, kim tra nh k c th c li li ti a 3 thngsau ngy ht hn ca giy chng nhn phn cp.

2 Kim tra nh k phi ng thi tha mn tt c cc yu cu i vi kim tra trung gian v qua kim tra, ngkim vin phi xc nhn c rng tt c phng tin bo v cc l khot u trng thi tt v d tip cn.Cng vic kim tra phi c tin hnh theo nhng qui nh sau y:

(1) Png tng v cc kt mn phi c v sinh, kim tra bn trong v ncc th phi tha mn yu cuca ng kim vin. Theo s tha thun vi ng kim vin, cc kt du t t o thnh mt phn ca ktcu chnh c th khng cn thit phi kim tra bn trong khi ni cha qu 15 n mtui.

(2) Cc khoang trn boong an ton phi c kim tra bn trong, tho lp bc bo v, v.v... nu cn cho vickim tra. ng ng thng hi i xung pha di boong to thnh m kh cng phi c kim tra.

(3) Nu b mt tn c ph lp xi mng, cht do hoc c bc g th lp ph phi c tho ra nu cnphi kim tra tn bao.

(4) Vi bt c phn kt cu no, nu nhn thy c hin tng mn g, ng kim vin c th yu cu xc nhchiu dy bng phng php c chp nhn. Nu cn th kt cu ny phi c thay mi.

3 Trong ln kim tra nh k sau khi ni c 20 n mtui v ti cc khong thi gian 10 n mt sau tr i,

ngoi nhng qui nh ca -2 trn y, chiu dy ca cc kt cu phi c xc nh bng phng php cng kim chp nhn nh gi tnh trng chung. Hai di o xc nh chiu dy c cu phi c nh ra

trong phm vi 0,4L chiu di gia ca .

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4 Vic kim tra y ngoi pha di ng nc khng ti phi c thc hin vo mi t kim tra nh k.Vic kim tra c th c tin hnh phi hp nh sau:

(1) Nghing ni kim tra phn y.(2) o chiu dy tn bng phng php siu m.(3) Chp nh di nc.

(4) Quay phim di nc.(5) Kim tra bi th ln. gia hn thi hn kim tra di ng nc, ng kim c th tin hnh xem xt c bit tnh trng ca ni.

5 Kim tra ni hi phi ph hp vi cc yu cu 3.8, Phn 1B ca Qui phm ng tu. Vic kim tra my mc,h ng ng, van, bm v thit b in phi ph hp vi nhng qui nh c lin quan 3.7 Phn 1B ca Quiphm ng tu mc c th thc hin c.

2.3.4 Kim tra trn Vic a ni ln kim tra s c xc nh trong tng trng hp c th. Khng ph thuc vo nhngqui nh 3.2 Phn 1B ca Qui phm ng tu, cn c vo tui v tnh trng thc t ca ni, thi gian vkhi lng kim tra trn s c ng kim xem xt v quyt nh trong tng trng hp c th.

2.3.5 H hng, hon ci v trang b li

Khi ch hng hoc tin hnh cng vic hon ci kt cu, my mc hoc trang thit b lm nh hng hoc cth lm nh hng n cp ca ni, ch ni hoc i din ca ch ni phi thng bo mi ng kimvin n kim tra.

2.4 Chun b kim tra v tr gip kim tra2.4.1 Chun b kim tra v tr gip kim tra

1 Ch ni phi thc hin cc cng tc chun b theo yu cu ca kim tra cng nh nhng yu cu m ngkim vin cho l cn thit ph hp vi Qui phm. Cng tc chun b nhm m bo mt li vo an ton v ddng, cc iu kin vt cht v h s cn thit tin hnh vic kim tra. Cc thit b tin hnh kim tra,o c v th nghim m ng kim vin cn tin hnh vic phn cp phi c chn la v kim chunring bit theo tiu chun m ng kim cho l thch hp. Tuy nhin, ng kim vin c th chp nhn nhngthit b o c n gin (nh thc, thc dy, ng h hn, trc vi k) m khng cn s la chn ring l hays xc nhn v kim chun vi iu kin nhng thit b c thit k thng dng t tiu chun v c ichiu nh k vi cc thit b hay dng c th nghim tng t. ng kim vin cng c th chp nhn nhng

thit b c lp t trn mn v nhng thit b c s dng trong qu trnh kim tra thit b trn m n (nh ng h o p sut, nhit hoc vng quay my v cc dng c o) da trn h s kim chun hoc sosnh vi nhng ch s ca cc dng c khc.

2 Ch ni phi b tr mt nhn vin bit r v cc qui trnh kim tra trong cng tc chun b tr gip ngkim vin trong sut qu trnh kim tra.

3 Cng vic kim tra c th b hon li nu cha c s chun b cn thit hay ch ni hoc nhn vin nh yucu mc -2 khng c mt khi tin hnh kim tra hoc ng kim vin thy cha c s m bo an ton chovic tin hnh kim tra.

4 Trong qu trnh kim tra ng kim vin s thng bo nhng ch cn thit phi sa cha cho ngi yu cukim tra trong khuyn ngh ca mnh. Vic sa cha phi c thc hin tha mn yu cu ca ng kim

vin.

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Ch n g 3 b t r c h un g

3.1 Boong an ton

Boong an ton phi c b tr pha di boong nc ti cao sao cho khi tt c cc kt di boong an tonb ngp trng thi khng ti th mn kh t ng nc n boong nc vn m bo yu cu. Cc thit blp trn boong an ton nh m kh, phi c quan tm c bit. Cc boong an ton chu nh hng ca su ca nc khi boong lm vic cng phi c xem xt c bit.

3.2 Boong nc

phi c mt boong nc kn thi tit, kn thi tit trong trng hp ny c ngha l kh nng khng cho nclt vo trong ni, tr nc ma cc l tiu nc.

3.3 Thng hi v li i

Tt c cc kt phi c ng thng hi hoc ng trn. Ming ng thng hi v ng trn phi nm pha trnng nc ng vi chiu chm ln nht khi c nh chm. Trong tt c cc khoang phi b tr cc lngi chui qua li. Cc l khot phi c b tr m bo thng hi thch hp v tip cn c n tt ccc phn ca kt cu .

3.4 Khoang cch ly

Khoang cha du phi c cch ly vi cc khoang cha nc ngt hoc nc sinh hot bng khoang cch ly.

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Chng 4 mn kh v n nh

4.1 Mn kh

4.1.1 Chiu cao mn kh n boong nc

Khi c nh chm n chiu chm ln nht, chiu cao mn kh n boong nc thng thng khng cnh hn 1,0 mt.

4.1.2 Chiu cao mn kh n boong png tng

Mn kh o n boong png tng ca ni trng thi lm vic khi c tu ng vi vi sc nng ca nmtrn cc k khng c nh hn 300 mi-l i -mt ti mt phng dc tm v khng c nh hn 75 mi-l i -mtti vch mn pha trong. Cc cn trc trn c th c t v tr khng c chi.

4.1.3 Chiu cao mn kh ca ni lm vic vng nc khng c bo v

Nu ni lm vic nhng vng nc khng c bo v ngn sng th c th yu cu chiu cao m n khcao hn nhng tr s qui nh 4.1.1 v 4.1.2.

4.2 n nh

4.2.1 Qui nh chung

Nhng qui nh v n nh c nu 4.2.2, 4.2.3 v 4.2.4 di y c p dng cho cc ni hot ng vng nc c bo v. i vi ni hot ng vng nc khng c bo v n nh ca phi ph hpvi qui nh 4.3 Phn 10 n nh - TCVN 6259-10 : 2003 ca Qui phm ng tu.

4.2.2 Chiu cao tm nghing h0

Thng thng chiu cao tm nghing ban u h0 phi khng c nh hn 1,0 mt trong mi iu kin titrng qui nh (1), (2) v (3) di y. Tuy nhin, i vi cc trng thi tm thi trong thi gian ngn, nuc s xem xt ring trong tng trng hp c th, c th chp nhn tr s chiu cao tm nghing h0 nh hn.

(1) ni ngp ton b n mn kh nh nht tnh n boong nc.(2) ni c png tng ngp nc n mc thp hn nh ca hng k gia, c tu t th bt li nht trn

k ca , v vic ly li thng bng cho t hp /tu theo mt nc ch c thc hin bng kt mnca .

(3) ni trng thi lm vic ti a theo thit k c tu in hnh nm trn k ca , k c trng hp bt

li nht.

4.2.3 th n nh tnh

th n nh tnh bao gm c ng cong m men nghing do gi phi c trnh duyt i vi trng thithit k 4.2.2 (3).Thng thng im giao nhau gia ng cong n nh tnh v ng cong m men nghing do gi trong btk trng hp no cng khng c ln hn gc m bt k phn no ca boong png tng nhng nc.

4.2.4 M men nghing do gi

M men nghing do gi c th c tnh ton theo cng thc sau :

Mv = 0,625 10-4 Vg

2A vZ1 (t.m )

Trong :

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Av:Din tch hnh chiu theo chiu dc ca b mt hng gi c xt n tt c phn din tch hng ginghing ca tu trn (m2).

Z1 = Z +2

1d (m)

Z:Khong cch thng ng t trng tm ca Avn ng nc ca (m).

d:Chiu chm ca (m).

Vg: Tc gi (m/s), tc gi thng thng khng c nh hn 25 m/s. Tuy nhin, tr s tc gi cn ph thuc vo vng hot ng v phng thc hot ng ca , tr s ny c th cxem xt c th hn trong tng trng hp.

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Ch n g 5 kt c u th n

5.1 Qui nh chung

5.1.1 Vt liu

1 Nhng qui nh Chng ny p dng cho c kt cu ch yu bng thp cn dng cho kt cu thn tu quinh Phn 7A V t l i u ca Qui phm ng tu hoc tng ng. Nu s dng thp c bn cao, kt cuca phi tha mn yu cu ca ng kim.

2 Thp c cp A hoc tng ng qui nh Phn 7A ca Qui phm ng tu c th c dng lm cc kt cuchnh ca thn . Tuy nhin, thp cp D hoc tng ng phi c dng lm cc c cu chnh nh tnboong, tn bao v cc sng dc trn nhng tm tn ny trong phm vi 0,4L chiu di gia , nu chng cchiu dy ln hn 30 mi-l i -mt.

3 Nu ni hot ng vng m nhit khng kh v ma ng di 0 oC th dai va p ca thp phi

c xem xt c bit.

5.1.2 Hn

Hn v mi ni hn phi tha mn cc yu cu Phn 6 H n ca Qui phm ng tu mc c th ci vi ni. C th hn theo tiu chun c cng nhn khc vi iu kin tt c cc qui nh c lin quanca tiu chun y tha mn Qui phm.

5.1.3 Chng n mn

Tt c cc mt pha trong v pha ngoi ca kt cu thn , tr kt cha du, phi c bo v chng n mnbng cch sn hp cht thch hp hoc bng cc phng php hu hiu khc. Nu dng lp ph bo v c

bit cho mt pha trong v pha ngoi, hoc cc phng php chng n mn c bit c chp nhn khc,vic gim kch thc c cu s c xem xt ring.

5.1.4 Kt cu chung

1 Cc yu cu trong Chng ny c p dng cho ni bng thp thuc cc dng sau y :

(1) Dng hp kn nc ln: c png tng y lin tc v hp mn hai bn tch ri(2) Dng png tng lp ghp c : gm hp mn hai bn lin tc v y gm cc png tng tho ri

c. Png tng ny c ni vi hp mn c nh hoc tho ri c.

2 trnh s tp trung ng sut qu ln, cc kt cu ca phi c ko di lin tc n mc c th dc.

5.2 bn dc

5.2.1 bn dc

bn dc ca ni phi c tnh ton cho cc trng thi nguy him nht khi a tu vo v trng thichuyn tip khi hot ng bnh thng. Trang thi nh vy thng thng c gi nh l tr ng thi nng tu

c trng lng bng sc nng ln nht ca . Chiu di tu nh nht ( Ls) ca tu coi rng c trn cc k dc tm . Tm ca chiu di tu c t ti gia chiu di , v mn kh ti boong png tng ly nh

qui nh 4.1.2. Mc nc dn khng thay i trn sut chiu di (L). Tuy nhin, mc nc dn b c thc xc nh theo Bn hng dn vn hnh , trong d kin rng ho t ng bnh thng ca phi l

cc trng thi dn thch hp c tha thun vi ng kim.

5.2.2 Trng thi ko

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Nu mun ko i trong vng nc khng c bo v th bn dc ca phi c xem xt c bit, baogm c cc c tnh v ma, thi gian v vng nc m s c ko qua.

5.2.3 ng cong trng lng tu

ng cong trng lng tu c th c ly theo mt hnh ch nht sao cho ng parabn trm ln c mt

na ca din tch hnh ch nht ny vi chiu di ca c hnh ch nht v hnh parabn u bng Ls.

5.2.4 ng sut cho php

i vi cc trng thi ti trng qui nh 5.2.1 ng sut un dc khng c ln hn 14,5 kg/mm2 v ng sutct phi khng c ln hn 10 kg/mm2.

5.2.5 M un chng un tit din ngang thn

Khi tnh ton m un chng un tit din ngang thn , phi k n din tch tit din ca tt c c cu lin tctham gia bn dc. M un chng un tit din ngang thn gia chiu di phi c xc nh trong

phm vi 0,4L chiu di gia , tr khi phi m rng phm vi xc nh hoc c s gia cng c bit th cnphi c biu m men un.

5.2.6 Cng thc gn ng xc nh m un chng un

Khng ph thuc vo cc qui nh 5.2.1, 5.2.3 v 5.2.4, m un chng un tit din ngang ca thn nichung c th c xc nh theo cng thc sau nu nh sc nng ca khng ln hn 40.000 tn.

Z= 2,35QL (cm3)Trong :

Q: Sc nng ln nht (tn).

5.2.7 Bn hng dn vn hnh

Cc thng tin v cc trng thi ti trng nh hng n bn dc phi c nu trong Bn hng dn vnhnh. Nu m men un v/ hoc lc ct iu chnh c th xut hin tr ng thi c sc nng nh hn sc nngti a th trng thi y phi c xt n v a vo Bn hng dn vn hnh.

5.2.8 Kim sot bin dng

Bin dng cho php ln nht ca thn phi c trnh ng kim xt duyt. Bin dng cho php ln nht cathn khng c ln hn bin dng thn khi nng tu qui nh 5.2.1 ng vi ng sut 14,5 kg/mm2. Vkim sot bin dng ca thn , xem 6.2.

5.3 bn ngang

5.3.1 Trng thi ti trng

bn ngang ca phi c tnh ton cho cc trng thi qu v trng thi a tu vo c coi l nguyhim nht trong hot ng bnh thng ca v phi kim tra bn ngang ca ti thiu l i vi cc trngthi sau:

(1) Cc trng thi a tu vo nh qui nh 5.2.1 vi gi thit rng tu trn ch c t trn cc k dc tm.

(2) Trng thi qu , trng thi ni ln, c tu in hnh nm ton b trn k ca v boong png tngchu tc dng ca ct nc bng mt trn ca k, ng thi c nc dn tng ng trong cc kt.

5.3.2 ng sut cho php

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cc trng thi ti trng qui nh 5.3.1 tr s ng sut ko hoc nn trong cc c cu ngang khng c

vt qu 17 kg/mm2. ng sut ct trong cc c cu ngang khng vt qu 10 kg/mm2.

5.3.3 Cng thc gn ng

Nu sc nng ln nht ca khng ln hn 40.000 tnth vic tnh ton sc bn ngang c th khng cn xtn nu chiu dy ca tn y v tn nc ca png tng khng nh hn tr s xc nh sau y:

(1) Dng hp kn nc lin: Tr s chiu dy ca cc tm ni trn c xc nh theo cng thc sau :

0,0047B2 (mm)

(2) Dng png tng lp ghp c : Xc nh theo cng thc trn hoc tnh theo cng thc sau, ly gi tr noln hn.

0,033Ql

Ld

p

p

(mm)

Trong :

Q: Sc nng ln nht (tn).

lp : Chiu di png tng n nguyn o dc theo ng tm ca (m).dp: Chiu cao ca png tng ti gia (m).

5.4 Chi tit kt cu v bn cc b

5.4.1 B tr kt cu

Sng dc t mt phng dc tm hoc c cu dc phi bn lm ta cho cc k dc tm. Ccsng ph hoc cc c cu ngang phi c t cc k hai bn mn.

5.4.2 bn n nh

Cc tm v chi tit kt cu ca thn phi c gia cng thch ng trnh mt n nh.

5.4.3 Tn bao v tn thnh kt

Chiu dy ca tn bao v tn thnh kt phi khng nh hn tr s xc nh theo cng thc sau. Tuy nhin,chiu dy ti thiu ca tn thnh kt phi bng 6,5 mi-l i -mt, chiu dy ti thiu ca tn bao phi bng 7 mi-li-mt.

3,6S h + 2,5 (mm)Trong :

S: Khong cch ca cc np, sn, v.v..., (m).

h= 2,5 mthoc c xc nh nh sau, ly gi tr no ln hn.i vi kt :Khong cch thng ng o t mp di ca tm tn n trung im ca khong cch t nc ktn nh ng trn (m), c th thay bng chnh lch ct p ln nht ca cc kt dn qui nh 5.4.7.i vi khoang cch ly v khoang trng :Khong cch thng ng o t mp di ca tm tn n ng nc ngp ln nht (m).

5.4.4 Np gia cng kt v sn

M un chng un tit din ca cc np ca kt v sn phi khng nh hn tr s xc nh theo cng thc

sau :

6,65 CShl2 (cm3)Trong :

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S: Khong cch ca np, sn, v.v..., (m).l : Nhp ca cc np, sn, v.v..., (m).h= 2,5 mhoc c xc nh nh sau, ly gi tr no ln hn.

i vi kt:

Khong cch thng ng o t trung im ca li vi np ng v trung im ca Si vi npnm n trung im khong cch t nc kt n nh ng trn (m), c th thay bng chnh lch ctp ln nht ca cc kt dn qui nh 5.4.7.i vi khoang cch ly v khoang trng:

Khong cch thng ng o t trung im ca l i vi sn ng v trung im ca Si visn dc n ng nc ngp ln nht (m).

C: H s c cho Bng 5.1, ph thuc vo dng ca lin kt mt.

Bng 5.1 Tr sC

Mt u ca npu kia ca np

Lin kt bng m Lin kt hn ta hoc bng sng T doLin kt bng m 0,70 0,85 1,30

Lin kt hn ta hoc bng sng 0,85 1,00 1,50

T do 1,30 1,50 1,50

5.4.5 Sng dc, sn khe, v.v...

1 M un chng un tit din ca sng dc, sn khe, v.v..., np ca kt hoc sn khng c nh hntr s tnh theo cng thc sau :

7,13Shl2 (cm3)Trong :

S: Chiu rng din tch c bi sng dc, sn khe, v.v..., (m).l : Chiu di nhp ca sng hoc sn khe,v.v... (m)h= 2,5 mhoc c xc nh nh sau, ly gi tr no ln hn.

i vi kt:

Khong cch thng ng o t trung im ca li vi sng ng, v.v... hoc trung im ca Sivi sng nm, v.v... n trung im khong cch t nc kt n nh ng trn (m), c th thaybng chnh lch ct p ln nht ca cc kt dn qui nh 5.4.7.i vi khoang cch ly v khoang trng:

Khong cch thng ng o t trung im ca li vi sng ng, v.v... hoc trung im ca Sivi sng nm, v.v... n ng nc ngp ln nht (m).

2 Chiu dy bn thnh khng c nh hn tr s tnh theo cng thc sau :

10S1 (mm)Trong :

S1: Khong cch ca np gia cng hoc chiu cao tit din bn thnh, ly gi tr no ln hn, (m).

5.4.6 Thanh ging

Din tch tit din thanh ging t gia cc np gia cng, sn, sng v cc sn khe, v.v..., nu c, khngc nh hn tr s xc nh theo cng thc sau:

2,2Sbh (cm2)

Trong :S: Khong cch ca np, v.v... c bi thanh ging (m).b: Khong cch gia trung im ca hai nhp k nhau ca np, v.v... c bi thanh ging (m).

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h: Ct p ln nht (m), c xc nh tng ng theo yu cu 5.4.4 hoc 5.4.5.

5.4.7 Chnh lch ct p ln nht

Nu chnh lch ct p ln nht c dng lm c s thit k cc kt dn th cc s liu thy tnh cho bitchnh lch ct p da trn cc mc cao nht m nc s dng ln mi bn ca c cu trong khai thc phic trnh duyt. Chnh lch ct p dng khi thit k phi c xc nh gii hn thch hp theo chnh lchct p thc t trong khai thc. Cc s liu cn thit vn hnh nm trong gii h n thit k nh vy phic a vo Bn hng dn vn hnh.

5.4.8 Boong nc

1 Chiu dy ca tn boong nc phi khng nh hn tr s xc nh t cng thc sau hoc 7 mi-l i -mt, ly gi trno ln hn.

10S (mm)Trong :

S: Khong cch x boong (m).2 M un chng un tit din ca x boong nc phi khng nh hn tr s xc nh t cng thc sau:

CS l2 (cm3)Trong :

C= 14,5 vi x dc nm trong phm vi 0,4L chiu di gia , 5,4 i vi x ngang v x dc mttrc v mt sau ca . i vi cc x dc khc vi x nu trn, C c th gim dn t 14,5xung 5,4.

S: Khong cch ca x (m).l: Nhp ca x (m).

3 M un chng un tit din ca sng ngang boong nc phi khng nh hn tr s xc nh theo cng thc sau:6,1bl2 (cm3)

Trong :

b: Khong cch gia trung im ca hai nhp x k nhau c bi sng (m).l : Nhp ca sng (m).

5.4.9 Boong an ton

1 Kch thc c cu ca boong an ton c kt cu nh cc kt phi tha mn cc yu cu 5.4.3, 5.4.4 v 5.4.5.

2 Kch thc c cu ca boong an ton c kt cu khc vi kt phi tha mn cc yu cu sau y:

(1) Chiu dy ca tn boong phi khng nh hn 6,5 mi-l i -mthoc tr s xc nh theo cng thc sau:

3,9 S h + 2,5 (mm)Trong :

S: Khong cch x (m).h: Ti trng boong (tn/m2).

(2) M un chng un tit din ca x boong phi khng nh hn tr s tnh theo cng thc sau:

4,2Shl2 (cm3)Trong :

S: Khong cch x (m).

h: Ti trng boong (tn/m2

).l : Nhp ca x (m).

(3) M un chng un tit din ca sng boong phi khng nh hn tr s xc nh theo cng thc sau:

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4,75bhl2 (cm3)Trong :

b: Khong cch gia trung im ca hai nhp k nhau ca x c bi sng (m).l : Nhp ca sng (m).h: Ti trng boong (tn/m2).

5.4.10 Kt cu khng kn nc

Chiu dy bn thnh ca kt cu khng kn nc nh sng gia, sng cnh v ngang c ca png tng vcc vch khng kn nc khng c nh hn tr s xc nh t cng thc sau:

10S1 (mm)Trong :

S1 : Khong cch np (m).

5.4.11 Kt cu k dc tm v k dc tm

k dc tm v kt cu k dc tm thng thng phi c thit k theo ti trng nh sau:

P= 1,5Q/L (tn/m)Trong :

P: Ti trng tc dng ln k dc tm v kt cu k dc tm nm trn sut chiu di ca .Q: Sc nng ln nht ca (tn).

5.4.12 Sn

Ti trng nh nht trn sn hai u phi bng 600 kg/m2, h s an ton khng c nh hn 4.

5.4.13 Cu ng m

Ti trng nh nht trn cu ng m ti hai u phi bng 400 kg/m2, h s an ton khng c nh hn 4.

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Ch ng 6 my mc v t r an g th it b

6.1 My mc

6.1.1 My mc

Cc bnh p lc khng thuc Nhm 3 v my mc quan trng nh ng c lai my pht in v my ph cnthit cho hot ng ca thng thng phi tha mn cc qui nh c lin quan ca Qui phm ng tu.

6.1.2 H thng ng ng

1 H thng ng ng phi c gng tha mn cc qui nh c lin quan ca Qui phm ng tu n mc c th.

2 Ti thiu ni phi c hai bm nc dn. H thng phn phi nc dn phi c b tr sao cho trong trnghp h hng mt bm th bm kia phi sn sng phc v cho tng kt dn.

6.1.3 Thit bi n1 Thit b in phi c lp t sao cho gim n mc thp nht s c do in nh chp, chy, v.v... theo qui

nh Phn 4 ca Qui phm ng tu.

2 Cp in v my pht in phi l loi ph hp vi cc tiu chun hin hnh c ng kim cng nhn vthch hp lm vic an ton v hu hiu trong iu kin mi trng c lp t.

3 Mch in phi c bo v chng qu ti k c chp mch. Thit b bo v phi c kh nng ngt in khimch in b s c, loi tr c s pht trin ca h hng v nguy c gy chy cng nh n nh cng sutcho ngun in dn ng chnh, h chiu sng, thng tin lin lc trong v thit b bo ng.

6.2 H thng chbo

Thit b o bin dng hoc thit b c chp nhn tng t v thit b ch bo mc nc trong kt, chiu chmv chi phi c trang b m bo rng hot ng ca c theo di thch hp.

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Ch n g 7 Ph n g c h y v c h a c h y

7.1 Qui nh chung

Nhng qui nh Chng ny ch p dng cho vic phng v cha chy ni m khng p dng cho phngv cha chy tu nm trn . Cn phi lu n cc yu cu c lin quan theo lut nh ca nh nc ni c s dng. Theo s tha thun vi ng kim, vic tha mn cc yu cu theo lut nh k trn c coi lph hp vi nhng yu cu Chng ny.

7.2 Phng chy

7.2.1 Khu vc sinh hot

Cc bung , trm iu khin v bung phc v phi c b tr sao cho gim c ti a nguy c chy. Cclu phi c lm bng thp hoc vt liu tng ng. Cc hp cht ph boong trn boong to thnh nc cabung my phi l loi khng to ngun tia la.

7.2.2 Bung my

Cc vch bin ca bung my v cu thang bn trong nm di boong nc phi bng thp hoc vt liu tngng.

7.2.3 Sn

Trong cc bung , trm iu khin, bung phc v, bung my, v.v... khng dc s dng sn, vc ni v cccht c Nitrxenlul tng t hoc cc cht d chy khc.

7.3 Cha chy

7.3.1 H thng cha chy

Cc bm cha chy, ng ng i km v h thng cha chy chnh phi c thit k sao cho duy tr c psut ti thiu to c tia nc xa t nht l 12 mtqua cc vi phun k cn c kch thc theo yu cu 7.3.2. H thng cha chy chnh phi c t mi bn thnh . Hai h thng cp nc ring bit phi c

t phc v cho h thng cha chy chnh. t nht mt h thng cp nc phi c ly t b hoc phic ly t bm d phng c ngun cp c lp t trong .

7.3.2 Hng cha chy, ng mm v vi phun

1 S lng v v tr ca hng cha chy phi sao cho t nht hai dng nc khng bt ngun t cng mt hng,mi dng nc phi phun ra t mt on ng mm ring c th a ti bt k phn no ca , tr kt nc dn bt k trng thi lm vic no.

2 cc bung c t my c tng cng sut t 735,5 kWtr ln, phi t hai hng cha chy. Vi cc bungt my c tng cng sut nh hn 735,5 kW, c th chp nhn s dng mt hng cha chy. Nu mt tronghai trng hp nu trn, vic cha chy trong mt khoang nh khng th thc hin c do hn ch v khnggian th hng cha chy theo yu cu c th t ngoi v k vi li vo khoang.

3 Cc ng mm cha chy phi c chiu di a nc n bt k khoang no trong s cc khoang m theoqui nh chng phi phc v. Cc ng mm phi c chiu di khng qu 18 mt km theo ming phun cng knh bng hoc ln hn 12 mi-l i -mt.

7.3.3 u ni b theo mu quc t

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Nn lp t u ni b quc t trn boong nc ca ni nh qui nh 6.2.19, Phn 5 ca Qui phm ng tu cung cp nc cho cc bnh cha chy ca tu ang nm trn thng qua cc bm ca ni.

7.3.4 Bnh cha chy di ng

1 Cc bnh cha chy di ng phi c t trong ni, nhng ni c nguy c chy. Trong khu vc sinh hot,cc bnh cha chy di ng phi c t sao cho c th tip cn v ly c t nht mt bnh t bt k chno ca khu vc sinh hot. Tng s bnh cha chy theo yu cu trong khu vc sinh hot ph thuc vo dunglng ca bnh v cch b tr.

2 Cc bnh cha chy di ng phi c t trong bung my sao cho cng gn vi cc ng c in, bng in,v.v... phc v cho cc bm, ti qun dy, v.v... cng tt. S lng v v tr ca bnh ph thuc vo dung lngv cch b tr bnh cha chy trong khoang.

7.3.5 H thng cha chy bng kh ngt

Nu t h thng phun kh vo bung my phc v cho mc ch cha chy th cc ng dn kh phi cvan iu khin hoc van t ni d tip cn v khng b v hiu ha do chy. Phi c bin phpthch hp ngn chn s xm nhp ngu nhin ca kh vo cc khoang khc.

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Rul es f o r Fl o a t in g Do c ks

Cha pter 1 g en er a l RULES

1.1 General

1.1.1 Application

1 The survey and construction of floating docks are to be in accordance with this Rules.

2 The Rules are framed on the understanding that floating docks will be properly loaded and handled in

sheltered waters; they do not provide for special distributions or concentrations of load. VR may also require

additional strengthening to be fitted in any floating dock which in their opinion, may be subjected to severe

stresses due to particular features in her design or when it is desried to make provision for exceptional loaded

or ballasted conditions. In these cases particulars are to be submitted for consideration.

3 The relevant portions of the Rules for the classif ication and construction of sea-giong steel ships - TCVN6259 : 2003 (hereinafter referred to as Ship Rules) apply to essential constructions, machinery and

equipment not specified in the Rules, as may be required.

1.1.2 Equivalency

Alternative hull construction equipment, arrangement and other tructrural member scantings will be accepted

by VR, provided that VR is satisfied that such construction, equipment, arrangement and scantlings are

equivalent to those required Rules.

1.1.3 Other regulations

While these Rules cover the requirements for the Classification of new docks the attention of owners,builders, and designers is directed to the regulations of national or local governments, which may contain

safety, health, or other standards applicable to the dock.

1.1.4 Towage cer tificate

Where VR's Towage Certificate is requested by a Builder/Owner to enable a dock to be towed at sea special

consideration may be required to be given to the strength, freeboard and stability, and other items as

considered necessary.

1.1.5 Cranes

When the assignment of safe working load of cranes is requested by the builders or the owners, VR will assignthe safe working load in accordance with the "Rules for cargo handling appliances of ships" - TCVN 6272 :

2003.

1.2 Definitions

1.2.1 Length

The length (L) is the distance, in meters, measured on water line when supporting a ship whose displacement

is the lifting capacity between the aft end and the fore end of the bulkheads of the floating structures of the

dock.

1.2.2 Breadth

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The breadth (B) is the moulded breadth, in metres, measured at the greatest horizontal distance between the

inner surfaces of the outer side plating of wing walls.

1.2.3 Depth

The Depth (D) is the moulded breadth, in metres, measured at the centerline from the inner surface of the

bottom plating to the inner surface of the top deck plating.

1.2.4 Safety deck

The safety deck is a watertight deck extending over the length of the wing walls and located below the top

deck.

1.2.5 Top deck

The top deck is the deck extending over the length of the wing walls to form the top of the wing walls.

1.2.6 Pontoon

The pontoon is the structure that extends between and under the wing walls to from the bottom of the dock.

1.2.7 Rest water

The rest water is water which can not be discharged by pumps from ballast compartments.

1.2.8 Compensating ballast water

The compensating ballast water is ballast water for reduction of stresses and deflections in the dock structures

and for adjustment of the trim and heel of the dock.

1.2.9 L if ting capacity

The lifting capacity (Q) is the displacement of the heaviest ship it is, intended that the dock shall lift in normal

service.

1.2.10 L ight displacememt

The light displacement of the dock is its complete weight including all machinery, cranes, equipment, full

supply of consumables for operation of the dock (fuel oil, fresh water etc.), compensating ballast water (if

necessary) and rest water.

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t c v n 6274 : 2003, Chapter 2(5) When tests specified in 2.1.4 are carried out.

2.1.4 Testing

1 In the classification surveys, the following tests are to be carried out:

(1) Tank test

All tanks including those used for void tanks and cofferdams are to be separately tested by a head of water

to the highest point to which the liquid will rise in service. Where the scantlings of a tank boundary are

based on the maximum differential head in service, care is to be taken to ensure test heads do not exceed

the design differential head. On submission of all necessary detail, air test or hose test may be considered

as an alternative to the foregoing.

(2) Completion trials

On the completion of the dock, trials are to be carried out to ascertain:

(a) The freeboard to top deck with the dock flooded.

(b) The light displacement and the lifting capacity of the dock corresponding to the minimum freeboard.

(c) The position of the centre of gravity by an inclining test.

(d) Any built-in permanent deflection in the initial condition. The initial condition is a condition that all

tanks for consumables (fresh water, fuel oil etc.) are completely filled, but all other tanks are empty,only rest-water remaining in the ballast tanks. The travelling cranes may be parked in positions giving

equal draughts forward and aft.

(e) Correct calibration of deflection metres, by simulating the most severe intended loading condition as

far as practicable.

(3) General systems

The machinery pumps, piping remote control/automatic control instrumentation and fire-extinguishing

system are to be tested at the makers in accordance with the Rules for the Survey and Construction of Steel

Ships as applicable. VR may, however, omit the surveys or inspection in the presence of the Surveyor at

the makers, subject to submission of the maker's certificate and satisfactory performance withessesd by

the Surveyor after installation. All machinery and systems relating to the classification of the dock are to

be functionally tested after installation in the presence of the Surveyor.(4) Electrical equipment:

The following tests and inspections are to be carried out for electrical equipment after installation on the

docks.

(a) Insulation resistance test

(b) Operation test of the essential electrical equipment

(c) Other tests and inspections as considered necessary by VR.

2.2 Classif ication survey not build under survey of VR

2.2.1 Submission of plans and documents

Plans showing the main scantlings and arrangements of the actual dock and documents specified in 2.1.1 areto be submitted to VR for approval. Records and reports relating to the construction of the dock should be

submitted as may be required by VR.

2.2.2 Sur vey

In all cases the full requirements of 2.3.3 are to be carried out. During the survey, the Surveyors are to satisfy

themselves regarding the workmanship and verify the approved scantlings and arrangements. For this purpose

and in order to ascertain the amount of any deterioration, parts of the structure will require to be drilled as

necessary. Docks of recent construction will receive special consideration.

2.3 Per iodical survey and occasional survey

2.3.1 General

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1 To retain its class, a dock in normal service is to be subjected to periodical surveys and survey of alternations,

damages and repairs in accordance with the provisions in the following 2.3.2 to 2.3.4.

2 The requirements of Part 1B of "Ship Rules" also apply as may be relevant to docks, unless otherwise

specified in 2.3 of this Chapter.

2.3.2 Intermediate surveys

1 Intermediate Surveys are to be carried out within six months either way of the date 30 monthsafter completion

of the Registration Survey or the previous Special Survey.

2 At each intermediate survey the following parts are to be examined and placed in good condition.

(1) Pontoon, safety and top decks, wing wall plating above the light waterline, keel and side blocks and their

foundations.

(2) Vents and overflow pipes, air pipes extending below decks to form air cushions and overboard scuppers.

(3) Companionways, ladders, and guardrails and other means of protection that might be provided for access

to all spaces.

(4) Deflection indicating system

(5) Arrangement of fire protection and extinguishing.(6) Machinery, pumps and other equipment.

3 The boilers are to be examined at each intermediate survey in accordance with the provisions of 3.8 in Part 1B

of "Ship Rules".

2.3.3 Special survey

1 Special survey are to be carried out within 3 months before or on the expiry date of the Classification

Certificate. Special surveys may be postponed until maximum 3 monthsafter the expiry date, subject to the

approval by VR.

2 Special survey is to include compliance with all Intermediate Survey requirements, and the Surveyor is to

satisfy himself, by examination, that all means of protection to openings are in good condition and are readilyaccessible. Effect is also to be given to the following requirements:

(1) Pontoon and wing wall tanks are to be cleaned, examined internally, and water tested to the satisfaction of

the Surveyor. At the discretion of the Surveyor, fuel oil tanks forming part of the main structure need not

be examined internally until the dock is more than 10 years old.

(2) Spaces above safety deck are to be examined internally, removing linings, etc. where necessary for

inspection. Air pipes extending below deck to form air cushions are also to be examined.

(3) Where the surface of plating is covered with cement, composition, or wood sheathing, the covering is to

be removed as may be required for examination of the plating

(4) The thickness of any part of the structure where wastage is evident may be required by the Surveyor to be

determined by an approved method. Where necessary the structure is to be renewed

3 At the Special Survey after the dock is 20 yearsold, and at 10 years intervals thereafter, in addition to the

requirements of the preceeding -2, the thicknesses of the structure are to be determined by an approved

method to assess the general condition. Two belts of gaugings are to be made within the 0.4L mid-length of

the dock.

4 Survey of the outer bottom below the light waterline is to be carried out at each special survey. The inspection

may be carried out by some combination of:

(1) Heeling of the dock for partial examination of the bottom.

(2) Ultrasonic measurement of plate thickness.

(3) Underwater photography.

(4) Underwater television.(5) Examination by diver.

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t c v n 6274 : 2003, Chapter 2For the extension of intervals of the examination below the waterline, special consideration may be given by

VR taking into account the dock s conditions.

5 Surverys of boilers are to be in accordance with the requirements in 3.8, Part 1B of "Ship Rules". Surveys of

machinery, pipes, valves, pumps, and electrical equipment are to be in accordance with the relevant

requirements in 3.7, Part 1B of "Ship Rules " as far as applicable.

2.3.4 Damage and alteration

Damage or alteration to structure, machinery, or equipment, which affects or may affect classification, is to be

submitted by the owners or their representatives for examination by the Surveyor.

2.4 Preparations for Surveys and Others2.4.1 Preparation for Surveys and Others

1 All such preparations as required for the survey to be carried out as well as those which may be required by

the Surveyor as necessary in accordance with the requirements in the Rules are to be made by the applicant of

the survey. The preparations are to include provisions of an easy and safe access, necessary facilities and

necessary records for the execution of the survey. Inspection, measuring and test equipment, which Surveyors

rely on to make decisions affecting classification are to be individually identified and calibrated to a standard

deemed appropriate by the VR. However, the Surveyor may accept simple measuring equipment (e.g. rulers,

measuring tapes, weld gauges, micrometers) without individual identification or confirmation of calibration,

provided they are of standard commercial design, properly maintained and periodically compared with other

similar equipment or test pieces. The Surveyor may also accept equipment fitted on board a dock and used in

examination of equipment on board a dock (e.g. pressure, temperature or rpm gauges and meters) based either

on calibration records or comparison of readings with multiple instruments.

2 The applicant for the survey is to arrange a supervisor who is well conversant with the survey items intended

for the preparation of the survey to provide the necessary assistance to the Surveyor according to his requests

during the survey.

3 The survey may be suspended where necessary preparations have not been made, any appropriate attendant

mentioned in the previous -2 is not present, or the Surveyor considers that the safety for execution of the

survey is not ensured.

4 Where repairs are deemed necessary as a result of the survey, the Surveyor will notify his recommendations to

the applicant of the survey. Upon this notification, the repair is to be made to the satisfaction of the Surveyor.

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t c v n 6274 : 2003, Chapter 3

Ch a pter 3 GENERAL ARRANGEMENT

3.1 Safety deck

A safety deck is to be fitted at such a height below the top deck that when all tanks below the safety deck are

flooded but with no load on the keel blocks, there is a reasonable freeboard from the top deck to the waterline.

Alternative arrangements to fitting a safety deck, such as the provision of an air cushion, will be given specialconsideration. Special consideration will also be given to the need for a safety deck in relation to the depth of

water in which the deck operates.

3.2 Top deck

The dock is to be provided with a weathertight top deck, weathertight in this case meaning the ability to

exclude water other than that due to rainfall in way of necessary access openings.

3.3 Ventilation and access

All tanks are to have vent or overflow pipes that terminate well above the water line at the maximum draught

when the dock is submerged. All compartments are to be provided with manholes for access and openings areto be arranged to provided adequate ventilation and access to all parts of the structure.

3.4 Cofferdam

Compartments carrying oil are to be separated cofferdams from those carrying fresh or feed water.

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t c v n 6274 : 2003, Chapter 4Cha pt er 4 FREEBOARD AND STABILITY

4.1 Freeboard

4.1.1 Freeboard to top deck

When the dock is submerged to its maximum draught, the freeboard to the top deck is generally not to be lessthan 1.0 m.

4.1.2 Freeboard to pontoon deck

The freeboard to the pontoon deck with the dock in its final working condition with a ship corresponding to

the lifting capacity of the dock on the blocks is not to be less than 300 mmat the centreline and not less than

75mmat the inner wing walls. The dock cranes may be positioned so as to produce no trim.

4.1.3 Freeboard in unshelterd waters

If the dock's port of operation is not shelterd against waves, greater freeboards than given by 4.1.1 and 4.1.2

may be required.

4.2 Stability

4.2.1 General

The requirements for stability specified in 4.2.2, 4.2.3 and 4.2.4 below apply to the docks operating in

sheltered waters. For the docks operating in not sheltered waters, the stability is to be accordance with the

requierements in 4.3, Part 10 Stability of Ship Rules.

4.2.2 Metacentr ic height ho

1 In general, the initial metacentric height ho is not to be less than 1.0 m in any condition of loads as referred toin (1), (2) and (3) below. For transient conditions of short duration, however, a smaller metacentric height ho

may be accepted upon special consideration.

(1) Dock fully submerged to the minimum freeboard to the top deck.

(2) Dock with pontoon immersed to just below top of keel blocks, with the most unfavourable typical ship

supported by the blocks, and restoring water-plane for the combination dock/ship provided only by the

wing walls of the dock.

(3) Dock in fi nal working condition with typical ships on the blocks, including the most unfavourable ship.

4.2.3 Statical stabili ty diagram

The statical stability diagram including wind heeling moment curve is to be submitted for the design conditionof 4.2.2-1(3).

In general, the point of intersection between the statical stability curve and the wind heeling moment curve is

under no circumstance to exceed the angle where any part of the pontoon deck submerges.

4.2.4 Wind heeling moment

The wind heeling moment may be calculated from the following formula:

Mv = 0.625 10-4

Vg2AZ1 (t.m)

Where:

A: the longitudinal projected area of the exposed surface considered at every stage of inclining exposedareas of docked ship (m2).

Z1 =Z+ 1/2 d (m)

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t c v n 6274 : 2003, Chapter 4

Z : Vertical distance from the center of A to the water line of the dock (m).

d : draught of the dock (m).

Vg: Wind velocity (m/sec), the wind velocity is not to be than 25m/sec in general. However, the values of

the wind velocity will depend on the service location and the mode of operation of the dock, and may

be considered more precisely in each case.

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t c v n 6274 : 2003, Chapter 5Cha pt er 5 HULL STRUCTURE

5.1 General

5.1.1 Material

1 This chapter are applied to the docks mainly constructed with the hull structural rolled steels specified in Part7A of "Ship Rules" or equivalent. Where the higher tensile steels are used, its structure is to be to the

satisfaction of VR.

2 Grade A steels specified in Part 7A of "Ship Rules" or equivalent may be used for the main structures of the

hull. Grade Dsteels or equivalent will, however, be required for the main structural members such as the deck

plates, shell plates and their girders within 0.4L amid-length, where the thickness exceeds 30 mm.

3 If the dock is to be operated in a site with air temperatures regularly below 0C in the winter season, the notch

toughness of the steels will be given special consideration.

5.1.2 Welding

Welding and weld connections are to comply with the requirements in Part 6 of "Ship Rules", as far asapplicable to the docks. Alternatively, welding may be in accordance with another recognized standard

provided all related requirements of the standard are also complied with.

5.1.3 Corrosion protection

All external and internal surfaces of the hull structures except oil tanks are to be protected against corrosion by

paint of suitable composition or other effective means. Where special protective coatings are applied to the

external and internal surfaces, or other specially, effective methods of corrosion control are adopted,

reductions in scantlings will be specially considered.

5.1.4 General construction1 The requirements in this chapter are applied to the steel docks of the following types:

(1) Caisson type: dock in which the bottom pontoon and both dock wings are continuous and inseparatable.

(2) Sectional pontoon type: dock in which the dock wings are continuous and the bottom consists of

individual noncontinuous pontoons. The pontoons are permanently or detachably connected to the dock

wings.

2 To avoid the excessive stress concentration, the structural members of the dock are to be continuous as far as

possible.

5.2 Longitudinal str ength

5.2.1 Longitudinal strength

The longitudinal strength of the dock is to be calculated for the most severe expected docking and transient

conditions during normal operations. Such condition may be generally assumed that a ship having a weight

equal to the maximum lifting capacity of the dock and the shortest ship's length ( LS) expected is supported on

the keel blocks, the centre of the ship's length being positioned at the mid-length of the dock, and the

freeboard at the pontoon deck is as described in 4.1.2. The level of water ballast is to be constant over the

length (L). The level of compenstating ballast water may, however, be determined with the normal operation

manual where it is intended that normal operation of the dock is to be by differential ballast conditions by

special agreement with VR.

5.2.2 Towing condition

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t c v n 6274 : 2003, Chapter 5

Special consideration will be given to the longitudinal strength where it is intended to tow the dock in

unprotected waters, including particulars of the season and the duration and area of the towing operation.

5.2.3 Ship weight curve

The weight curve of the ship is to be taken as a rectangle with a superimposed parabola of half the area of the

rectangle, the length of each area being LS.

5.2.4 Permissible stresses

For the loading conditions defined in 5.2.1 the longitudinal bending stresses are not to exceed 14.5 kg/mm2

and the shear stresses are not to exceed 10 kg/mm2.

5.2.5 Section modulus

When calculating the section modulus of the hull structure, the sectional area of all effective continuous

longitudinal strength members are to be included. The section modulus of the hull structure at its mid-length is

to be determined within 0.4L a mid-length of the dock, unless a larger extension or special strengthening is

necessitated by the bending moment curve.

5.2.6 Approximate formula of required section modulus

Notwithstanding the requirements of 5.2.1, 5.2.3 and 5.2.4, the section modulus required for the hull structure

may be generally determined from the formula where the lifting capacity of the dock is not exceeds 40,000

tons.

Z= 2.35 QL (cm3)

Q: The maximum lifting capacity (tons).

5.2.7 Operation manual

Information on the loading conditions for the longitudinal strength is to be contained in the operation manual.

Where governing bending moments and/or shear forces may occur at condition less than the maximum lifting

capacity, such conditions are to be investigated, and contained in the operation manual.

5.2.8 Deflection control

The maximum allowable deflection of the dock is to be submitted to VR for approval. This deflection is not to

exceed that corresponding to a stress of 14.5 kg/mm2 when lifting the ship defined in 5.2.1. As for deflection

monitoring measures, see6.2.

5.3 Transverse strength

5.3.1 Loading condit ion

1 The transverse strength of the dock is to be calculated for the most severe expected docking and transient

conditions during normal operations, and is to be examined at least for the conditions as follows:

(1) The docked ship conditions as described in 5.2.1. It is assumed that the docked ship normally is supported

by the keel blocks only.

(2) The transient condition: the dock emerging out of water with a typical ship fully supported on the blocks

and the pontoon deck subjected to a water head just below top of docking blocks, with corresponding

ballast water in the tanks.

5.3.2 Permissible stress

Under the loading conditions in 5.3.1 the compressive or tensile stresses in transverse members are not to

exceed 17 kg/mm2. The shear stresses in the transverse members are not to exceed 10 kg/mm2.

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t c v n 6274 : 2003, Chapter 55.3.3 Appr oximate formula

1 Where the maximum lifting capacity of the dock does not exceed 40,000 tons, calculations of the transverse

strength may be omitted if the thickness of the top and bottom plates of the pontoon is not less than that given

below:

(1) Caisson type: obtained from the following formula:

0.0047 B2

(mm)

(2) Sectional pontoon type; given by the above or obtained from the following formula, whichever is greater:

0.033Ql

Ld

p

p

(mm)

Where :

Q: The maximum lifting capacity (tons);

lp : Length of the sectional pontoon measured alongside the centre line of the dock (m);

dp: Depth of the pontoon at the centre (m).

5.4 Structur al detail and local str ength

5.4.1 Structural arrangement

A centerline girder or longitudinal member is to provide adequate support for the keel blocks. Side girders or

transverse members are to be arranged to support for the side blocks.

5.4.2 Buckling

The structural panels and members of the hull structures are to be adequately stiffened to prevent buckling.

5.4.3 Tank and shell plates

The thickness of the tank and shell plates is not to be less than that obtained from the following formula. Theminimum thickness is, however, to be 6.5 mmfor the tank plates and 7 mmfor the shell plates.

3.6S h + 2.5 (mm)

Where:

S : Spacing of stiffeners, frames etc., (m);

h= 2.5mor the followings, whichever is greater;

For tanks:

Vertical distance measured from the lower edge of plate to the mid-point of the distance between the

top of tanks and the top of overflow pipes in metres. As an alternative the maximum differential head

defined in 5.4.7 may be used for the ballast tanks.

For cofferdams and void spaces:Vertical distance measured from lower edge of plate to the maximum immersion water line (m).

5.4.4 Tank stif fener and frame

The section modulus of tank stiffeners and frames is not to be less than obtained from the following formula:

6.65CShl2 (cm3)

Where :

S : Spacing of stiffeners, frames etc.(m);

l : Span of stiffeners, frames etc.(m) ;

h = 2.5mor the followings, which ever is greater:

For tanks:Vertical distance measured from the mid-point of l for vertical stiffeners and of S for horizontal

stiffeners to the midpoint of the distance between the top of tanks and the top of overflow pipes in

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t c v n 6274 : 2003, Chapter 5

metres. As an alternative, the maximum differential head defined in 5.4.7 may be used for the ballast

tanks.

For cofferdams and void spaces:

Vertical distance measured from the midpoint of l for vertical frames etc. or Sfor longitudinal frames

etc. to the maximum immersion water line, (m).

C: Coefficient given in Table 5.1, according to the type of end connections.

Table 5.1 Values of C

One end of stif feners

The other end of stif feners

Connection by

brackets

Lug-connection or

supported by girders

End of stiffener

unattached

Connection by brackets 0.70 0.85 1.30

Lug-connection or supported by girders 0.85 1.00 1.50

End of stiffener unattached 1.30 1.50 1.50

5.4.5 Girder , web frame etc.

1 The section modulus of the girders, web frames etc. supporting the tank stiffeners or frames is not to be lessthan obtained from the following formula:

7.13 S hl2 (cm3)

Where:

S : Breadth of the area supported by the girders, web frames etc. (m).

l : Spance of stiffencers, web frames etc, (m)

h= 2.5 mor the followings, which ever is greater:

For tanks:

Vertical distance measured from the mid-point of l for vertical girders etc. or Sfor horizontal girders

etc. to the mid-point of the distance between the top of tanks and the top of overflow pipes in metres.

As an alternative, the maximum differential head defined in 5.4.7 may be used for ballast tanks.For void spaces, cofferdams:

Vertical distance measured from the mid-point of l for vertical girders etc. or Sfor horizontal girders

etc. to the maximum immersion water line in metres.

2 Thickness of web plates is not to be less than that obtained from the following formula:

10 S1 (mm)

Where:

S1 : Stiffener space or depth of web plates, whichever is greater, in metres.

5.4.6 Cross tie

The sectional area of cross ties, where fitted between the stiffeners, frames, girders, web frames etc. is not tobe less than obtained from the following formula:

2.2 Sbh (cm2)

Where :

S : Space of the stiffeners etc. supported by the cross tie (m).

b: Distance between the mid-point of two adjacent spans of stiffeners etc. supported by the cross tie (m)

h : The maximum head to be determined in accordance with the requirements of 5.4.4 or 5.4.5 as

applicable (m).

5.4.7 Maximum differential head

Where the maximum differential head is used for the design basis of the ballast tanks, hydrostatic data is to besubmitted for approval to show the differential head based on the highest levels to which water will rise on

each side of the structure in service. The differential head on the design is to be determined with a suitable

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t c v n 6274 : 2003, Chapter 5margin to an actual differential head in service. Necessary data on operating the dock within such design

limits are to be included in the operating manual.

5.4.8 Top deck

1 Thickness of the top deck plates is not to be less than that obtained from the following formula or 7mm;

whichever is greater:

10 S (mm)

Where:

S : Beam space (m)

2 Section modulus of the top deck beam is not to be less than that obtained from the following formula.

CS l2 (cm3)

Where:

C = 14.5 for longitudinal beam within 0.4L amid-length, 5.4 for transverse beam and longitudinal beam at

the fore and aft end. For longitudinal beam other than the aforesaid, Cmay be gradually from 14.5 to

5.4.

S : Space of beam (m);l : Span of beam (m).

3 Section modulus of the transverse girder of the top deck is not to be less than that obtained from the following

formula:

6.1 bl2 (cm3)

Where:

b: Distance between the mid-points of two adjacent spans of the beams supported by the girder (m)

l : Span of girder (m)

5.4.9 Safety deck

1 Scantlings of the safety deck as constructed as the tanks are to be in accordance with the requirements in5.4.3, 5.4.4 and5.4.5.

2 Scantling of the safety deck as constructed as other than the tanks are to be as follows:

(1) Thickness of the deck plates is not to be less than 6.5 mmor obtained from the following formula:

3.9 S h + 2.5 (m)

Where:

S : Beam space (m)

h : Deck loads (tons/m2)

(2) Section modulus of the deck beam is not to be less than obtained from the following formula.

4.2 Shl2 (cm3)Where :

S : Beam space (m)

h : Deck loads (tons/m2)

l : Span of beam (m)

(3) Section modulus of the deck ginders is not to be less than that obtained from the fol lowing formula.

4.75 bhl2 (cm3)

Where:

b: Distance between the mid-points of two adjacent spans of the beams supported by the girders (m)

l : Span of the girder (m);

h: deck load (tons/m2

)

5.4.10 Non-water tight str uctures

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t c v n 6274 : 2003, Chapter 5

The thickness of the web plates of the non-water tight structures such as the center girder, side girders and

solid floors of the pontoon, and the non-water tight bulkheads, is not to be less than obtained from the

following formula in general:

10 S1 (mm)

Where:

S1 : Space of stiffeners (m).

5.4.11 Keel block and supporting str uctur e

The keel blocks and their supporting structures are to be generally designed to the following loads :

P= 1.5 Q/L (tons/m)

Where:

P: Loads to the keel blocks and their supporting structures over the whole length of the dock.

Q: The maximum lifting capacity of the dock (tons)

5.4.12 Platforms

The minimum load on the platforms of dock ends is to be 600 kg/m2, the factor of safety is not to be less than

4.

5.4.13 Swing br idge

The minimum load on the swing bridge at dock ends is to be 400 kg/m2, the factor of safety is not to be less

than 4.

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t c v n 6274 : 2003, Chapter 6Cha pt er 6 MACHINERY AND INSTRUMENTATION

6.1 Machinery

6.1.1 Machinery

The pressure vessels other than those belonging to Group 3 and essential machinery such as machinery drivinggenerator and auxiliary machinery which are necessary for operations of the docks, are generally to be in

accordance with the relevant provisions of the Ship Rules.

6.1.2 Piping system

1 The piping systems are generally to be in accordance with the relevant provisions of the Ships Rules as far as

applicable.

2 The dock is to have at least two water ballast pumps. The arrangements for de-ballasting are to be such that in

case of failure to the one pump an alternative pump is available for each ballast tank.

6.1.3 Electr ical equipment

1 Electrical equipment are to be installed in the manner of minimizing the risks due to electrical cause such as

electric shocks, fi res etc. in accordance wi th the requirements of Part 4 of "Ship Rules".

2 Electrical machinery and cables are to be those conformed to an applicable standards accepted by VR, and

suitable to be used safely and effectively under the conditions of the environment where they are installed.

3 Electric circuits are to be protected against accidental overcurrents including short circuit, These protecting

devices are to be capable of breaking a fault circuit, eliminating the expansion of the faults and the hazards of

fire and securing to serve electric power to essential driving sources, lights, internal communications and

alarm devices.

6.2 Indicator system

Deflection metres or acceptable alternatives, tank level, draught, and trim indicators are to be provided to

enable the operation of the dock to be properly controlled.

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t c v n 6274 : 2003, Chapter 7

Cha pt er 7 FIRE PROTECTION AND EXTINGUISHING

7.1 General

The requirements of this Chapter apply to the minimum fire protection and extinction for the docks and do not

cover equipment fitted for fighting fires that may occur on ships in the dock. Attention should also be given to

any relevant statutory requirements of the National Authority of the country in which the dock is to operate.Compliance with such statutory requirements may, at the discretion of VR, be accepted as meeting the

requirements of this Chapter.

7.2 Fire protection

7.2.1 Accommodation

Accommodation, control station and service spaces are to be arranged so that the risk of fire will be reduced to

a minimum. Deck houses are to be of steel or equivalent materials. Deck coverings on the decks forming the

crown of machinery spaces are to be of a type which will not readily ignite.

7.2.2 Machinery space

Boundary walls of the machinery spaces and interior stairways below the top deck are to be of steel or

equivalent materials.

7.2.3 Paints

In accommodation, control station, service and machinery spaces, etc paints, varnished and similar

preparations having a nitrocellulose or other highly inflamable bases are not to be used.

7.3 Fire-extinguishing

7.3.1 Fire system

The fire pumps, associated piping and fire main are to be so designed that a minimum pressure can be

maintained sufficient to produce at least 12 m jet throw through adjacent nozzles of sizes required by 7.3.2. A

fire main is to be provided on each dock wing. Two separate means of water supply are to be provided for the

fire main. At least, one mean of water supply is to be of an adequate shoreside supply or an independent

driven emergency pump is to be provided with the dock.

7.3.2 Hydr ant, hose and nozzle

1 The number and position of the hydrants are to be such that at least two jets of water not emanating from the

same hydrant, one of which is to be from a single length of hose, may reach any part of the dock except the

water ballast tanks under any operating conditions.

2 In spaces containing machinery with a total power of 1,000 PH and over, two hydrants are to be provided, and

in spaces containing machinery with the total power less than 1,000 PH one hydrant will be accepted. Where,

in either of the above cases, fire fighting from within a small compartment is impracticable due to limitations

in space, the hydrants required may be situated outside and adjacent to the compartment entrance.

3 The fire hoses are to be sufficient in length to protect a jet of water to any of the spaces in which they may be

required to be used. The hoses are not to exceed 18 metresin length with a nozzle in size of 12 mmor over.

7.3.3 International Shore Connection

It is recommended that the top deck of the dock is provided with the international shore connection specifiedin Chapter 22, Part 5 of the Ship Rules to supply water to the docking ship s extinguisher f rom the docks

pump.

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t c v n 6274 : 2003, Chapter 77.3.4 Portable extinguisher

1 Portable extinguishers are to be placed onboard in places with risk of fire. Within the accommodation portable

extinguishers are to be so placed that at least one extinguisher will be accessible from any part of the

accommodation. The total number of extinguishers required within the accommodation area will depend on its

size and arrangement.

2 Portable extinguishers are to be provided in machinery spaces as well as spaces with electric motors andswitchboards etc. for pumps, warping capastans etc. Number and location will depend on the size and

arrangement of the spaces.

7.3.5 Fire smothering gas system

Where provision is made for the injection of gas into machinery spaces for fire-extinguishing purposes, the

necessary pipes for conveying the gas are to be provided with control valves or cocks which are to be so

placed that they will be easily accessible and not readily cut off from use by an outbreak of fire. Suitable

provision is to be made to prevent inadvertent admission of the gas to any compartment.