SJ-5112 Perancangan Geometrik Jalan

Element of Design

Sony Sulaksono Wibowo, Ph.D

Element of Design

o Sight Distance

o Horizontal Alignment

o Vertical Alignment

o Cross Section

Vertical AlignmentVertical Alignment

http://www.scvresources.com/highways/sr_23.htmhttp://www.scvresources.com/highways/sr_23.htm

Vertical Alignment

o Objective:

� Determine elevation to ensure

� Proper drainage

� Acceptable level of safety

o Primary challenge

� Transition between two grades

� Vertical curves

Vertical Curve Fundamentals

o Vertical curve � Parabolic function

� Constant rate of change of slope

� Implies equal curve tangents

o y is the roadway elevation x stations (or feet) from the beginning of the curve

cbxaxy ++= 2

Types of Verticals Curves

Vertical Curve Fundamentals

Notes:G1, G2 in percent; L in meters

Vertical Curve Fundamentals… continued

K is the number of horizontal meter needed for a 1% change in slope(panjang lengkung vertikal tiap perubahan 1% nilai A)

AKLA

LK ⋅=⇒=

Other properties of vertical curve:

Crest Vertical Curves - SSD

G1G2

PVI

PVTPVC

h2h1

L

SSD

( )

( )2

21

2

22100 hh

SSDAL

+= ( )

( )A

hhSSDL

2

21200

2+

−=

For SSD < L For SSD > L

Line of Sight

Crest Vertical Curves - SPD

G1

G2

PVI

PVTPVC

h2h1

L

SPD

( )

( )2

21

2

22100 hh

SPDAL

+= ( )

( )A

hhSPDL

2

21200

2+

−=

For SPD < L For SPD > L

Line of Sight

Crest Vertical Curves

o Assumptions for design

� h1 = driver’s eye height = 1,080 mm

� h2 = tail/head light or object height = 600 mm

o Simplified Equations

( )658

2

SAL = ( )

ASL

6582 −=

For S < L For S > L

2158

2S

K = S could be SSD or SPD

Design Controls for Crest Vertical Curves

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Design Controls for Crest Vertical Curves

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Sag Vertical Curves

G1 G2

PVI

PVTPVC

h2=0h1

L

Light Beam Distance (SSD)

( )( )βtan200

1

2

Sh

SSDAL

+= ( ) ( )( )

A

SSDhSSDL

βtan2002

1+

−=

For SSD < L For SSD > L

headlight beam (diverging from LOS by β degrees)

Sag Vertical Curves

o Assumptions for design

� h1 = headlight height = 600 mm

� β = 1°

o Note:

� Effect on passenger comfort of the change in vertical direction is greater

on sag than on crest vertical

� Gravitational and centripetal forces are in

opposite directions

Design Controls for Sag Vertical Curves

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Design Controls for Sag Vertical Curves

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Sight Distance at Undercrossing

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

S > L

S > L

Case of truck: h1 = 2.4 m

S > L

S < L

C = 5 meter (PP No. 34 tahun 2006)

An Issue on Alignments CombinationHorizontal and Vertical Alignment

Alignment Coordination

o Curvature and grade should be in proper balance

o It should avoid:

� Excessive curvature to achieve flat grades

� Excessive grades to achieve flat curvature

o Vertical curvature should be coordinated with horizontal

o Sharp horizontal curvature should not be introduced at or near the top of a pronounced crest vertical curve

o Drivers may not perceive change in horizontal alignment, especially at night

Alignment Coordination

o Sharp horizontal curvature – not at bottom of steep grade

o Not near low point of sag vertical curve

� Horizontal curves appear distorted

� Vehicle speeds (especially trucks) are highest at the bottom of a sag vertical curve

� Can result in erratic motion

Alignment Coordination

o On two-lane roads when passing is allowed, need to consider provision of passing lanes

� Difficult to accommodate with certain arrangements of horizontal and vertical curvature

� need long tangent sections to assure sufficient passing sight distance

Alignment Coordination

o At intersections where sight distance needs to be accommodated, both horizontal and vertical curves should be as flat as practical

o In residential areas, alignment should minimize nuisance to neighborhood

� Depressed highways are less visible

� Depressed highways produce less noise

� Horizontal alignments can increase the buffer zone between roadway and cluster of homes

Alignment Coordination

o When possible alignment should enhance scenic views of the natural and manmade environment

� Highway should lead into not away from outstanding views

� Fall towards features of interest at low elevation

� Rise towards features best seen from below or in silhouette against the sky

Alignment Coordination

o Coordination of horizontal and vertical alignment should begin with preliminary design

o Easier to make adjustments at this stage

o Designer should study long, continuous stretches of highway in both plan and profile and visualize the whole in three dimensions

Alignment Coordination

o Should be consistent with the topography

o Preserve developed properties along the road

o Incorporate community values

o Follow natural contours of the land

Alignment Coordination

o Does not affect aesthetic, scenic, historic, and cultural resources along the way

o Enhances attractive scenic views

� Rivers

� Rock formations

� Parks

� Historic sites

� Outstanding buildings

Alignment Coordination

Alignment Coordination

Visual Effect in

Combination of Horizontal and Vertical Curves

Visual Effect inCombination of Horizontal and Vertical Curves

Visual Effect inCombination of Horizontal and Vertical Curves

Visual Effect inCombination of Horizontal and Vertical Curves

Visual Effect inCombination of Horizontal and Vertical Curves

Alignment and Profile Relationships in Roadway Design

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Alignment and Profile Relationships in Roadway Design

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Alignment and Profile Relationships in Roadway Designfrom AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

Alignment and Profile Relationships in Roadway Design

from AASHTO’s A Policy on Geometric Design of Highways and Streets 2001

PROV INSI NADKP2T JALAN/JEMBATAN

HORIZONTAL = 1 : 1000

VERTIKAL = 1 : 100

STA

AN

TO

DA

DA

NG

13NAD2006

STA. 3+403,35 - 4+000

PENAMPANG MEMANJANG JALAN (SEKSI 02)

LEM BAR NOJML LEM BARPROVINSIK P / THNPROYEK

NO

MO

R

ME

MA

NJA

NG

NO

TA

SI

BA

NG

UN

AN

DIP

ER

IKS

A

PA

TO

K-P

AT

OK

DIP

ER

IKS

A

KE

MIR

ING

AN

DIP

ER

IKS

A

DIG

AM

BA

RB

UK

U U

KU

R

DIU

KU

R

PO

TO

NG

AN

T

AN

GG

AL

OL

EH

PE

KE

RJA

AN

120

PI 1

PI 2

PI 3PI 4

PVI 1

PVI 2PVI 3

PVI 4

3+403,35

9,052 9,052W

2,263 2,263

6 (-)

6 (+)TC CT

- 2 %0 %

6,7896,789

7,784

41,909 41,909W

10,477 10,477

6 (-)

6 (+)TC CT

- 2 %0 %

31,43231,432

34,782

53,633 53,633W

10,477 10,477

6 (-)

6 (+)TC CT

- 2 %0 %

31,43231,432

30,206

21,458 21,458W

5,364 5,364

6 (-)

6 (+)TC CT

- 2 %0 %

16,09316,093

12,122

BRG

MAKAM ISLAM

3+403.3

5

3+500

3+550

3+

600

3+650

3+700

3+750

3+80

0

3+

85

0

3+900 3+950 4+

000

3+350

3+400

3+

403.3

53+350

3+400

3+

403.3

5

PC

= 3

+5

00.6

6P

T =

3+

516.2

0 PC

= 3

+564.6

5

PT

= 3

+6

31.6

0

PC = 3+775.54

PT

= 3

+8

27

.28

PC

= 3

+8

46

.51

PT

= 3

+8

70

.63

2

4

6

8

10

12

14

16

18

20

22

24

3+500 3+600 3+700 3+800 3+900 4+000

10

.28

6

10

.44

4

10

.23

3

9.7

88

9.3

82

9.1

53

9.0

62

9.3

33

9.5

42

9.4

95

9.4

05

9.0

44

9.0

00

9.0

00

7 0 . 00 0 0 m VC

BV

CS

: 3

+4

25

BV

CE

: 1

0.3

53

EV

CS

: 3

+4

95

EV

CE

: 1

0.2

37

10

.38

8

5 0 .0 0 0 0 m VC

BV

CS

: 3

+6

56

.50

BV

CE

: 9

.20

5

EV

CS

: 3

+7

06

.50

EV

CE

: 9

.16

5

9.1

39

10

.20

5

9.8

86

9.5

66

9.2

47

5 0 .0 0 00 m VC

BV

CS

: 3

+7

64.3

9

BV

CE

: 9

.44

2

EV

CS

: 3

+8

14

.39

EV

CE

: 9

.501

9.5

21

9.3

74

6 0. 0 0 00 m VC

BV

CS

: 3

+9

90

BV

CE

: 9.0

73

EV

CS

: 4

+05

0

EV

CE

: 8

.99

9

9.0

51

8.9

99

9.4

14

9.2

93

9.1

71

8.9

99

end of this part