rockfield technologies australia pty. ltd.as4084-2012 technical letter: pallet racking system...

Rockfield Technologies Australia Pty. Ltd. (ABN 53092464376) 155 Hugh street, Currajong Q 4812, Townsville. Australia

Telephone: +61> 07 47255874, Facsimile: +61> 07 47 255879

TECHNICAL REPORT

STEEL STORAGE RACKING SYSTEM

TESTING TO AS4084-2012

FOR

NANJING JIANGRUI STORAGE EQUIPMENT CO., LTD.

February 2014

Rockfield Technologies

Australia Pty. Ltd.

Document No. PM012013.M7 Revision Final Issue date 4th February 2014 Page II

Rockfield Technologies Australia Pty Ltd COMMERCIAL-IN-CONFIDENCE

Pallet Racking System Testing to AS4084-2012

Technical Letter: Pallet Racking System Testing to AS4084-2012

Date: 4th February 2014

Distribution: Nanjing Jiangrui Storage Equipment Co., Ltd.

Limitation Statement The sole purpose of this technical report and the services performed by Rockfield Technologies Australia Pty Ltd (Rockfield) was to conduct physical testing and beam element analysis to assess manufacturer design load ratings for selected Nanjing Jiangrui Storage Equipment Co., Ltd. (J-Rack) pallet storage racking systems, based on test methods outlined in AS4084:2012 – Steel Storage Racking. The findings and results are based on the physical testing of a limited number of samples/specimens provided by J-Rack. No warranty, or guarantee, whether expressed or implied, is made with respect to data not directly measured during this investigation, or to the observations and conclusions expressed as a result of that data. The load capacities have been developed based on experimental testing of supplied components. J-Rack should ensure that the material strength of their racking components meet or exceeds those used for design for the tables to be applicable. The report has been prepared on behalf of and for the exclusive use of J-Rack. J-Rack may share the final report and/or details included with their distributors; however the data, results and outcomes listed are proprietary to J-Rack only. Rockfield accepts no liability or responsibility whatsoever for or in respect of any use or reliance upon this report by any third party.

Report Number PM012013.M7

Revision Final

Date 4th February 2014

Name Date Signature

Prepared by: Jodish Thomas 04/02/2014

Reviewed by: Daniel Stephenson 04/02/2014

Approved by: Govinda Pandey 04/02/2014

Rockfield Technologies Australia Pty Ltd 155 Hugh Street, Currajong QLD,4812 PO Box 25 Thuringowa Central Qld 4817 Tel: +61 (0)7 4725 5874, Fax: +61 (0)7 4725 5879 Email: [email protected] Website: www.rockfieldtechnologies.com

Document No. PM012013.M7 Revision Final Issue date 4th February 2014 Page III



Contents

Contents............................................................................................................................... III

1. Preamble ....................................................................................................................... 1

2. Introduction .................................................................................................................. 1

3. Experimental Apparatus & Measurement Setup ........................................................ 2

4. Physical Testing ........................................................................................................... 3

4.1 Test on Uprights ...................................................................................................................... 5

4.1.1 Stub Test ............................................................................................................................ 5 4.1.2 Compression Test ............................................................................................................ 6 4.1.3 Bending Test on Upright Sections .................................................................................. 8

4.2 Pallet Beam Tests .................................................................................................................10

4.2.1 Bending Test on Beams .................................................................................................10 4.3 Pallet Beam to Upright Connection Tests .............................................................................13

4.3.1 Cantilever Test ................................................................................................................13 4.3.2 Shear Test on Beam End Connector ............................................................................15 4.3.3 Shear Test on Beam End Connector Locks .................................................................16 4.3.4 Looseness Test on Beam/Upright Connection ............................................................17

4.4 Upright Frame Tests .............................................................................................................18

4.4.1 Test for Shear Stiffness of Upright Frames .................................................................18 4.5 Test on Floor Connections ....................................................................................................20

5. Global Structural Analysis ......................................................................................... 22

5.1 Beam Element Modelling ......................................................................................................23

5.2 Load Cases ...........................................................................................................................24

5.3 Load Capacity Tables ...........................................................................................................26

6. Conclusions & Recommendations ............................................................................ 31

References .......................................................................................................................... 31

Appendix A: Test Apparatus General Assembly Drawings ............................................. 32

Appendix B: Coupon Test Results .................................................................................... 36

Appendix C: Material Specifications from J-Rack ........................................................... 38

Appendix D: Manufacturer Design Data ........................................................................... 39

Appendix E: Pallet Racking Component Drawings .......................................................... 40

Document No. PM012013.M7 Revision Final Issue date 04th February 2014 Page 1



1. Preamble

Nanjing Jiangrui Storage Equipment Co. Ltd. (J-Rack) design and manufacture steel storage racking

systems and are based in China. A typical selective pallet racking system comprises braced upright

frames spanned (connected) by pallet beams.

Rockfield were contacted by J-Rack to assist with compliance with regulatory documents (such as

relevant International and Australian design standards) concerning their pallet racking system.

Rockfield have performed physical testing and analysis on selected items from the racking system to

ensure compliance in accordance with the Australian Standard AS4084 2012 - Steel Storage Racking

[1].

2. Introduction

The Australian Standard [1] covers the minimum requirements for the fabrication and erection,

physical testing, operation, maintenance and design of steel storage racking using limit state methods.

According to Section 3 [1], the pallet racking system shall be designed as follows:

1. A global analysis of the structure shall be made in order to determine the distribution of

design actions (such as internal forces, moments or stresses) and displacements, as

specified in Clause 3.3 [1].

2. Individual elements of the structure and connections shall be checked to ensure that the

elements have adequate resistance in the ultimate limit state, and that unacceptable

deformations do not develop in the serviceability limit state, as specified in Section 4 [1].

According to Section 4.1 [1], in cases where adequate methods of design calculations are not

available, physical testing shall be performed to measure the adequate resistance of pallet racking

components in the ultimate limit state.

Rockfield have been engaged to conduct physical testing of various components/configurations to

determine capacities and parameters critical to the design of steel storage racking. Additionally, the

scope of work covers development of generic pallet beam and upright frame load capacity tables.




3. Experimental Apparatus & Measurement Setup

Purpose-built test apparatus frames were utilised for the physical testing. The test rigs were designed

to facilitate a range of tests on upright frame sections, beams, upright-beam connections and base

plates, in accordance with Section 7 [1]. General assembly drawings of the test apparatus are given in

Appendix A. Figure 3.1 shows an example of the apparatus setup for the pallet beam test.

Instrumentation for the apparatus included:

10 and 30 tonne capacity hydraulic cylinders for load application;

Calibrated 10 and 50 tonne range load cells for measuring applied force;

Linear voltage displacement transducers (LVDTs) for measuring deflections at various

locations of the test specimens as specified in Section 7 [1];

Inclinometer for measuring angular rotations; and,

A data logger to record concurrent measurement results at a frequency of 1Hz.

Figure 3.1 Test apparatus configured for major axis beam bending test




4. Physical Testing

The following tests were conducted to find the stiffness and/or load/moment capacities of various

members, their connections and base plates in accordance with Section 7 [1].

1. Test on uprights.................................................................................................... Section 7.3

a) Stub column test........................................................................................... Section 7.3.1

b) Compression test on uprights....................................................................... Section 7.3.2

c) Bending test on upright sections, in both major and minor axes................. Section 7.3.4

2. Pallet beam tests................................................................................................... Section 7.4

a) Bending test on beams, in both major and minor axes................................ Section 7.4.2

3. Pallet beam to upright connection tests................................................................. Section 7.5

a) Cantilever tests............................................................................................. Section 7.5.1

b) Shear test on beam end connectors............................................................. Section 7.5.2

c) Shear test on beam end connector locks..................................................... Section 7.5.4

4. Upright frame test.................................................................................................. Section 7.7

a) Test for shear stiffness of upright frames..................................................... Section 7.7.1

6. Test on floor connections....................................................................................... Section 7.9

The testing incorporated the more commonly used pallet racking components. The components

chosen for testing were as follows:

1) Upright frame:

a) Upright section (Type A): 90 x 67 x 1.8 mm thick

b) Cross bracing member: 37 x 24 x 1.5 mm thick

2) Beam and upright connector (including lock):

Beam Span

Beam Section Size (1.5 mm wall thickness)/Number of Connector Hooks

80x50/3 100x50/4 110x50/4 120x50/4 140x50/4 160x50/4

1372 x 1829 x 2591 x x x x x x 2743 x x x x x x 3048 x x x x 3658 x x x 3810 x x x

Connector Lock: 73 x 30 x 0.5 mm thick

3) Floor connection:

a) Conventional base plate: 155 x 130 x 5.0 mm

Coupon tests on uprights and beams were conducted to measure the base metal thickness and yield

and ultimate strength of the test specimens. This test was performed in accordance with AS1391 [3].

The coupon test results were used in correction formulae for physical testing results in accordance

with AS4084 [1]. The results are shown in Table 4.0.1, Table 4.0.2 and Appendix B.




Table 4.0.1 Material properties & test results - Beam

Nominal Yield Strength, fy

(MPa)

Nominal Thickness, t

(mm) Test

Number

Tested Yield Strength, ft

(MPa)

Tested Tensile

Strength, fu (MPa)

Measured Thickness, t

(mm)

270 1.5 1 255 389 1.45 2 260 399 1.45 3 295 383 1.44

Average 270 390 1.45

Table 4.0.2 Material properties & test results - Upright

Nominal Yield Strength, fy

(MPa)

Nominal Thickness, t

(mm) Test

Number

Tested Yield Strength, ft

(MPa)

Tested Tensile

Strength, fu (MPa)

Measured Thickness, t

(mm)

365 1.8 1 345 397 1.75 2 320 390 1.75 3 345 398 1.76

Average 337 395 1.75 Note that there is a significant difference between the nominal yield strength of the typically supplied

beam material and the material strength specified in the manufacturer’s product quality certificates. It

is feasible that greater beam and frame capacities would be achievable with samples supplied with

greater material strength. However this report makes no allowance for increased load capacities as a

result of possibly higher material strengths.




4.1 Test on Uprights

4.1.1 Stub Test

In accordance with [1], the form factor, Q, of the upright sections was determined by stub tests as

specified in [2].

Test Procedure & Results:

Tests were carried out on six (6) 305 mm long upright sections in accordance with Clause 8.1.2 [2].

The results are shown in Table 4.1.1 and Figure 4.1.1 shows the test pieces. The form factor, Q, was

calculated in accordance with Clause 7.3.1.2 [1].

Table 4.1.1 Stub column test results

Upright 90x67x1.8

Cross Sectional Area (mm

2)

Test Number

Axial Failure Load (kN)

Gross 458 1 129.6 Min 418 2 132.5

3 135.8 5 137.2 6 132.7 Form Factor, Q 0.95

Note: One (1) test was omitted due to poor alignment during testing.

Figure 4.1.1 Stub test specimens




4.1.2 Compression Test

The purpose of this test was to determine the axial load capacity of the upright section for a range of

effective lengths, taking into account out of plane buckling effects and torsional restraint provided by

bracing and its connections to the uprights. Figure 4.1.2 shows an example of a typical compression

test setup.

Figure 4.1.2 Upright Compression Test Setup





The testing procedure adopted was in accordance with Clause 7.3.2 [1]. Tests were carried out on

upright sections of various lengths. The lengths chosen for the test were based on Clause 7.3.2.3 [1].

The shortest length corresponds to single brace spacing and the longest corresponds to a

slenderness ratio of 2.0 in down-aisle buckling. Three tests were conducted on each length of upright

frame. The average compressive strength/axial load capacity of the upright sections are given in

Table 4.1.2

Table 4.1.2 Upright frame compression test results

Upright section length (mm)

Testing average axial load capacity (kN)

Mean slenderness

ratio ()

Characteristic

stress reduction factor ()

1067 84.9 0.398 0.531 2362 71.9 0.855 0.485 3356 66.2 1.256 0.379 4875 48.0 1.824 0.291 6096 30.8 2.281 0.173

Figure 4.1.3 graphs the characteristic stress reduction factor against slenderness ratio of the upright

sections in accordance with Clause 7.3.2.5 [1]. This graph is used in determining the load capacity

tables for the steel pallet racking storage upright frames.

Figure 4.1.3 Column Curve for Upright Frames

y = 0.0087x3 - 0.0649x2 - 0.0708x + 0.5723

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 1.10 1.20 1.30 1.40 1.50 1.60 1.70 1.80 1.90 2.00 2.10 2.20 2.30 2.40

(C

har

acte

rist

ic s

tres

s re

du

ctio

n fa

cto

r)

(Slenderness ratio)

Upright Compression Curve

Line of best fit




4.1.3 Bending Test on Upright Sections

The purpose of this test was to determine the bending capacity of the upright sections about the major

and minor axes. Figure 4.1.4 shows a typical major axis bending test setup.

Figure 4.1.4 Upright bending - major axis bending test


The testing procedures adopted for the upright frame bending test were in accordance with

Clause 7.3.4 [1]. The length of upright sections (90x67x1.8) varied from 1000 to 2500 mm depending

on the test. The test results are shown in Tables 4.1.3 and 4.1.4

Table 4.1.3 Major axis (X-X) bending test results for uprights

Test Number

Failure Bending Moment (kN.m)

1 3.28 2 3.35 3 3.27

ØMx 3.14 Note: The observed failure mode of the major axis bending of the upright frames was torsional

buckling, likely induced by the bracing arrangement. It is recommended that a larger/stronger spacer

be used at the horizontal brace ends to help control twisting during strong axis bending.




Table 4.1.4 Minor axis (Y-Y) positive (+) and negative (-) bending test results for uprights

Test Number


(+)


(-)

1 2.53 1.99 2 2.57 2.05 3 2.50 2.14 4 2.48 - 5 2.47 -

ØMy 2.41 1.80

The major and minor bending moment capacities of upright sections were calculated in accordance

with Clause 7.3.4.4 [1] and incorporated corrections and statistical influences (such as mean and

standard deviation) as specified in Section 7.2 [1].




4.2 Pallet Beam Tests

4.2.1 Bending Test on Beams

The purpose of this test was to measure the bending strength of a beam under the service action (unit

load). This is an essential test to find out the safe load carrying capacity per beam pair in a pallet

racking system. Figure 4.2.1 shows a typical pallet beam (major axis) bending setup.

Figure 4.2.1 Beam bending - major axis bending test





The testing procedures adopted for the pallet racking testing were in accordance with Clause 7.4.2 [1].

Three different types of beams were tested on both major and minor axes and the loading pattern

considered was in accordance with Figure 7.4.2.2 [1]. The major axis bending strength test results are

listed in Table 4.2.1. The major and minor axis beam bending capacities were found in accordance

with Clause 7.4.2.5 [1].

Table 4.2.1 Major axis (X-X) bending test results for beams

Beam Size Beam Span Corrected failure load

(kg per pair) Beam major axis bending capacity

ØMx (kN.m)

80x50

1372 3530 3.75 1829 2630 4.01 2591 3570 4.86 2743 3490 5.03

100x50 2591 4910 7.11

2743 4460 6.88

110x50

2591 4730 6.95

2743 4640 7.27

3048 3780 6.33

120x50

2591 5240 7.78

2743 5800 9.18

3048 4550 7.78

3658 3590 7.25

3810 2850 6.17

140x50

2591 6240 9.39

2743 5810 9.34

3048 5640 9.80

3658 4300 8.97

3810 3860 8.63

160x50

2591 6530 9.96

2743 6520 10.65

3048 5750 10.18

3658 4650 9.91

3810 4140 9.50




A typical pallet load versus deflection curve is shown in Figure 4.2.2.

Figure 4.2.2 Load versus deflection curves for the 140x50x1.5 - 2591 span beam

The minor axis bending strength test results are listed in Table 4.2.2

Table 4.2.2 Minor axis (Y-Y) bending test results for beams

Beam Size Corrected failure load

(kg) Beam minor axis bending capacity

ØMy (kN.m)

80x50 1540 2.65 100x50 1430 2.45 110x50 1420 2.44 120x50 1540 2.64

140x50 1470 2.53

160x50 1480 2.54

0

1000

2000

3000

4000

5000

6000

7000

0 5 10 15 20 25

Forc

e a

pp

lied

(kg

)

Avg Midspan Deflection (mm)

Load Vs Deflection

Test 1

Test 2

Test 3




4.3 Pallet Beam to Upright Connection Tests

4.3.1 Cantilever Test

The purpose of this test was to determine the moment capacity and stiffness of the beam to upright

frame connection. Figure 4.3.1 shows a typical cantilever connection test setup.

Figure 4.3.1 Cantilever connection test setup


The testing procedures adopted for the cantilever testing were in accordance with Clause 7.5.1[1]. The

connection bending capacity, ØMc, and stiffness, k, was found in accordance with Clause 7.5.1.5 [1].

The cantilever connection test results are listed in Table 4.3.1

Table 4.3.1 Connection cantilever test results

Beam Size Connection capacity

ØMc (kN.m) Connection stiffness

k (kN.m/rad)

80x50 0.67 37.0 100x50 0.95 40.5 110x50 0.98 42.5

120x50 0.98 46.5

140x50 1.10 53.5

160x50 1.22 68.5 *Note: The test results for the 80x50x1.5 beams were comparatively low. This has affected most of the

80x50 pallet beam and frame configuration capacities. Additional testing can be conducted which may

yield greater capacity for the 80x50 beams.




A typical connection moment versus rotation curve is plotted in Figure 4.3.2. A summary graph of the

cantilever connection results is shown in Figure 4.3.3.

Figure 4.3.2 Moment versus rotation curves for 120x50x1.5 beam to upright connection

Figure 4.3.3 Summary of cantilever connection results

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140 0.160

Corr

ecte

d M

omen

t (k

N.m

)

Rotation (rad)

Moment Vs Rotation

Test 1Test 2Test 3

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

80 90 100 110 120 130 140 150 160

k (k

N.m

/rad

)

fM

c (k

N.m

)

Beam Depth (mm)

Cantilever Connection Summary

Moment (L)

Stiffness (R)




4.3.2 Shear Test on Beam End Connector

The purpose of this test was to measure the shear strength of the beam to upright frame connection.

Figure 4.3.4 shows a typical shear connection test setup.

Figure 4.3.4 Shear connection test setup


The testing procedures adopted for the beam end connectors were in accordance with

Clause 7.5.4[1]. The shear strength of the beam end connectors, ØVc, was determined in accordance

with Clause 7.5.4.5[1] and Table 4.3.2 lists the results.

Table 4.3.2 Shear test on beam end connector test results

Test Number

Connection shear failure load (kN)

Connection type

3 hook connection (80x50)

4 hook connection (100, 110, 120, 140, 160 x50)

1 18.68 29.16 2 21.08 27.28 3 20.60 28.56 4 - 29.57 5 - 29.88 6 - 27.28

ØVc (kN) 14.26 23.55 *Note: It was found that the shear capacity of the beam to upright connection is independent of the

beam depth, but is proportional to the number of hooks. Hence capacities given are in terms of

number of hooks for each connection type.




4.3.3 Shear Test on Beam End Connector Locks

The purpose of this test was to measure the shear strength of the connector locks. The connector

locks are critical to ensuring pallet beams are not accidentally dislodged from the uprights by

accidental actions (e.g. fork-lifts). Figure 4.3.5 shows a typical connection lock test setup.

Figure 4.3.5 Connection lock test setup


The testing procedures adopted for the beam end connector locks were in accordance with

Clause 7.5.4[1]. The shear strength of the beam end connectors, ØVc,l, was determined in accordance

with Clause 7.5.4.4[1]. Table 4.11 gives the test results. Clause 2.4.2[1] requires the lock capacity be

greater than 5.0 kN.

Table 4.3.3 Shear test on beam end connector lock test results

Test Number

Connection lock failure load (kN)

Connection type

3 hook connection (80x50)

4 hook connection (100, 110, 120, 140, 160 x50)

1 9.27 10.38 2 9.47 9.99 3 9.14 9.75 4 - 10.62

ØVc,l (kN) 7.86 8.25




4.3.4 Looseness Test on Beam/Upright Connection

The purpose of this test was to measure the looseness of the beam to upright frame connection.

Figure 4.3.6 shows a typical connection looseness test setup.

Figure 4.3.6 Connection looseness test setup


The testing procedures adopted for the beam end connector looseness were in accordance with

Clause 7.5.3[1]. The looseness of the beam end connectors, Øl, was determined in accordance with

Clause 7.5.3.5[1] and Table 4.3.4 lists the results.

Table 4.3.4 Looseness test on beam end connector test results

Beam Size

Average connection looseness (rads)

Connection type

3 hook

4 hook

80x50 0.003 - 100x50 - 0.0014 110x50 - 0.0019 120x50 - 0.0015 140x50 - 0.0016 160x50 - 0.0013 Max, Øl 0.003 0.002

*Note: It was found that the looseness of the beam to upright connection is mostly dependent on the

number of hooks. Hence capacities given are in terms of number of hooks for each connection type.




4.4 Upright Frame Tests

4.4.1 Test for Shear Stiffness of Upright Frames

The purpose of this test was to determine the transverse shear stiffness per unit length of upright

frame. Figure 4.4.1 shows a typical shear stiffness test setup.

Figure 4.4.1 Shear stiffness test setup




Test Procedure & Results

The testing procedures adopted for the shear stiffness test on upright frames were in accordance with

Clause 7.7 [1]. Load versus displacement of the frame from the testing is shown in Figure 4.4.2.

Figure 4.4.2 Load versus deflection curves for shear stiffness of upright frames (2900 mm long)

The linear stiffness of the frame, kti, was calculated in accordance with Clause 7.7.1.3[1] and was

found to be 0.71 kN/mm. The transverse shear stiffness of the frame, St, was calculated in accordance

with Clause 7.7.1.5[1] and was found to be 195 kN/m.

y = 0.5173x

y = 0.8546x

y = 0.7469x

0

2

4

6

8

10

12

14

0 2 4 6 8 10 12 14 16 18 20

Load

(kN

)

Deflection (mm)

Load Vs Deflection

Test 1

Test 2

Test 3




4.5 Test on Floor Connections

The purpose of this test was to measure the moment-rotation characteristics of the connection

between the upright and floor for a range of axial loads up to the maximum design strength of the

upright, and to determine the bending capacity of the base plate. Figure 4.5.1 shows a floor

connection test setup

Figure 4.5.1 Floor connection test setup


The testing procedures adopted for the floor connections tests were in accordance with Clause 7.9[1].

Six tests were conducted with the axial load varying over the range 1/6F1 to 1F1 (where F1 =

7,500 kg). The moment rotation curves for the conventional base plates are graphed in Figure 4.5.2.




Figure 4.5.2 Moment versus rotation curves for conventional base plate floor connections

The stiffness, kb, and bending capacity of the floor connection, ØMb, were calculated in accordance

with Clause 7.9.5[1]. The test results are given in Table 4.5.1.

Table 4.5.1 Floor connection test results

Test Number

Base Plate Type

Heavy Duty

Axial Load (kg) Ultimate Bending Capacity

(kN.m) Stiffness kb (kN.m/rad)

#

1 1250 0.70 93 2 2500 * 917 3 3750 0.86 478 4 5000 1.10 240 5 6250 1.44 655 6 7500 1.75 175

*Note: Results for test number 2 are vastly inconsistent with the other results and have been

discarded.

#Note: The base plate stiffness results are highly variable. The stiffness used in design has been

calculated in accordance with Clause 3.3.4.3[1] as follows: kb = EI/h = 95 kN.m/rad.

0

0.5

1

1.5

2

2.5

3

0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 0.045 0.05

Ave

rage

Mo

me

nt

Ap

plie

d o

n B

ase

Pla

te (

kN.m

)

Average Rotation of Base Plate (rad)

Moment Vs Rotation Curve

Test1-0.16F1

Test2-0.33F1

Test3-0.5F1

Test4-0.66F1

Test5-0.83F1

Test6-1.0F1




5. Global Structural Analysis

Section 3 of AS4084-2012 [1] states that: global analysis of the structure shall be made in order to

determine the distribution of design actions (such as internal forces, moments or stresses) and

displacements of the pallet racking system. Individual elements of the structure and connections are

checked to ensure that the elements have adequate resistance in the ultimate limit state, and that

unacceptable deformations do not develop in the serviceability limit state.

According to Clause 3.3[1], a comprehensive analysis of a complete frame, or in long racking a

representative number of bays, in either the down-aisle or cross-aisle direction, shall be carried out

using one or a combination of the following methods of analysis, within the limitations of Clause 3.3.8:

(a) Linear analysis (LA).

(b) Linear buckling analysis (LBA).

(c) Geometric non-linear analysis (GNA).

(d) Geometric and material non-linear analysis with geometric imperfections (GMNIA), types GMNIAc

and GMNIAs for frames composed of compact and non-compact members, respectively.

Clause 3.3.8[1] states that the frame classification shall be based on the elastic critical action ratio

(N*/Ncr), where: N* = design value of the vertical action on the frame and Ncr = elastic critical value of

the vertical action for buckling in a sway mode.

The type of global structural analysis on pallet racking system in both cross-aisle and down-aisle

directions were chosen based on the following conditions [1]:

If N*/Ncr ≤ 0.1, a frame shall be classified as stiff, i.e. the frame response to in-plane horizontal

forces is sufficiently stiff for it to be acceptably accurate to neglect any additional internal

forces or moments arising from horizontal displacements of the nodes.

If 0.1 < N*/Ncr ≤ 0.3, an LA analysis may be used in which second order effects are

incorporated using moment amplification factors in accordance with Clause 3.3.9.

(c) If N*/Ncr > 0.3, a GNA or GMNIA analysis shall be required in which second order effects

are treated directly.

For design simplicity, an elastic critical ratio >0.3 (conservative) was considered for all beam/frame

configurations. GNA analysis was conducted using beam element modelling in Space Gass. Also, key

assumptions considered for the design are given as follows:

Tolerance grade: I (Table 1.7.1(a) [1])

Placement actions: Goods placed with manually operated mechanical equipment.

Accidental horizontal actions: Upright protectors are used to a height of 1m, thus these actions

are not considered.

Wind, earthquake, thermal and floor loading actions are not considered.




5.1 Beam Element Modelling

Figures 5.1.1 and 5.1.2 show the typical configuration of pallet racking system that has been analysed.

The dimensions have been adopted from drawings supplied by J-Rack.

Figure 5.1.1 Generic pallet racking arrangement considered for design

Figure 5.1.2 Pallet racking system as modelled for beam element analysis

The beam element model includes the mechanical properties and material specifications of the

components provided by J-Rack. These specifications are provided in Appendix C. Section properties

of beams, uprights and bracing were based on J-Rack component drawings, which are given in

Appendix D. The beam/upright and base plate connections are considered as semi rigid joints with

stiffness values adopted from appropriate test results.




5.2 Load Cases

Section 2[1] lists the combinations of permanent, variable or accidental actions for which the racking

system is designed. The combination load cases for the beam element analysis were based on

Clause 2.7[1]. Load cases were considered in both cross aisle and down-aisle directions.

The following lists the factored combination cases considered for the ultimate limit state design:

a) Considering most unfavourable variable action:

1.3 (Self weight) + 1.4 (Unit load) + 1.4 (Load due to imperfections)

b) Considering all unfavourable actions that may occur simultaneously:

1.3 (Self weight) + 1.26 (Unit load) + 1.26 (Placement actions) +

1.26 (Load due to imperfections)

c) Considering accidental actions:

1.0 (Self weight) + 1.0 (Unit load) + 1.0 (Accidental actions) + 1.0 (Load due to imperfections)

The following lists the combinations considered for the serviceability limit state:

d) Considering most unfavourable variable action:

1.0 (Self weight) + 1.0 (Unit load) + 1.0 (Load due to imperfections)

Considering the imposed actions from the above load cases, the critical load pattern (Figure 2.7.2.1-a

[1]) was used for checking against each of the following criteria:

a) Overall stability in the down-aisle and cross- aisle directions,

b) Combined bending and axial compression of uprights,

c) Beam deflections and mid-span bending moments,

d) Bending & shear in beam-upright connections, and

e) Bending in base plate connections.




Figure 5.2.1 shows an example of a typical bending moment diagram on uprights for a sample load

case.

Figure 5.2.1 Bending moment diagram (upright XX) for a sample load case




5.3 Load Capacity Tables

The load capacity tables consider the capacity of the racking system based on the testing and

modelling results, and the requirements of AS4084. Analysis of the upright frames requires

consideration of combined axial compression and bi-axial bending. Clause 4.2.2[1] states that the

design of uprights requires the use of interaction equations as specified in Clause 3.5 [2] & Clause

5.2.4[1].

The interaction equation is as follows:

(N*/ØNc) + (Mx*/ØMx) + (My*/ØMy) < 1

Where,

N* is the axial compression force at ultimate limit state,

ØNc is the capacity of the member in compression for a given effective length,

Mx* is the major axis bending moment for the considered load case,

My* is the minor axis bending moment for the considered load case,

ØMx is the major axis bending capacity, and

ØMy is the minor axis bending capacity.

ØNc has been calculated for various effective lengths (height of first beam) by using the slenderness

ratios and corresponding characteristic stress reduction factor from Figure 4.1.2. N* is then found by

equating the appropriate values in the above formula. The maximum bay load for a pair of upright

frames is determined by correlating N* to the beam element modelling analysis results. Note that the

bending capacity of the beam/upright and base plate connection must also be considered when

determining the maximum allowable frame loads. Frame imperfection forces generate bending

moments at the beam/upright connection due to long-aisle portal frame action and this typically

governs the bay load capacity at shorter effective upright lengths. Serviceability limits are also

considered (sway deflection < h/200).

The maximum uniformly distributed load per pair of beams has been calculated by considering the

semi-rigid support (rotational spring stiffness) at the beam/upright connection. The load capacity is

based on the maximum bending moment capacity of pallet beam members/connections and on

serviceability (mid-span deflection < L/180) requirements. Tables 5.3.1 to 5.3.3 list the load capacity

values based on the aforementioned considerations for the pallet racking systems tested. Figures

5.3.1 and 5.3.2 graph the frame capacity results for first beam height = 1.143 m. Figure 5.3.3 graphs

the beam capacity results.




Table 5.3.1 Pallet Racking System – Frame Load Capacity Table – Part 1

Note: Some bay load capacities may be limited by beam/column or base plate connection.

Capacities are only valid for frames incorporating upright protectors to a height of 1m above base level

Beam Span =

1372 x Size =

Beam Span =

1829 x Size =

Height of

First Beam

(mm) 80x50 80x50 80x50 100x50 110x50 120x50 140x50 160x50 80x50 100x50 110x50 120x50 140x50 160x50

1143 8400 8300 6100 8400 8400 8400 8400 8400 5500 8400 8400 8400 8400 8400

1219 8400 8300 6100 8371 8371 8371 8371 8371 5500 8358 8358 8358 8358 8355

1372 8322 8291 6100 8240 8240 8240 8240 8240 5500 8227 8227 8227 8227 8224

1600 8113 8083 6100 8033 8033 8033 8033 8033 5500 8020 8020 8020 8020 8017

1829 7889 7860 6100 7812 7812 7812 7812 7812 5500 7799 7799 7799 7799 7797

1981 7734 7706 6100 7658 7658 7658 7658 7658 5500 7646 7646 7646 7646 7643

2210 7490 7462 6100 7416 7416 7416 7416 7416 5500 7404 7404 7404 7404 7402

2362 7321 7295 6100 7250 7250 7250 7250 7250 5500 7238 7238 7238 7238 7235

2591 7058 7032 6100 6989 6989 6989 6989 6989 5500 6978 6978 6978 6978 6975

2819 6786 6761 6100 6719 6719 6719 6719 6719 5500 6708 6708 6708 6708 6706

2972 6598 6574 6100 6533 6533 6533 6533 6533 5500 6522 6522 6522 6522 6520

3200 6310 6286 6100 6248 6248 6248 6248 6248 5500 6237 6237 6237 6237 6235

3429 6011 5989 6098 5952 5952 5952 5952 5952 5500 5943 5943 5943 5943 5941

3581 5809 5788 5893 5752 5752 5752 5752 5752 5500 5743 5743 5743 5743 5741

Up

righ

t 9

0x6

7x1

.8

Conventional Base Plate

Max Bay Load (kg)

Beam Span = 2591 x Size = Beam Span = 2743 x Size =




Table 5.3.2 Pallet Racking System – Frame Load Capacity Table – Part 2

Note: Some bay load capacities may be limited by beam/column or base plate connection.

Capacities are only valid for frames incorporating upright protectors to a height of 1m above

base level.

Table 5.3.3 Pallet Racking System – Beam Load Capacity Table

Height of

First Beam

(mm) 110x50 120x50 140x50 160x50 120x50 140x50 160x50 120x50 140x50 160x50

1143 8300 8300 8300 8300 8300 8300 8300 8200 8300 8300

1219 8300 8300 8300 8300 8285 8285 8272 8200 8272 8272

1372 8196 8196 8196 8196 8155 8155 8142 8137 8142 8142

1600 7990 7990 7990 7990 7950 7950 7937 7933 7937 7937

1829 7770 7770 7770 7770 7732 7732 7719 7714 7719 7719

1981 7617 7617 7617 7617 7579 7579 7567 7562 7567 7567

2210 7376 7376 7376 7376 7340 7340 7328 7324 7328 7328

2362 7210 7210 7210 7210 7175 7175 7163 7159 7163 7163

2591 6951 6951 6951 6951 6917 6917 6906 6902 6906 6906

2819 6683 6683 6683 6683 6650 6650 6639 6635 6639 6639

2972 6498 6498 6498 6498 6466 6466 6455 6451 6455 6455

3200 6214 6214 6214 6214 6183 6183 6173 6170 6173 6173

3429 5920 5920 5920 5920 5891 5891 5882 5878 5882 5882

3581 5721 5721 5721 5721 5693 5693 5684 5680 5684 5684

Up

righ

t 9

0x6

7x1

.8

Max Bay Load (kg)

Conventional Base Plate

Beam Span = 3048 x Size =

Beam Span = 3658 x

Size =

Beam Span = 3810 x

Size =

Beam Depth 1372 1829 2591 2743 3048 3658 3810

80 2850 2375 1275 1150

100 2400 2175

110 2825 2600 2200

120 3125 2875 2375 1775 1600

140 3700 3500 3000 2125 1975

160 3900 3950 3425 2825 2600

Span

Maximum uniformly distributed load per pair of beams (kg)




Figure 5.3.1 Frame capacities versus beam span

Figure 5.3.2 Frame capacities versus beam depth

5000

5500

6000

6500

7000

7500

8000

8500

9000

1000 1500 2000 2500 3000 3500 4000

Fram

e (B

ay)

Cap

acit

y (k

g)

Beam Span (mm)

Frame Capacity vs Beam Span for Varying Depth

80x50

100x50

110x50

120x50

140x50

160x50

5000

5500

6000

6500

7000

7500

8000

8500

9000

80 90 100 110 120 130 140 150 160

Fram

e (B

ay)

Cap

acit

y (k

g)

Beam Depth (mm)

Frame Capacity vs Beam Depth for Varying Span

1372

1829

2591

2743

3048

3658

3810




Figure 5.3.3 Beam capacities versus beam depth

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

1200 1700 2200 2700 3200 3700

Max

imu

m lo

ad p

er

pai

r (k

g)

Beam span (mm)

Beam capacity vs Span for Varying Depth

80

100

110

120

140

160




6. Conclusions & Recommendations

Based on the outcomes of the testing, analysis and design, the following recommendations and

conclusions are made:

1. Variation between the yield strength of the tested material and the nominal material yield

strength can have a significant impact on the final member/connection capacities. For

example, the certificate of material strength indicated a yield of 365 MPa while the average

specimen tested strength was 270 MPa. AS4084 does not make allowance for increasing the

design strength when physical testing was performed on material of less strength. Future

testing should be conducted on material as close as possible to the specified yield strength.

2. A larger/stronger spacer (between brace and upright) should be used at the horizontal brace

ends to help control twisting during strong axis bending of the upright frames.

3. Bending capacity of the beam/upright connector appears to be limited by the end

plate/connector. Capacity of the connection can likely be increased by increasing the

thickness of this plate. Also, tear-out of the beam connector hooks through the upright slot

was observed. Tearing of the slots was also observed in the connection shear test. Further

consideration should be made to strengthening this area. Additional testing will also likely

increase the capacity. An increased beam/upright moment connection capacity may also

result in increased frame capacities.

4. The typical failure mode for bending in the pallet beams during the beam major axis bending

tests was ‘pop-up’ of the top flange. That is, the upper flange of one of the two c-sections that

form the beams separated and lifted under compression. It is recommended that the spot

welds that hold the beam seam together be spaced more closely.

References

1. AS4084 – 2012 Steel Storage Racking.

2. AS/NZS4600 – 2005 Cold Formed Steel Structures.

3. AS1391 – 2007 Metallic materials - Tensile testing at ambient temperature.




Appendix A: Test Apparatus General Assembly Drawings




Appendix B: Coupon Test Results




Appendix C: Material Specifications from J-Rack




Appendix D: Manufacturer Design Data

Figure D-1 J-Rack Frame load capacity table

Figure D-2 J-Rack Box Beam load capacity table

Style of Upright M 90*70*1.8

Load capacity (1st b eam height from ground 1.0m) tons/pic 14.4


Load capacity (1st b eam height from ground 1.8m) tons/pic 12





Nanjing Jiangrui Storage Equipment Co., Ltd

Materials: Q235B (SS400)

BEAMS,max.deflection 1/200 Load table for pallet racking AS 4084-1993 and FEM 10.2.02

1372 1829 2591 2743 3048 3658 3810

DPNB0348 80*50*1.5 4500 2989 1643 1466

DPNB0440 100*50*1.5 2416 2156

DPNB0441 110*50*1.5 2811 2508 2031

DPNB0442 120*50*1.5 3208 2862 2335 1603 1478

DPNB0444 140*50*1.5 4348 3880 3142 2182 2011

DPNB0446 160*50*1.5 4500 4500 4201 2917 2689

DPNB0446/1 160*50*1.8

DPNB0446/2 160*50*2.0

Capacity of Dexion Beam

loading/pair(kg) length Beam Length (mm)

dimensionBeam Code

C\C Beam




Appendix E: Pallet Racking Component Drawings

Figure E-1: Beam sections




Figure E-2: 2591 x 80 x 1.5 beam

Figure E-3: 2591 x 100 x 1.5 beam




Figure E-4: 2591 x 110 x 1.5 beam

Figure E-5: 2591 x 120 x 1.5 beam




Figure E-6: 2591 x 140 x 1.5 beam

Figure E-7: 2591 x 160 x 1.5 beam




Figure E-8: H-Brace




Figure E-9: D-Brace

Figure E-10: Upright section




Figure E-11: 90x67x1.8 Upright

Figure E-12: Conventional Base-plate




Figure E-13: Frame Assembly

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