vol. 21 no. 2 JUnE 2008 MICA (P) no. 239/05/2008STEEl nEWS & noTES

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The President’s Corner -------------------------------- pg 2New Members ------------------------------------------- pg 3Bolted Connections in Steel Structures: Bolt Tightening ----------------------------------------- pg 4Members’ Night 2008 --------------------------------- pg 7Recent Innovations in Safety during Steelwork in The UK ----------------------------------------------- pg 724th AGM ----------------------------------------------pg 11

Corporate Members’ Night 2008 -------------------pg 11New Guide on the use of Alternate Steel Materials for Construction- How does it affect your business? ------------------pg 1224th Annual Lecture & Dinner ---------------------pg 13Tubular Structures in the Avant-Gardeof Architecture -----------------------------------------pg 13New Products and Services --------------------------pg 14

ION ORCHARD PROJECT

photo courtesy of Yongnam Engineering and Construction Pte Ltd

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The President’s CornerDear fellow-members,The surge in construct ion volume, while gladly welcomed by all segments of the industry, has brought with it, two great challenges: sharp increases in construction costs and acute personnel shortage. In fact, escalating cost is now the most important concern in the industry. The steel sector is one of the

parties bearing the brunt of this trend. Members will have to tread carefully in their business dealings. Hopefully, all key players can come together to help find solutions to alleviate the situation.

The SSSS has, all along, focused on education and training. The current situation strongly validates our stance. With the wide-spread shortage of trained manpower, the SSSS Certification Courses for Structural Steel Supervisors and Steel Engineers have become invaluable. Now, jointly run with the BCA Academy, the courses have already churned out more than 400 qualified structural steel supervisors and engineers. If necessary, we will step up the training. Corporate members and companies engaged in the design and construction of steel structures should send their relevant staff to this course. Meanwhile, our council members have also been busy helping the industry to prepare for the switch to the Euro-codes for structural design, especially the parts relating to steel and steel-concrete composite designs.

Oh, don’t forget to join us on 2nd July 2008 at the Sentosa Golf Club for the annual golf tournament organised to raise funds for the SSSS-BCA Scholarship and to promote interaction amongst members and others in the industry. And a gentle reminder that the 24th Annual Lecture and Dinner is scheduled on 28 August 2008 at the Meritus Mandarin, Orchard Road. This year, Prof Dr. Mick Eekhout of the Delf University of Technology, will speak on “Tubular Structures as the Avant Garde of Architecture.” An architect who specialises in steel structures, Prof Eekhout will show that the sculptural design and free form of many projects would not have been possible without tubular hollow sections. Don’t miss this most interesting lecture.

Warmest Regards,

Tan Tian Chong

Published by : Singapore Structural Steel Society1-B Aliwal Street, Chenn Leonn BuildingTel: 6392 1381 Fax: 6392 5330avconsul@pacific.net.sg www.ssss.org.sg

Printer : Motion Printers & Publications Pte LtdBlk 3023 Ubi Road 3 #06-08 Singapore 408663 Tel: 6783 3493 Fax: 6846 1636 Email:123@motionprinters.com

Council Members 2008/2009PresidentMr Tan Tian Chong, Building & Construction Authority(Tel: 6325 5921 email: tan_tian_chong@bca.gov.sg)Immediate Past PresidentAssoc Prof Richard Liew, National University of Singapore(Tel: 6516 2154 email: cveljy@nus.edu.sg)First Vice-PresidentMr Ho Wan Boon, Yongnam Engineering & Construction Pte Ltd (Tel: 9637 9971 email: wbho@yongnam.com.sg)Second Vice-PresidentMr Bernard Chung, Corus South East Asia Pte Ltd(Tel: 6297 6678 email: Bernard.Chung@corusgroup.com)Honorary SecretaryMr M.S. Islam, Singapore Polytechnic(Tel: 6879 0464 email: sirajul@sp.edu.sg)Honorary TreasurerMr Anthony Tan, BlueScope Lysaght (Singapore) Pte Ltd(Tel: 6661 1215 email: Anthony.Tan@bluescopesteel.com)Honorary AdvisorsMr Lim Keng Kuok, CPG Consultants Pte Ltd(Tel: 6357 4608 email: lim.keng.kuok@cpgcorp.com.sg)Assoc Prof Richard Liew, National University of Singapore(Tel: 6516 2154 email: cveljy@nus.edu.sg)Council MembersAssoc Prof Ang Kok Keng, National University of Singapore(Tel: 6516 2570 email: cveangkk@nus.edu.sg)Mr Chia Wah Kam, ARUP Singapore Pte Ltd(Tel: 9851 2309 email: chia.wahkam@arup.com)Mr Chor How Choon, The 22nd Mettallurgical Construction Corporation (S) Pte Ltd(Tel: 9879 1398 email: chor_howchoon@yahoo.com.sg)Dr Ng Yiaw Heong, Petro Process System Pte Ltd(Tel: 6545 9968 Ext 500 email: ngyh@toepl.com.sgMr John Sanderson, William Hare (SEA) Pte Ltd(Tel: 9856 8036 email: sandersonj@sandersongroup.com)Ms Serena Yap, TY Lin International Pte Ltd(Tel: 6278 3383 email: serenayap@tylin.com.sg)

Editorial Board : Dr Ang Kok Keng Mr Bernard ChungMr M.S. Islam (Hon Editor) Mr Lauw Su Wee Dr Ng Yiaw Heong Mr Look Boon Gee

STEEL NEWS & NOTES welcomes contributions on any suitable topic relating to steel use and construction. Publication is at the discretion of the Editor. Views expressed are not necessarily those of the SSSS, the Editor or the Publisher. Although care has been taken to ensure that all information contained herein is accurate with relation to either matters of fact or accepted practice at the time of publication, the SSSS and the Editor assume no responsibility for any errors in or misinterpretation of such information or any loss or damage arising from or related to its use. No part of this publication may be reproduced without the permission of the SSSS.

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New Members

Associate Members

AS 056 Bustamam Koshni Parsons Brinckerhoff Pte Ltd 13th March 2008AS 057 Yeow Ee Seong Khean Seng Engineering Sdn Bhd 13th March 2008

Ordinary Members

OM 770 Eng Chua Qwik Built-Tech International Pte Ltd 14th Feb 2008OM 771 Tsang Pui Shen WHL 14th Feb 2008OM 772 Toh Chin Keong Worley Parsons Pte Ltd 13th March 2008OM 773 Sabaratnam Kuhanesan Penta-Ocean Construction Co Ltd 13th March 2008OM 774 Ramlal Prakash DE Consultants (S) Pte Ltd 13th March 2008OM 775 Ng Gek San PT Consultants 13th March 2008OM 776 Loh Lean Chooi Loh Consultants Pte Ltd 13th March 2008OM 777 Puah Bee Kiat Kay Lim Construction & Trading Pte Ltd 13th March 2008OM 778 Kenny Foo Fonda Construction Pte Ltd 13th March 2008OM 779 Chew Wee Kong NYC System Engineering Pte Ltd 10th April 2008OM 780 Kumaravel Udayasurian Parsons Brinckerhoff Pte Ltd 10th April 2008OM 781 Ye Htut Thein Singapore Piling & Civil Engineering Pte Ltd 10th April 2008OM 782 Piyasanka KRM Worley Parsons Pte Ltd 10th April 2008OM 783 Lee Eng Ann Maunsell Consultants (S) Pte Ltd 10th April 2008OM 784 Tan Kian Wei Poh Lian Construction Pte Ltd 8th May 2008OM 785 Voon Kim Loon Poh Lian Construction Pte Ltd 8th May 2008OM 786 Chen Zhiwei Poh Lian Construction Pte Ltd 8th May 2008OM 787 Ang Bee Soon Poh Lian Construction Pte Ltd 8th May 2008OM 788 Ng Soi Nam Worldtex Engineering (S) Pte Ltd 8th May 2008OM 789 Chan Nget Loong SCE Consultants Pte Ltd 8th May 2008OM 790 Ho See Ling RSP Architects Planners & Engineers 8th May 2008OM 791 Wong Yew Fai CMP Consultants Pte Ltd 8th May 2008OM 792 Tang Weng Yew Maunsell Consultants (S) Pte Ltd 12th June 2008OM 793 Chan Yew Tong ARUP Singapore Pte Ltd 12th June 2008OM 794 Aaron Chia Surbana International Consultants Pte Ltd 12th June 2008OM 795 Chen Bo Worley Parsons Pte Ltd 12th June 2008OM 796 Soo Yet Chung Maunsell Consultants (S) Pte Ltd 12th June 2008OM 797 Liu Rui Qiang The 22nd Metallurgical Construction Corporation (S) Pte Ltd 12th June 2008OM 798 He Ze Feng The 22nd Metallurgical Construction Corporation (S) Pte Ltd 12th June 2008OM 799 Subramaniyam Arasaratnam Shimizu Corporation 12th June 2008

Corporate Members

CM 108 LBG-NGT Corporation Pte Ltd 10th January 2008CM 109 Zingametall (S) Pte Ltd 13th March 2008CM 110 ACL Construction (S) Pte Ltd May 2008CM 111 Shanghai Tonglei Construction Steel Product Co Ltd 8th May 2008CM 112 Hempel Asia Pacific 8th May 2008CM 113 Prelim Construction Pte Ltd 8th May 2008CM 114 Seng Leong Project Pte Ltd 12th June 2008

Bolted Connection in Steel Structures: Bolt Tightening

Ng Yiaw-Heong B.Eng.(Hons), MEng, PhD.

1.0 Introduction

Bolt tightening can be categorised into either “Snug-Tightened” or “Fully Tensioned”. Sometimes bolts may need to be fully tensioned, while sometimes snug tightening is sufficient. This always brings confusion at construction site and it is necessary for the design engineer to specify clearly what level of tensioning or snug is required in each bolted connection. In situations where the designer did not specify the bolt design philosophy, it is essential to seek clarification so that bolts can be properly tightened at site.

2.0 Design Philosophy

There are 3 fundamental modes of force transfer in bolted connections:i) Shear/Bearing Mode where forces are perpendicular to the bolt axis and transfer shear by bearing on the bolt and the

connected plies.ii) Friction Mode where forces are perpendicular to the bolt axis and transfer shear by frictional resistance of the contacting

surface.iii) Axial Tension Mode where forces to be transferred are parallel to the bolt axis.

BS 5950-1:2000 Section 6 classified usage of bolts to 2 types, non-preloaded bolts (clause 6.3) and preloaded bolts (clause 6.4). There are several reasons to adopt preloading in the bolt and one of the reasons to adopt preloading in the bolt is to prevent occurrence of slip for structure that are critical in deflection; eg. cantilever beam. The preloaded bolt is necessary if Friction Mode is required. The design procedure for preloaded bolts could be found in the code, clause 6.4. The code named the preloaded bolts as HSFG bolts.

3.0 Usage of Bolt

Standards that described the usage of bolts are as follows:-i) BS 4395 Part 1:1969 - Specification for High Strength Friction Grip Bolts and Associated Nuts and Washers for Structural

Engineering. Metric Series. General Gradeii) BS 4395 Part 2:1969 - Specification for High Strength Friction Grip Bolts and Associated Nuts and Washers for Structural

Engineering. Metric Series. Higher Grade bolts and nuts and general grade washersiii) BS 4604 Part 1:1970 - Specification for the use of High Strength Friction Grip Bolts in Structural Steelwork. Metric

Series. General Gradeiv) BS 4604 Part 2:1970 - Specification for the use of High Strength Friction Grip Bolts in Structural Steelwork. Metric

Series. Higher Grade (Parallel shank)v) BS 3692:2001 ISO metric precision hexagon bolts, screws and nuts - Specificationvi) ISO 898-1:1999 Mechanical properties of fasteners made of carbon steel and alloy steel

Coding of bolts with Grade 4.6, 8.8, 10.9 and etc. is still not available when both British Codes BS4395 and BS4604 published at year 1969 and 1970. However, the BS3692:2001 (version 1967 withdrawn) introduced the specification where bolt are categorized into Grade 4.6, 8.8, 10.9 and etc.. ISO 898-1:1999 described in detail the mechanical and testing requirements of these bolts.

The design procedure of HSFG bolts in the new BS5950: Part 1:2000 still refers to the BS4395 and BS4604. These codes only classified the bolt in general grade and higher grade. However, the general grade and higher grade bolts mentioned in the codes are still able to correlate to the latest BS 3692:2001 by its yield strength. Below are the yield strength comparisons of both general and higher grades of bolt with Grade 8.8 and 10.9.

Based on the table, it could be concluded that the Grade 8.8 Bolt in BS3692 is almost equivalent to the General Grade in

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BS4395. And Grade 10.9 Bolt in BS3692 is equivalent to the Higher Grade in BS4395.

The design parameter, Po minimum preload stated in BS5950: Part 1:2000 is required in designing HSFG bolts. The code cross references this parameter to BS4604, which consist of Part 1 and Part 2. In other words, both general (8.8) and higher grade (10.9) bolts can be used as HSFG. The only difference would be the value of Po, minimum preload, which is tabulated as per Table 2.

Table 1: Comparison of Yield Strength of Bolt

General GradeM12 - M24

[M27- M36]

Grade 8.8 Higher Grade Grade 10.9

1 Yield Strength 635 N/mm2[558 N/mm2]

640 N/mm2 882 N/mm2 900 N/mm2

2 Tensile Strength 827 N/mm2[725 N/mm2]

800 N/mm2 981 N/mm2 1000 N/mm2

Table 2: Po, minimum preload/proof load in BS4604, kN

Proof Load based on ISO898-1:1999 is also tabulated here for reference as per Table 3. It is noticed that the value is about 2% to 18% more than the proof load in BS4604. Nevertheless, as the HSFG bolt design in BS5950: Part 1:2000 is referring to BS4604, the proof load in Table 2 shall be followed.

M12 M16 M20 M22 M24 M27 M30 M33 M36

1 BS4604: Part 1General Grade

49 92 144 177 207 234 286 NA 418

2 BS4604: Part 2Higher Grade

NA 122 190 235 275 356 435 540 NA

Extract from Table 2 of BS4604 Parts 1 & 2:1970

Table 3: Po, Proof load in ISO898-1:1999 (coarse pitch), kN

M12 M16 M20 M22 M24 M27 M30 M33 M36

1 ISO898-1 : 1999Grade 8.8

51 94 147 182 212 275 337 416 490

2 ISO898-1 : 1999Grade 10.9

70 130 203 252 293 381 466 576 678

Extract from Table 7 of ISO898-1:1999

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The code only provides the required proof load to be achieved in order to design as HSFG bolt but does not provide the torque value. The required torque value for a specified proof load is governed by the finishing of the bolt (e.g. galvanizing, corrosion, lubrication condition and etc.) The coefficient of friction depends on the smoothness of the thread area in the bolts and nuts. High coefficient of friction will require higher torque value in bolt tightening. In this case, the torque energy provided for axial load in the bolt will overcome the thread friction. Usually bolt manufacturers would have recommended torque value to achieve proof load for HSFG bolt design in Friction Mode. However, it is not necessary to follow the recommended torque if the bolt is not designed as HSFG.

Table 4: Podger spanner as per BS2583:1955

Besides using the hand tool as described, bolts also could be tightened by a more efficient power tool. Some power tools are also equipped with preset torque value to achieve uniformity for bolt tightening. Designer could also fix the snug tight torque value as a proportion of the proof load torque value. This will give a clearer guideline at construction site for standardization.

4.0 Conclusion

a) Three fundamentals of bolt design are explained. It is essential to know the design philosophy for a connection before deciding on the required torque value.

b) Comparison of bolt is presented. It is concluded that the Grade 8.8 Bolt in BS3692 is equivalent to the General Grade in BS4395. And Grade 10.9 Bolt in BS3692 is equivalent to the Higher Grade in BS4395.

c) Bolts need to be tightened with an appropriate proof load if it is designed as HSFG bolt in Friction Mode. Bolts only need to be tightened as snug tight if it is designed as Shear/Bearing Mode.

Disclaimer

The Author has taken all efforts to ensure the accuracy and correctness of this paper, but the Singapore Structural Steel Society and the Author cannot accept any responsibility for damage, loss or other consequences resulting from the use of this paper.

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Snug tightening will be sufficient if the bolts are designed in Shear/Bearing Mode. The National Structural Steelwork Specification of BCSA states that “Bolts may be assembled using power tools or shall be fully tightened by hand using appropriate spanners in accordance to BS2583:1955. This may be defined approximately similar to a force of 25 kg (250 Newtons) being applied to the end of a podger spanner. Table 4 shows podger spanner as per BS2583:1955.

Meanwhile, snug tightening is defined by Australian code AS1511 as “The tightness obtained by the full effort of a man using a standard podger spanner”. Typical tools could be a 450mm long spanner for M20 bolts and 600mm long for M24 bolts. This is also quite similar to what have been described in the British Standard. Although this is not a scientific description, it is a practical and fair approach for achieving the required snug tightness.

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Members’ Night 2008

Synopsis

Falls from height are the major cause of death within the UK construction industry. At a presentation to the Singapore Structural Steel Society on 13th May 2008, David Thomas, Health, Safety and Environment Director at William Hare Limited, looked at some of the legislation covering this area and discussed ways in which the steelwork industry should manage the safety of employees working at height. In a presentation entitled “Recent innovations in safety during steelwork erection in the UK”, he looked also at some of the equipment introduced over recent years to aid safety during steelwork erection.

Background

The latest figures published by the UK Health and Safety Executive (HSE) covering fatalities at work make sobering reading. The number of workers fatally injured in 2006/07 was 241 (provisional), and this corresponds to a rate of fatal injury of 0.80 per 100,000 workers. (In 2005/06, the finalised figures were 217 and 0.72 respectively; these were the lowest annual figures on record). Whilst a long-term downward trend is still clear, the rate of decrease has slowed over the last 15 years and there has been very little change in the overall rate over the last five years. Of the main industrial sectors, agriculture and construction have the highest rates of fatal injury. Together, these two sectors account for 46% of fatal injuries to workers.

Falls from height accounted for 45 worker deaths in 2006/07. Whilst this was again a record low (in 2005/06, the finalised figure was 48), it remains the most common kind of accident causing fatal injuries. Clearly, more preventative action needs to be taken by the industry.

Provisional statistics show an increase in falls from height ‘major injuries’ to employees, from 3,385 (in 2005/06) to 3,409 (in 2006/07). However, the injury rate continues to decrease when all workers are taken into account (i.e. including the self employed). There were 3,750 ‘major injuries’ as the result of a fall at work (2006/07), representing a decrease of 43 on the previous year. Falls from ladders resulted in 12 deaths and 1,050 ‘major injuries’ (over a quarter of all major injuries as a result of a fall from height).

The Annual Members’ Night of the Singapore Structural Steel Society was held on Tuesday, 13 May 2008 at the Furama WaterFront Hotel. About 60 members attended. The highlight was a presentation on “ Recent Innovations in Safety during Steelwork Erection in the UK” by Mr David Thomas, Health, Safety and Environmental Director of William Hare, UK.

Recent Innovations in Safety during Steelwork Erection In the UK

SSSS members listening to Mr David Thomas Mr David Thomas of William Hare Limited presenting lecture on “Safety during Steelwork Erection in the UK”.

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Work at Height Regulations

Recognising the seriousness of the issue, and the need to reduce fatalities due to falls from height, the HSE introduced “The Work at Height Regulations 2005”. Consolidating and replacing all previous legislation on the topic the regulations also serve to extend the requirements of European Council Directive 2001/45/EC, concerning minimum safety and health requirements for the use of equipment for work at height.

The regulations place responsibility on employers, the self-employed, and any person who controls the work of others, to do all that is reasonably practicable to prevent falls from height. They advocate a planned and organised approach to working at height, where practical considerations such as fragile surfaces or the risk from falling objects are taken into account, as well as environmental conditions such as bad weather. The regulations also oblige duty holders to ensure that those involved in work at height are adequately trained and competent, plus that the equipment used for work at height is properly maintained and appropriately inspected.

Central to the duty of care placed upon those who control the work of others is the obligation to follow a simple hierarchy when commissioning work at height. The hierarchy states that duty holders should:

• Firstly, avoid work at height where they can;• Use work equipment, or other measures, to prevent falls where they cannot avoid working at height; and• Where they cannot eliminate the risk of a fall, use work equipment or other measures to minimise the distance and consequences of a fall should one occur.

For duty holders, the hierarchy encourages the consideration of a range of measures. For example, avoiding work at height could be achieved by using remote equipment; preventing a fall by incorporating equipment on site that prevents workers from getting near an edge; and putting in place measures, such as safety nets or other fall arrest equipment, that would mitigate the consequences of a fall should one occur.

Putting the regulations into practice

Whilst the regulations assign responsibility for work at height and provide simple guidance about preventative measures, different situations require different precautions. Industry has been quick to respond to the need to produce guidance and a number of trade organisations have published comprehensive and sector-specific advice on how to comply with the regulations. Examples include guidance provided by the British Constructional Steelwork Association (BCSA), the National Access and Scaffolding Confederation (NASC) and the Prefabricated Access Suppliers and Manufacturers Association (PASMA).

Meanwhile, to support the new regulations, the British Standards Institution has published a British Standard BS 8437:2005, Code of practice for selection, use and maintenance of personal fall protection systems and equipment for use in the workplace. Aimed at those seeking to comply with the Work at Height Regulations, it brings together personal fall protection best practice from a variety of sources including HSE representatives, manufacturers, research studies and training organisations. Those seeking good quality training are advised to ascertain whether the trainer in question is familiar with, and follows, the advice contained within BS 8454, Code of practice for the delivery of training and education for work at height and rescue.

Change is in the air

Prior to the introduction of the regulations, there was a consultation process and this served to focus minds on the challenges of working at height. This process has resulted in the development of a wide range of new safety products that are now becoming more widespread in practice.

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Before choosing equipment however, some fundamental principles need to be considered when selecting the type of equipment to use for work at height. In brief, the principles involve prioritising collective protective measures over personal protective measures and, where possible, using systems that prevent falls in preference to those that arrest them. In all situations, equipment should be selected that conforms to standards relevant to the intended use and equipment should only be used in accordance with the manufacturer’s user instructions.

Mobile elevating work platforms

Correctly selecting work equipment for any activity at height means being able to justify why safer alternatives required by the ‘working at height hierarchy’ have been ruled out. One example that illustrates adherence to these principles concerns the use of Mobile Elevating Work Platforms (MEWPs) – generally accepted as a collective measure that prevents a fall – during the erection of steelwork. On a congested site, it can be difficult to operate MEWPs and, inevitably, they have finite reach. It has been ‘custom and practice’ to climb on open steelwork, using fall arrest equipment (a personal measure and thus lower down the hierarchy). The introduction of the Work at Height Regulations challenged steelwork contractors to find ways of maximising the use of MEWPs.

Structural engineers William Hare Ltd. responded by introducing a temporary platform to support MEWPs, that moves progressively upwards through the structure as steel erection progresses. This enables workers to reach connections on higher floors in greater safety than previously. On the few occasions that it is still necessary to access open steelwork, and using fall protection equipment, this is controlled through the use of ‘task assessment briefings’. The briefing ensures that operatives are fully informed about the task before commencing and provided with the opportunity to discuss any problems they perceive, including emergencies and rescue should the worst happen.

Edge protection

In order to prevent falls, rather than mitigate the consequences, William Hare Ltd. has designed – for ease of use and installation – the Cellshield safety handrail system (patent pending, www.cellshield.co.uk), to offer safety for the construction industry. The system makes a positive contribution towards improving working conditions by reducing the risks to which the workforce is exposed. Furthermore, the system (designed and manufactured in compliance with BS EN 13374: 2004, Class A) has:

• Easy and speedy installation and breakdown;• Solid toe plate for excellent debris containment; and• High visibility.

Trailer edge protection

Three million people in Great Britain work on or near vehicles as part of their regular job. Getting on and off a vehicle to carry out loading/unloading operations and working at height on the vehicle are often viewed as incidental to the main job. Because of this, the risks involved may not be properly considered by both workers and their managers. The economic and human cost of the falls from vehicles has been estimated at over £36 million (2004/05).

There are around 2,000 reportable injuries each year due to people falling from vehicles. Working at height during the loading and unloading of transport vehicles in the construction plant industry presents a series of challenges in addition to

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those experienced by the general transport industry. In particular, a significant amount of loading and unloading takes place on construction sites, where it is often more difficult to use purpose-made gantries and ‘loading docks’. However, where working at height is required during the loading and unloading of any transport vehicle it should be carried out only following careful planning, which includes adequate assessment of the risks involved.

William Hare Ltd. has adopted a ‘trailer edge protection system’, developed and fabricated within the company (patent pending). It has a steel universal beam at its base, using welded galvanised steel standards (which include holes at various levels). The system is secured to the trailer using ties. Fitted within the standards are extensions, fixed in position by bolts in the lower standards. Fitted to the extensions are four horizontal guardrails. These are spaced at no more than 450mm, providing scaffold-like edge protection. The system can be raised up to 16 feet from the floor, with any adjustment being made using the holes/bolts in the standards, depending on the height of the steel load. This gives collective fall protection at different levels. The system is available in different sizes, to suit different lengths of trailer. In addition, the trailer bed is accessed using aluminium podium steps or, where space allows, a purpose-built gantry stair system at the rear of the trailer.

Conclusion

Ultimately, the Work at Height Regulations 2005 were written to effect a change in behaviour from management and workers with regards to work at height across a broad range of industry sectors. Whilst awareness of the regulation’s existence is currently relatively wide, in certain instances, practical application is poorly understood.

Work is ongoing by many organisations, including the HSE, to disseminate best practice and reinforce the message that everyone has the right to work in safety. Only when improvements in practice are adopted industry-wide will it be possible to judge this legislation truly effective.

References

UK Health and Safety Executive, www.hse.gov.ukThe Work at Height Regulations 2005, Statutory Instrument 2005 No. 735, www.opsi.gov.uk/si/si2005/20050735.htm#6European Council Directive 2001/45/EC, http://eur-lex.europa.euDirective 2001/45/EC of the European Parliament and of the Council of 27 June 2001 amending Council Directive 89/655/EEC concerning the minimum safety and health requirements for the use of work equipment by workers at work (second individual Directive within the meaning of Article 16(1) of Directive 89/391/EEC)British Constructional Steelwork Association (BCSA), www.steelconstruction.orgBritish Standard BS 8437:2005, Code of practice for selection, use and maintenance of personal fall protection systems and equipment for use in the workplaceBS 8454, Code of practice for the delivery of training and education for work at height and rescueWilliam Hare Ltd., www.williamhare.comCellshield, www.cellshield.co.ukBS EN 13374: 2004, Temporary edge protection systems. Product specification, test methods

Author profile: David Thomas, MSc, BSc(Eng), AKC, CEng, FICE, CFIOSH, is Health, Safety and Environment Director for William Hare Ltd. He is a Fellow of the Institution of Civil Engineers (CEng, FICE) and a Chartered Fellow of the Institution of Occupational Safety and Health (CFIOSH). Previously an HM Principal Specialist Inspector of Health and Safety (Construction) in the UK Health and Safety Executive’s Construction Division Technology Unit – latterly with the technical lead on work at height issues – he is a Member of the BCSA’s Health and Safety Committee and Deputy Chairman of British Standards Institution Technical Committee PH/5, Industrial Safety Belts and Harnesses.

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Corporate Members’ Night 2008

The 2nd Corporate Members’ Night was held at Spring Court Restaurant on Thursday, 15 May 2008. About 50 Corporate members attended the dinner cum get together. The Corporate Members’ Night offered an excellent opportunity for Corporate members to exchange ideas with fellow members as well as with Council members of the Society.The highlight of the Corporate members’ Night was a presentation by A/Prof Richard Liew on “New Guide on the Use of Alternate Steel Materials for Construction – How does it affect your business?”.

24th AGM

The 24th Annual General Meeting of the Singapore Structural Steel Society was held on 27 March 2008 at the Furama Waterfront Hotel at 6.30pm. About 60 members attended the proceedings of the AGM. Mr Tan Tian Chong, President of the Society presented the activities of the Society during the past year in his annual report. The Hon Treasurer presented the Treasurer’s Report to the members present. There was no election held for the Council as there was only one nomination for each vacant position. List of members elected to the new Council for 2008/2009 are shown on page 2.

Corporate members at the dinner table Corporate members at the dinner table

A/Prof. Richard Liew speaking to the Corporate members

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China Steel Design Strength (Design Strength reduced by 10%)Steel Grade Min Tensile Strength (MPa) Min Yield Strength Thickness ≤ (mm) Design Strength (MPa)Q235 375 235 16 215 40 205 60 200 100 190Q345 470 345 16 310 35 295 50 265 100 250

New Guide on the Use of Alternate Steel Materials for Construction – How does it affect your business?

Steel materials come from China, USA, Europe, Japan, Australia, New Zealand and many other countries. Steel sections are manufactured according to respective national standards such as GB, ASTM, API, JIS, AS, NZS and as such, mechanical properties and section sizes may differ from the design standards provided in the British Standards. In order to overcome this problem and to use steel manufactured from all these countries the Building and Construction Authority (BCA) had engaged a team of experts to develop a design guide as an addendum to the current design code BS 5950.

The team of experts has come up with a design guide entitled BC 1: 2008 “Design Guide on the Use of Alternative Steel Materials to BS 5950” which is now available for use. The BC 1: 2008 will guide designers to do design according to the BS 5950, with appropriate parameters to account for the mechanical properties of structural steel manufactured according to standards other than the British Standard. The BC 1:2008 also provides guidelines on quality assurance.

The BC 1:2008 can be purchased from the BCA counter at 2nd storey, Tower Block, MND Complex. A softcopy together with the explanatory notes can be downloaded from BCA’s website at:

www.bca.gov.sg/Publications/others/Design_Guide_on_use_of_Structural_Steel.pdf

www.bca.gov.sg/Publications/others/Explanatory__Notes_for_BC1-2008.pdf

During the Corporate members’ Night, A/Prof JY Richard Liew briefly explained the Design Guide. According to the Design Guide, the alternative steel materials will be classified into three classes based on verification against material performance and quality assurance requirements. Excerpts from A/Prof JY Richard Liew’s presentation is reproduced below:

• CLASS 1 : Certified steel materials with acceptable quality assurance – there will be no reduction in strength.• CLASS 2: Non-certified materials meeting tests requirement – 10% reduction in strength.• CLASS 3: Non-structural steel members which do not meet at least one of the two requirements – Design strength severely

downgraded, eg. to 170mpa (16 mm).

Factory production control certificates• The factory shall produce a certificate issued by an independent third-party certification agency acceptable to or recognized

by BCA as an attestation of the factory production control system in meeting the given requirements.• The purchaser shall obtain a validated copy of such certificate directly from the manufacturer or through the stockist.

Manufacturer test certificates• The manufacturer shall produce an authenticated test certificate as an additional layer of quality assurance on the alternative

steel materials delivered.• The purchaser shall obtain such certificate directly from the manufacturer or a validated copy of such certificate through

the stockist.

SSSS Steel Material Qualification & Certification Scheme• Stockists and fabricators who buy direct from manufacturers and establish their own in-house quality assurance

system.• SSSS acts as third party to audit the company.• Steel purchased from the certified stockists and fabricators may be classified as Class 1.

A/ Prof JY Richard Liew gave some applications of alternative steels used in Singapore. They include hanger structures and the Singapore Arts School where Chinese steel grade Q345 were used. In conclusion he said that “In reality, it is not the standard that the material is certified to pass but the actual product, its properties and performance that matters!”

24th Annual Lecture & Dinner

Tubular Structures in the Avant-Garde of ArchitectureLecture by Prof. Dr. Mick Eekhout

Architecture is becoming more and more sculptural in form, material and detailing. Tubular structures are very versatile in the design phase and can be moulded to fit in sculpturally designed roofs as circular hollow sections can be bent and welded and always keep their circular cross section, omni-valent in many directions. They stimulate shaping the technology of free form architecture. Many of the recent projects of free form architecture were not possible without tubular hollow sections. Worldwide projects are analysed in the relationship of architecture and technology.

Prof. Dr. Mick Eekhout • 1950, born The Hague.• 1973 bouwkundig ingenieur / building engineer TU Delft (Cum Laude). • 1975 start architect’s office Mick Eekhout.• 1978 start Octatube Engineering. • 1983 start Octatube Space Structures bv/International bv, specialized in space structures and glass

facades/roofs. Average 50 staff and 50% turnover in export. Worked with Renzo Piano, Frei Otto, Norman Foster, Moshe Sadfdie, Shigeru Ban, Erick van Egeraat, Benthem + Crouwel, Cepezed.

• 1989 PhD (cum laude) under prof. Jaap Oosterhof with dissertation “Architecture in Space Structures”.

• 1986 foundation Delft Design, association of TU Delft designers. • 1988 co-foundation of Booosting. • 1992 professor Chair of Product Development TU Delft. • 1995-1998 and 2003-2008 research nestor. • 1999-2002 department head Building technology design. • 1997-2003 member Raad van hoogleraren TU Delft advising rector magnificus. • 2000-2007 chair of Research Advisory Board Industrial Design Engineering TU Delft. • 2002 Pioneer’s Award University of Surrey, department of Space structures. Wrote 10 books (methodology, product

development, tubular steel structures, glass structures, aluminium) and over 200 publications. Currently 8 books in preparation. Chair holds 20 PhD students.

• 2003 elected full member Royal Academy Science and Arts/KNAW and Academy for technology and Innovation. • 2005/2007 organized congress Delft Science in Design 1/ 2 on multi-disciplinary Design on TU Delft. • 2005-2008 Special Professor of Space Structures at Nottingham University. Several awards. Kho Liang Ie Award for

Industrial Design. • 2007-2008 Assignment to form a Dutch 3TU research umbrella organisation ‘Spearhead Building Innovation’ for the

Dutch building industry.

The 24th Annual Lecture and Dinner of the Singapore Structural Steel Society will be held on Thursday, 28th August 2008 at 6.30 pm at the Meritus Mandarin Hotel, Singapore. Prof. Dr Mick Eekhout will be delivering the Annual Lecture. Members and their guests are cordially invited to attend the event. For more information please contact our Secretariet at Tel. 63921381.

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New Products & Services

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