Vehicle Roll-over - soe.org.uk

1 Vehicle Roll-overProduced by IRTE, a Professional Sector of SOES ponsor: SOE (Society of Operations Engineers) is a professional membership organisation representing some 15,000 individuals and companies in engineering. It supports and encourages members throughout their careers and is committed to their ongoing growth and personal a network of trustees, industry partners and members, SOE promotes best practice in operational and health and safety initiatives. SOE offers members continuing professional development and support throughout their careers, providing definitive recognition for both achievement and status.

2 The organisation is a Licensed Member of Engineering Council and can nominate members for Engineering Council registration at EngTech, IEng and CEng levels. SOE represents the Professional Sectors IRTE, IPlantE and BES and developed the technician-licensing scheme, irtec. IRTE (Institute of Road Transport Engineers), one of the most respected names in UK transport, has always been recognised as an impartial voice of the publishes an industry-leading technical journal, Transport Engineer, every month. Now online contains a searchable editorial archive, daily online news updates, a supplier directory, e-zine newsletter, jobs, events, whitepapers and much more.

3 IRTE also hosts regular technical seminars and forums and works alongside the DfT to promote efficiency and best practice. Recent events include biofuels, trips and falls from vehicles, truck operation, fuel efficiency and the Road Safety Act. IRTE s technical committee also produces regular industry guidance on key topics. See pages 14-15 for IRTE s range of guidence documents, all of which are free to download from members come from a wide variety of transport-related roles. These include workshop managers, fleet engineers, transport managers, company directors, apprentices and technicians in the light and heavy goods Vehicle and bus and coach sectors.

4 This publication is a result of work conducted by the IRTE Technical, Publications and Government Liaison Committee. If you are interested in becoming involved with the committee, please contact Ian Chisholm, Head of Operations & Communications on 020 7630 1111 or email guide was first published by the SOE in April 2011 ISBN: 978-0-9555685-6-5 Author: Nicholas Edwards Editor: David Jones Design and Guide Coordinator: Sarah Prest 2011 Society of Operations Engineers3 PrefaceIn 2008, there were 9,040 reported accidents in the UK involving large goods vehicles (rigid and articulated).

5 Almost 5% of these accidents related to Vehicle Roll-over . Although Roll-over accounts for only a small proportion of Vehicle accidents, it is the manner in which these occur and the outcome that is the concern. Vehicle Roll-over also costs a great deal of money - recovering vehicles, repairing vehicles and roadways, replacing damaged or lost loads; incidents may result in serious injury or death of the driver or third is particularly evident in the road transport industry, due to the physical nature of large goods vehicles (LGV) and passenger carrying vehicles (PCV). The shape and structure of LGVs and PCVs often leads to a high centre of gravity, which in turn increases the chances of the Vehicle rolling over.

6 Semi articulated LGVs are at higher risk than rigid, due to the coupling. Usually, the trailer is supported in three places, which reduces the stability of the Roll-over typically occurs during cornering, where centrifugal force, acting through a Vehicle s centre of gravity, causes it to lean. The magnitude of the centrifugal force will increase as speed and turning angle increases. Roll-over Threshold is the term for a truck s ability to resist Roll-over . The lowest point of centrifugal acceleration, which causes the truck to tip over when travelling consistently along a curved path, derives this value.

7 A Vehicle s Roll-over Threshold can be directly affected by the way in which the Vehicle is set-up (loads, tyre pressure, suspension etc.)ESP switched offImage supplied by Knorr-Bremse UK4 SECTION PAGEWhy do roll-overs occur? 5 Roll-over prevention 8 Future developments 11 Legislation 12 References

8 13 IRTE publications 14 Sponsor 16 Contents and appendices5 Why do roll-overs occur?Below is an outline of the primary reasons for Vehicle Roll-over to occur:Adverse weather conditionsThe most obvious weather condition associated with Vehicle Roll-over is high winds. The probability of a Vehicle rolling over in high winds is increased in situations where there is a high centre of well as high winds, weather that affects the road surface (snow, rain, ice) can all contribute to Vehicle Roll-over , as the contact between the tyres and road surface is Some high-sided trailers are more susceptible to Roll-over .

9 AvoidanceThis type of incident is where the driver attempts to avoid a hazard in their path, and turn too abruptly, resulting in a possible over turn situation. The over turn situation is usually caused through the correction of the initial avoidance manoeuvre, resulting in cumulative pendulum action, which may increase or decrease as the Vehicle continues in a straight line. This pendulum action is enhanced with high centre of gravity vehicles, such as double deck trailer units, car transporters, liquid or powder tankers a driver to have maximum control over a Vehicle , it is very important the braking system be in correct working order.

10 Anti-lock Braking Systems (ABS), Electronic Braking Systems (EBS) and Electronic Stability Programs (ESP) all help in preventing Vehicle Roll-over , as they can automatically adjust the braking pattern for each wheel, possibly giving the driver greater control. The combined effects of ABS, EBS, ESP, yaw rate sensors and steering angle sensors can apply corrective action to assume control from the driver and reduce the chance of stated, a large proportion of Vehicle roll-overs occur whilst cornering. Due to the higher centre of gravity, and low Roll-over Threshold, entering a corner at excessive speeds encourages the Vehicle to lean and thus Roll-over .