Heavy vehicle rollovers Understanding the fundamental reasons why rollovers occur and applying best practices to prevent them

Heavy vehicle roll-over prevention program.

Aim to -

•Reduce rollovers crashes by creating awareness •Reduce rollovers crashes by creating awareness

to all stakeholders.

•Preserve driver

•Reduce resultant trauma.

•Improve productivity.

•Reduce impact on environment.

•Reduce impact on community.

What is the “Cost of a roll-over”?

Most operators say around

70k, before the truck or driver

are repaired.

Spate of rollover crashes.

� 16 log truck rollover crashes in the six months prior to implementation.

We needed an immediate and profound effect.

Analysis of statistics.

Crash investigation. (it was found that in most cases drivers were not

breaking the law).

Input from- Drivers, industry, Police, trailer manufactures, Input from- Drivers, industry, Police, trailer manufactures,

tow truck industry.

Analysis of overseas and other studies.We found that the knowledge had not been passed down to the people at the

coal face.

An awareness program designed to give the industry ownership was developed

and implemented.

In the six months after implementation- zero rollovers.

Truck roll-over crash prevention program.

AWARENESSGive you a crash course in understanding what

happens during a rollover

� Identify and develop an understanding of the

causes.

�It is vital that we all understand this if we are going

to be able to work together to prevent them.to be able to work together to prevent them.

The key to reducing the number of rollover crashes is

that-

Most rollovers, happen at fairly low speeds and

involve single vehicle only crashes.

Focus on rollovers that cause crashes.

Factors that contribute to these rollovers.(1%)

Load restraint test- It’s the weight and COG over the trailer axle that matters. The trailer goes first.

Factors that influence roll-overs.

� Roundabout size

� R-A-Bout Camber

� Lack of time intersection

� Intersection size

� Tight Corners

� Wrong Camber

� Road condition

� On ramps

� Camber change in turn

� Road litter

� Engine failure

� Missed gear

� Inappropriate selection

� Lane change downhill

� Suspension condition

� Tyre condition

� Gravity

� Speed

� Changing direction

� Acceleration.

� Driver experience.

� Sloshing.

� Load movement.

� Type of load.

Gravity

Speed

Friction � Off ramps

� Load location

� Load viscosity

� Load packing

� Low tare weights

� Gross weight

� Load heights

� Bed heights

� Trailer format

� Tyre condition

� Tyre pressure

� New tyres

� Axle alignment

� Suspension type

� Time pressure

� Other road users

� Mobile phones

� Road knowledge

� Centrifugal Force

� Restraints

� Friction

� Stiction

� Centre of Gravity

� Driver alertness

� Sun

� Wind

� Brake condition

� Couplings

� Number of trailers

Centre of Gravity (COG)

Centrifugal Force

FrictionSuspension

Slide 5 The forces

centrifugal

Centre of gravity

suspension

20 T

gravity

Centre of gravity

friction

suspension

Centre of gravity (COG)

20 T20 T

20 T

Centre of gravity

20 T

Speed- Centrifugal force.

� If a vehicle is forced to take evasive action these forces are further multiplied.

What to do:

If you double your speed, the overturning force will be 4 times higher.

As the speed increases the trailer tracks wider and forces increase on rear

axle. This means that a slight increase in speed can be critical.

Do you know your load?

Know your load.

COG

Know your load.

Know your load.

Slosh factor.

� Cornering

Centrifugal

Cow

Centrifugal

Force.Slosh effect

Know your vehicle- Stability.

Load height

- 3.9m

4.6m

- 3.9m

Bed height

- 1.3m

Track width 2.5m

Bed

height

1.3m

COG

Know your vehicle

Load height

- 4.3m

4.6m

- 4.3m

Bed height

- 1.7m

Track width 2.5m

Bed

height

1.3m

Locations-Roundabouts, on ramps, s bends, sharp and off camber corners, poor road shoulders, intersections………….

Speed on corners.Advisory signs

These signs include a recommended

speed and a diagram of the corner’s line.

The recommended speed reflects a

maximum of 0.22g of sideways

acceleration on any vehicle following a acceleration on any vehicle following a

constant, steady path, at the posted

speed, through the corner. If the SRT of a

vehicle were 0.22g it would roll over

while negotiating the curve at the

advisory speed.

Example- In a truck with an SRT rating of

0.25g, taking this corner at 27kmh is

likely to lead to roll-over.

(.35 SRT is approx 32kmh)

Loading- Load tight, low and forward.

Centre of Gravity- it is that simple

All this leads to the 1k factor.If you are driving close to the limit----

� 1 % factors come into play……..

� Unknowns … environment, other road users,

� So, as little as 1 kph extra will make you roll overover

� If you are aware, and you add more than the 1kph space, that is give yourself decent headroom to allow for unknowns, you will get home without a roll over.

Case History

1%- Contributing factors

� Home problems� Wild cattle� 2 pickups- not loaded quite right.� Hard to load-not loaded quite right.� New tyres� Road works� Road works� 100 mm shoulder- 150mm overall 5-6 deg� Sw wind� White line wrong spot� Squeezed by oncoming vehicle� Left turn to straighten� Past apex� Rh turn� Slosh- cattle moved

Driver vs contributing factors

Roundabouts

Intersections

Corners

Sloshing

Load shift

Gravity

Speed

Friction

Centre of gravity

Suspension

Load shift

Timelines

For a driver a roll-over is a personal and life changing event.

Roll-overs are typically a single vehicle incident.

In fact it comes down to- DRIVER- VS -CONTRIBUTING FACTORS.

Every time we send a truck out on the road we rely totally on the drivers

skills and experience to get the load safely to its destination.

The message is for all parties in the transport chain to do what they can

to eliminate, reduce or control as many of these factors as we can.

Compromise

� The transport industry runs on a best fit compromise of-

� Cost

� Efficiency

� Safety� Safety

When we get

extra mass,

“The only way is

up”

Compliant CrashesRegulations RolloversLegal Prangs

� WE MUST UNDERSTAND THAT JUST BECAUSE A TRUCK IS LEGAL- ITS NOT NESSECCARILY SAFE. THE SAME IS FOR OUR FREIGHT TASK. LEGAL IS NOT NESESSARILY SAFE.

We all must work together, not just look at the driver, the load, the truck, the job, or the journey, or even “whole of route approach”. Lets look at the whole “freight task” from its very inception until well after the product has been delivered and value added.

From this!!!!…………….To this!!!

Bed height 1.7m to 1.3m

From this???

To this!!!!!

From this???? To this!!!!!

Receiver

Consignors Loader

Unloader

Agencies

Vehicle manufacturers

Sellers

The public

AWARENESS

The harvester

Local councils

Road safety groups

Media

Operator

Driver

Family

Transport managerBuyers

Customers

Communities

Regulators

Road builder

From this!!!!…………….To this!!!

Bed height 1.7m to 1.3m

Logging industry actionsWhole of freight task and beyond approach to a very successful outcome.

� Roll-over awareness sessions for all parties in the chain.

� Change vehicle design, low bed heights and drop decks

� Cutting wood specifically to length for each truck

� Changes in loading and unloading practices

� Use of EBS (RPS)roll-over stability braking systems

� Route planning and Traffic Management Plans.

� Use most appropriate vehicle

� Use of longer vehicles and Bdoubles. (First & Last Mile)

� Voluntary load height limits on higher risk roads

� Safety alerts for higher risk roads

� Development of a Code of Behaviour

� Knowledge sharing by all. Induction and mentoring program

� Consignors and receivers giving more flexibility in their requirements to assist in the complete task.

“This really is a great opportunity for a group of such influential people to make a real

difference.”!!!!!

Driver vs contributing factors

Roundabouts

Intersections

Corners

Sloshing

Load shift

Gravity

Speed

Friction

Centre of gravity

Suspension

Load shift

Timelines

For a driver a roll-over is a personal and life changing event.

Roll-overs are typically a single vehicle incident.

In fact it comes down to- DRIVER- VS -CONTRIBUTING FACTORS.

Every time we send a truck out on the road we rely totally on the drivers skills and experience to get the

load safely to its destination.

The message is for all parties in the transport chain to do what they can to eliminate, reduce or control

as many of these factors as we can.

Case History