Basics To Pouring Concrete
It is important to have all concrete mixes specified as “pump-able” prior to any concrete pours. There are mixes that do not pump at all or cause the pump lines to clog- big problems if you have 8 trucks arriving on the job ready to discharge concrete. The aggregate diameter must not exceed 1/3 of the inside diameter of the pipeline. For small line pumps, it is recommended that inside diameter of the pipeline be 4 times the largest aggregate size.
Concrete Delivery Area
The concrete truck delivery area, including the area around the pump hopper, should be set up to ensure that:
- Workers are safe from other vehicles
- Adequate lighting is provided if pumping in non-daylight hours
- Appropriate signage is posted
- There is clear access for delivery trucks
If multiple concrete deliveries are expected and on-site traffic management is not provided, only one delivery truck should approach and discharge into the hopper at a time.
If a designated on-site traffic controller is provided, the following safety rules should be followed:
- All personnel connected with discharging from concrete trucks are to wear appropriate high-visibility safety vests
- The appointed signaler and operator should be instructed on:
- The use of the code of signals in Appendix A
- The use of any communications device supplied
- Any special risks on the site, e.g. overhead obstructions
- The traffic controller and truck driver should be in positions which prevent them from being caught between the hopper and a reversing truck
- The traffic controller should warn the driver at the pump of the presence of another truck being reversed into position
- The traffic controller should be in a position visible to the reversing driver and where the hopper area can be observed
- Delivery drivers should ensure that their vehicles remain clear of the discharge area until signaled to reverse into position by the traffic controller
- If the driver loses sight of the traffic controller when reversing into position, the driver should stop immediately.
If the general public can come close to any part of the concrete pumping operation, the following options are recommended:
- Directing the public to an alternative footpath, or providing an alternative pathway
- Installing protective screens to prevent concrete splashing on members of the public
- Erecting barricades and warning signs that are compliant with WSBC requirements
For longer concrete pumping operations, pedestrian controls should be of a more permanent nature.
The principal, in consultation with the pumping contractor, should provide adequate traffic control measures to comply with WSBC requirements.