Ideally, each tremie pipe in a diaphragm wall construction project should be fed by a dedicated concrete truck. This ensures a consistent and controlled flow of concrete, minimizing the risk of operational issues. However, in situations where only a single concrete truck is available, careful distribution of the concrete is crucial.
Dumping all the fresh concrete into a single tremie pipe while leaving others empty can lead to an uneven build-up of concrete at the base of the filled pipe. This can create a small mound or “hump” that is susceptible to collapse. If this hump collapses, it can trap slurry within the diaphragm wall, compromising its integrity and potentially leading to structural problems.
To avoid this scenario, the concrete should be evenly distributed among all the tremie pipes. This ensures a balanced and controlled flow of concrete within the trench, minimizing the risk of hump formation and subsequent slurry entrapment. Even distribution also helps maintain consistent concrete quality and facilitates a smoother construction process.
In conclusion, while a dedicated concrete truck for each tremie pipe is ideal, it’s not always feasible. When working with a single truck, meticulous attention must be paid to the even distribution of concrete across all tremie pipes. This practice prevents uneven concrete buildup, mitigates the risk of slurry entrapment, and ensures a successful diaphragm wall construction project.