Tremie

The tremie concrete placement method uses a pipe, through which concrete is placed below water level.

The lower end of the pipe is kept immersed in fresh concrete so that the rising concrete from the bottom displaces the water without washing out the cement content.

Concrete is often poured through a tremie pipe in order to build caissons, which are the foundations of, among other things, bridges that span bodies of water.

Tremie methods are employed for materials other than concrete, and for industries other than construction. For example, bentonite slurries for monitoring wells are often emplaced via tremie pipe.

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