Temeltek is the most experienced Turkish Contractor offering Diaphragm wall technique, having constructed diaphragm walls for several desalination projects, road tunnels and urban basements through out the history of our company. We have a large range of specialist equipment for diaphragm wall construction and our engineering personnel are highly professional in anticipating the project requirements.
A diaphragm wall is a concrete Wall reinforced and casted by the use of supporting bentonite slurry. which prevents the trenches and foundation from collapsing during excavation. The slurry forms a thick deposit (the cake) on the walls of the trench which balances the internal hydraulic forces and prevents water flow into the trench. Walls generally range in thickness from 500mm to 1500mm and can be excavated to depths of 50m or more.
Diaphragm walls are often used in congested areas or where the excavation depth is very deep which would otherwise require excavation of much greater soil volumes to provide stable battered slopes. They are well suited for deep basements, underground rail stations, rail car unloaders, tunnel approaches, pumping stations and such like. Trench stability is maintained by the use of panels of a length not exceeding about 7 m, although this can vary according to the type of soil and the neighbouring ground.
When there are structures adjacent to the worksite, the minimum distance between the main surface of the building, including its foundations, and the external panel of the wall being built will be equal to the thickness of the guide-wall. When a panel has been excavated, the reinforcing cage is lowered into the trench, which is filled with slurry that has been pre-treated in order to minimise ground particles in suspension. The trench is then filled with concrete from the bottom up by means of tremie pipes in order to create panels.
The joint between two panels can be constructed in two different ways including using a steel formwork section that will provide a sealing system between the panels and will provide guidance for the excavation grab and using the hydrofraise, which is possible to bite into in the concrete of the adjacent primary panels, then making a direct concrete to concrete interlock. The conventional widths of diaphragm walls are 0.50 m, 0.60 m, 0,.80 m, 1.00 m, 1.20 m and 1.50 m.