For dike, levee, seawall or protection dam
Under certain conditions, the erosion shear failure as well as the overflow can be averted by massive use of sandbags to increase the dike’s height or its internal proper weight. However this procedure is extremely complex and requires the deployment of large personnel in very short time.
Short-term sealing of the tailing dam in the event of a disaster by usual specialized foundation engineering processes like sheet piling, clay cut-offs, jet-grouting, large diameter pile method or diaphragm walls are usually out of question due to the high risk of instability of the structure by the sole load of the application equipment and the non-immediate effectiveness of the measures taken.
Procedures with the use of a seal by subsurface injection with cement mortar cannot be applied in the event of a significant flow through the dike, due to the dilution of the cement emulsion by moving water flow.
Filling and solidifying as an emergency measure – Flood protection
Case study: Deep water seaport permanently stabilized
The immediate measure from the building JV was to commission a full stabilization of the sand mass with deep injections on the landside, behind the sheet pile curtain. The main problem was the access though the quay concrete plate were the only available openings were in form of 80x80cm passages. It was not possible to make traditional boring due to the fact that underneath the plates there were “discharge chambers” filled with water that allowed the works only via boat on the waterside.
The only alternative was to use manchette pipes (“tubes à manchette”, in short “TAMs”) coupled with press spears that were pushed into the sand down to 18m depth for the injection. To fully saturate the sand, 3 spears were foreseen to every sheet pile chamber. As injection good only an extremely low viscosity polymethil acrylate gel could be used, considering also the environmental safety of the area. TPH’s RUBBERTITE with DIBt certification for curtain injection and environmentally non-hazardous could be used without any problems.
The stabilized and consolidated sand was not washed out from any point of the 1725m long sheet piling of the quay wall and the rubber elastic consistency of the material employed guarantees a permanent closing of all gaps in the joints.