Sheet piling quay walls of the Jade Weser Port were successfully waterproofed through resin injection
Due to the difficulties in the pressing of 40m long sheet pile elements inevitable major leakages showed up in the joints during the excavation phases of the port basin. These openings had as consequence the wash out of the sand due to waves and tides from within the quay chamber. The problem grew up to unsustainable dimensions after the high tides and the storms in autumn and new year.
The sand washed out of the inner basin would accumulate on the opposite side of the pile curtain and in the long run could interfere with ship traffic. Permanent excavation works were intensively used as corrective measure but also the stability of the sheet piling itself could be compromised as well as the one of the plate supporting piles within the quay area.
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.