Ductile Pipe Piles

[tclat]

Dear All,

I am currently reviewing piling options for a 3 storey structure in a high seismic zone. One of the options that we have been asked to review is a mini pipe pile. See attached. The system comes from Germany and Austria and the pipes are 180mm in dia, come in 5m lengths and is driven with a special hammer connected to a large excavator. The joint is a simple friction bell and spigot type. link below.

Because we are in a seismic zone, the geotechnical engineer recommends grouting the pipe completely both on the inside and outside of the pile using a special shoe. He also recommends using a continuous length of rebar over the entire length of the pile to reinforce the joint. Our piles on average are 12m long and with this setup, he recommends that we can have a tensile capacity of up to 225kN.

Questions,

1. Is any one familiar with this system and its applicability in a seismic zone?
2. Is it really feasible to grout the outside of the pile using this technology?

Comments would be great.

 

[hokie66]

See my latest answer in the structural forum. There does not seem to be much familiarity with the system from engineers who normally contribute here. Feasibility of grouting on the outside of the pile would depend on the material through which the pile is driven, but as this is a displacement pile, normally tensile capacity is based on friction between the pile and soil. The internal reinforcement would have the purpose of connecting the joints in tension, so the reinforcement would have to be strong enough to take your 225 kN. As in the other thread, the piling contractor and/or manufacturer needs to be leading this discussion.

 

[BigHarvey]

System used in Europe (mainly Switzerland, Austria...). It's simple and works well. It's not a special hammer which is used to drive it but a hydraulic rock breaher but a conventional hammer can be used. It works in seismic areas (approved at least for french codes, you just need to concrete Inside the tube with a continuous reinforcement. Grouting the annulus is done at the same time you drive the pile but there is no obligation to do it, but it increases the capacity of the pile.