Test Pit Facility

Test Pit Facility

The Institute for Geotechnics offers a testing facility for different types of geotechnical investigation. It is particularly suited for soil-pile interaction studies, where it is able to close the gap between small-scale testing, on one hand, and very rare and expensive in-situ testing, on the other hand, by allowing for medium- to large-scale model testing. The facility also overcomes some of the limitations of centrifuge testing such as scalability of the soil/soil grain and, thereby, the difficulty in observing some phenomena like soil-water interaction.

The facility has a total length and width of 19.5 m and 5 m, respectively. It has two parts: a 6 m deep pit with plan dimension of 5 m x 5 m and a shallower pit 3 m in depth and plan dimension of 14.5 m x 5 m. For both pits, mobile walls can create smaller sections to allow for smaller-scale tests.

The installation is equipped with vertical and horizontal actuators that can transmit static and dynamic force or displacement. Maximum vertical and horizontal static load capacity is currently 200 t and 50 t, respectively, but higher loads are feasible. Both the vertical and horizontal loading frames are movable and can be positioned at various places across the pit to accommodate different test and loading conditions. The installation is also equipped with various measurement devices.

A large soil handling system is available for soil model construction. For the model piles, installation can be by vibration or hammering into the soil or they can be “wished in place” by placing the soil around the preinstalled pile. With our facility, high-quality testing and validation of new and existing numerical models on soil-pile interaction is possible.

Overview of the test pit facility

Close view of the vertical loading frame

Close view of the 6m-depth pit