Methodology for measuring pressure at the contact surface between a column footing model and a soil layer limited by a rigid base using Earth pressure cells

Abstract

The design of all building structures largely depends on the foundation support system, i.e., the relevant actions for structural design depend on soil–structure interaction. This paper describes a methodology for measuring pressures at the contact surface between a column footing model and a soil layer limited by a rigid base using earth pressure cells. The purpose of the research is to assess the reliability of the obtained results representing contact stress distributions between the interacting components under laboratory conditions. The concept of a reduced-scale footing model is presented, along with the procedure for preparing and installing earth pressure cells in the soil, with special emphasis on their position and data acquisition method. The main factors affecting measurement accuracy are also discussed, including soil characteristics, geometric and material properties of the tested footing model. The aim of this paper is to define an experimental procedure for a footing model and a soil layer limited by a rigid base that can serve as a basis for further experimental research and validation of numerical models. The reliability control of the measured contact stresses using earth pressure cells is based on comparison with analytical results. This experimental study examined contact pressures between a footing model and compacted sand using earth pressure cells. Measured pressures deviated significantly from calculated uniform values in the first test (48.3%) due to installation-induced soil disturbance, but improved to an acceptable 9.2% in the third test with proper surface preparation. The load–pressure relationship remained nearly linear across all measurements, consistent with sensor specifications.