Visual Observation and Measurement of Aerial Stress Distribution Under a Rigid Strip Footing

Recent advances in tactile sensor technology have produced very thin sensors allowing the simultaneous measurement of normal pressure at multiple points. Such sensors were used under the base of a laboratory model of a rigid strip footing (76.2mm x 609.6mm). The developed contact stresses are peaked along the centerline and lower along the edges. This distribution, visually observed for the first time, matches well the- anticipated theoretical distribution and is quite different than the even distribution routinely assumed in design. The insight obtained by the observed contact stress distribution can assist in a better geotechnical and structural economical design of shallow foundations.