Load Settlement Response of Footing Placed over Buried Flexible Pipe through a Model Plate Load Test

This paper presents the load-settlement response of a surface footing placed over buried flexible pipe through model plate load tests. Experiments are conducted in a rectangular box after placing a model footing on the surface of sand placed at two different relative densities. Combination of tests were performed, such as, (1) model footing placed over sand compacted at low relative density ($\text{RD}=50\%$) and model buried flexible pipe (PVC pipe) placed at 0.5 B and 1.0 B depth, and (2) model footing placed over sand compacted at high relative density ($\text{RD}=88\%$) and model buried flexible pipe (PVC pipe) placed at 0.5 B & 1.0 B depth; where B = diameter of the model footing. The results of the model plate load test provide useful interpretation about the combined behavior of buried flexible pipe–soil system in terms of load-settlement response. The influence on the bearing capacity of sand in different relative densities and that caused by the presence of a buried flexible pipe beneath the footing is also discussed. Experimental results are also verified numerically using the two-dimensional finite-element tool PLAXIS, and results are discussed in light of the experimental findings. Furthermore, a soil nailing technique is also explored experimentally and numerically to establish its usefulness in terms of improving the bearing capacity of the buried flexible pipe soil system in a given sand medium.