Circular-Plate Load Tests on Bounded Cemented Layers above Weak Cohesive-Frictional Soil

Abstract

The usage of soil-cement reinforced layers to bear shallow foundations is a viable option in low-bearing-capacity soils. Existing methodologies that can determine the bearing capacity in such cases tend to consider the cemented layer’s bounds to be infinite, depending solely on the ratio between the footing width and the layer’s thickness. The present study intends to assess the influence of the reinforcement width on the load-settlement behavior of a circular steel footing resting on square-edge soil-cement layers bearing on a weak highly porous residual soil. Static load tests were carried out on footings (diameter of 300 mm) resting on sand-cement reinforced layers with distinct areas (edges of 450, 600, and 900 mm) and constant thickness of 300 mm. The results have shown two distinct failure modes that rely on the cemented layer’s width. A punching mechanism was observed for the two smaller reinforcement’s layers and they did not fail. The 900-mm square cemented layer, on the other hand, had a failure that was initiated by the formation of tensile cracks and fissures in the center of its bottommost segment. This study highlights the importance of considering the soil-cement layer’s width in the bearing capacity estimation of footings resting on treated layers above weak cohesive-frictional soils.