Experimental studies on model pile foundations reinforced by hard inclusions

Abstract

One of the ways of pile foundation reinforcement is the method of high-pressure group injection, which has been widely used in construction practice in the cities of Siberia (several dozens of objects). It consists in injecting a movable cement-sand grouting compound into the soil under pressure exceeding its structural strength. As a result, solid injection bodies reinforcing the ground base are formed after hardening. In such a case, when breaking the soil, it is not always possible to make entire masses optimal for reinforcement because they are divided into separate rigid inclusions. Various schemes of inclusion layout are analyzed in this paper. The experiments were carried out in a small soil hod, which was filled with medium-grained loose sand. The piles were modeled by metal rods, gravel grains of various sizes and shapes were used as injection bodies. As a result of the analysis of the experiment results, the approaches to the designation of optimal layouts of rigid inclusions when reinforcing the pile soil foundations by high-pressure injection of mobile cement-sand mixtures were defined.