Assessment of adjacent foundations consequences and solutions for remediation via physical modeling

Abstract

In modern construction projects, a significant challenge arises from the consequential impacts of developing adjacent structures. The interplay of stresses within neighboring foundations can lead to a range of issues, such as deformation, leaning, cracking, instability, and various other damages. Among the numerous factors affecting foundation interaction, this research uniquely focuses on the impact of soil type, utilizing precise physical modeling through a 1 g testing apparatus. To enhance measurement accuracy, image processing techniques are employed in conjunction with LVDT and displacement gauges. The study systematically investigated the roles of five distinct deposit types—soft clay, loose sand, silty sand, loess, and low-compacted Tehran clay—in the manifestation of settlement and tilt arising from foundation adjacency. Subsequent to this evaluation, a comprehensive examination of strategic measures aimed at preventing and mitigating damages resulting from foundation interaction is undertaken. For silty sand, a detailed comparison of five remediation techniques is conducted, while in other soil types, only densification method is applied to address settlement and tilt. The comparison is based on the reduction in settlement and tilt, after the implementation of remediation methods under new foundation. Results highlight the crucial role of soil properties in determining damages from foundation adjacency. Notably, Tehran soil with low density exhibits maximum settlement in its loose state, while loess soil shows the highest settlement in the dense state. The exploration of soil improvement methods reveals that diaphragm walls and pile groups are influential in minimizing tilt and settlement of existing foundations, while pile groups proved to be the best remediation method in controlling displacements of new foundation.