A Systematic Research on Observations of Box Foundations for Four Multi-storied Buildings in Shanghai

This paper based on the results of observations of box foundations for four multi-storied buildings in shanghai, ranging from 10 to 12 stories, is divided into three parts. The first part deals with the deformation properties of foundation soil during the following three stages:（a） When the foundation pressure increased from unloading condition （due to excavation） to the orignal overburden pressure, （b） When the net foundation pressure increased from zero to its maximum value and （c） When the foundation pressure was kept constant （after the construction）. In this part a tentative method for calculating settlements of deeply embedded box foundations is also presented. The second part discusses the characteristics of the foundation pressure distribution and the method for computing pressure distribution is proposed.The last part presents the effects of temperature on the measurement of stress in reinforcements, and also the method for estimating stress in box foundations.