PROBLEMS IN RECONSTRUCTION OF PILE-RAFT FOUNDATION

Abstract

In practice, in many cases using combination of piles and large-slabs could be observed technological and structural defects before the start of their operation. These defects are dictated by the complex interaction between piles system and thin raft slabs. In order to establish the causes of defects can be imposed a wide range of studies covering research on the ground, the reinforced concrete structural elements and materials (piles and raft), the technology performance and others. In this study in order to identify the causes of defects are used a series of research methods for determining the properties of materials, environmental conditions and computational models to describe the interaction between ground and upper structure. With this set of methods are established causes and selected measures for appropriate reconstruction. The scope of these measures consists in the use of a combination of hardening by injection of the ground under the contact base of raft. With grouting the aims are to improve the skin friction and end bearing resistance of the piles. In the complex decision are sought the approaches to keep the completed structures-piles and raft. The focus of this work is to improve the interaction of the pile-raft system and ground base at the expense of reducing the load on piles. In this case, the geological formation, represented by Paleogene sediments with alternating layers of hard clay and clay sandstones largely supports the realization of the design measures.