Restoration of the bearing capacity of the pile foundation of the bridge to ensure its operational reliability

Abstract

The article presents a method for restoring the bearing capacity of pile foundations as one of the components of comprehensive monitoring of transport infrastructure facilities. It gives examples of systems for the technical condition monitoring of bridges, and outlines innovative approaches to strength monitoring. Using one of the piers of a railway bridge as an example, the latest technologies of survey and calculation of the pile foundation are applied. The testing laboratory performed work on the survey of the piles structure after completing the pile foundation construction for the bridge piers. The concrete continuity of piles and the presence of void pockets and decompaction in the concrete were to be determined. The bearing capacity of the pile footing was calculated and the design loads were determined. The study provides design models of the pile foundation, external loads, and the method statement. Hydrological conditions corresponded to those referred to in design documentation being part of the report on geological engineering surveys. The analysis of calculations revealed an increase in the sectional strength utilization rate in the “hollow” zone of the pile, taking into account the construction and further operation of the bridge, calling for special measures to strengthen the pile foundation. Then, the measures to restore the bearing capacity of the pile foundation and a brief description of the drill and inject technology are given. Upon completion of the drill and inject operations, the bearing capacity of the pile footing was calculated taking into account the stabilization of the soil mass and the pile strengthening. At the end of the study, the conclusion about the feasibility of the measures taken and on securing the bearing capacity and operational reliability of the bridge foundation piles is made.