Full-Scale Prefabrication and Non-Destructive Quality Monitoring of Novel Bridge Substructure for “Pile-Column Integration”

Abstract

The assembly process of “pile-column integration” is proposed in this study and applied in the engineering with the characteristics that most of the pile foundations are end-bearing piles, which is conducive to returning to the normal operation of transportation infrastructure in a timely manner. From the perspective of practical application, the bridge structure components, including pile column and cap beam, are reasonably designed and prefabricated according to the requirements of the reconstruction and expansion project of the old bridge. Through non-destructive testing technologies, the concrete strength, cover thickness of reinforcement, and component size of prefabricated components are monitored and tested to evaluate the quality of full-scale prefabricated bridge substructure for “pile-column integration”. The monitoring results showed that the concrete strength monitoring results of prefabricated components by the rebound method are relatively stable. The concrete strength of the prefabricated components was higher than the design concrete strength and their qualified rate was 100%. According to the monitoring of cover thickness of reinforcement, the measured cover thickness of reinforcement in prefabricated components by electromagnetic induction method fell within the allowable range, and their qualified rates were around 90%. The concrete strength and cover thickness of reinforcement for prefabricated components could meet the design requirements. Although the component size of the prefabricated components could be tested by a 3-D point cloud scanning system, the monitoring effect of a relatively smaller component size still needs to be improved. The quality monitoring of full-scale bridge substructures for “pile-column integration” proved the rationality of prefabrication and the feasibility of non-destructive testing technologies, providing references for the application of “pile-column integration”.