Sichuan-Tibet 318 Diversion Project

Background

The project is part of the reconstruction of National Highway 318, specifically the section passing through Yajiang County. It involves the construction of a bridge spanning the Yalong River, named the "Yalong River Bridge." The bridge piers are approximately 70 meters in height. The construction method for the bridge involves cast-in-place beams, using a pumping process for concrete delivery. (Fig. 1).

Fig. 1 Schematic diagram of the site

Project challenge

The issue of appearance of bubble and compatibility

The construction part of the project is a cast-in-place beam, and the on-site pumping process is difficult to carry out. After a long pumping process through the pump pipes, the concrete experiences significant pumping loss and an increase in air content. Additionally, the overall workability of the concrete is relatively poor.