Performance of North Anchorage Excavation of Fuma Yangtze River Bridge in Wanzhou, China

Abstract

To ensure the safety of constructing the north anchorage excavation of Fuma Yangtze River Bridge, an extensive instrumentation program was carried out to monitor the performance of the excavation. This monitoring effort included the ground movements of soil outside the excavation zone, ground movements of the tops of piles, lateral deflections of piles, and prestress in cables. Based on an analysis of the monitoring data, the following findings were obtained: shallow landslides were induced by rainfall at several locations outside the excavation zone, and the movement directions of soil were consistent with the natural terrain. The horizontal displacements of the west and east top beams were generally larger than that of the north side. The vertical movements of the tops of the piles exhibited heave initially and then transitioned into settlement. The deflected profiles of the piles were similar, and the maximum lateral pile deflections were very close. The measured deformations and internal forces of the support system did not exceed the alarm values, which suggested that the excavation was in a stable state.