Analysis of Load-Bearing Characteristics of Root Anchorage Foundation for a Suspension Bridge

Root anchorage formed by the rigid cap connecting the cluster root foundation, is a new type of anchor foundation of suspension bridge, which bears the load together through the interaction of cap, cluster root foundation and soil. As for the practical engineering of Qiupu River Bridge Root Anchorage Foundation, the numerical simulation method is used to analyze the overall displacement of Root Anchorage in two practical engineering conditions, the end of integral construction of anchorage (Case 1) and the operation stage of suspension bridge (Case 2).Besides, the stress characteristics of the group of Pile and Root Foundation are analyzed while the displacement characteristics of root anchorage are compared with the monitoring data. The results show that the horizontal and vertical displacement of anchorage under the load of main cable meets the requirements of similar suspension bridge anchorage displacement and the relevant regulations in domestic and abroad. In Case 1, under the eccentric load of the anchor body, the anchorage presents an overall backward state, and the vertical load is mainly borne by the pile caps and the cluster root foundation. In Case 2, under the action of the main cable force, the anchorage presents an overall forward state, and the overall horizontal displacement of the anchorage increases due to cable force. The vertical load is mainly borne by the pile platform (accounting for 33.37%) and the cluster root foundation (accounting for 66.63%), while the horizontal load is mainly borne by the cluster root foundation (accounting for 91.92%).