Research And Test On Bearing Capacity Of Deep Water Large Diameter Pile In Over-thick Sand Gravel Layer

Currently, sea and river-crossing bridge engineering developing rapidly,involving deep large diameter pile foundation engineering is increasing. Becauseconstruction technical difficulties, complex process, quality control and test pile isparticularly important. Conventional static load test time-consuming, laborious anddemanding on the test site, but since the new method of balancing test has beenwidely promoted.The bridge site of XiangYang Han River Bridge is very complex geologicalenvironment. Its maximum depth of8.5m, the minimum thickness of the gravel layer30m, pebble size3~25cm, which gives foundation construction project has broughtgreat challenges. For such a complex geological conditions, pile constructiontechnology choice is smooth or not bridge foundation construction deepwaterprerequisite pile construction quality control is the key factor.This article first of several pile testing methods were compared and analyzed,introduces static load method, self-balancing method, dynamic pile testing method,static and dynamic testing of piles law principles, capacity to determine theadvantages and disadvantages. Then with engineering examples, elaborated from thebalance test equipment, testing procedures and through two methods Calculatingultimate bearing capacity of the specific process.By summarizing self-balancing testpile ultimate bearing capacity factors analysis of numerical simulation results,combined with experimental conclusions arrived at a different process conditions intothe hole on the ultimate bearing capacity of importance. For the smoothimplementation of the project to provide a reliable theoretical basis.Through theengineering practice in the constant research and exploration, the smooth realizationof the super thick gravel layer of bridge foundation construction quality goal and thegoal of the project, but also for the project to create a certain economic benefit.