南京长江二桥南汊桥塔基主要工程地质问题与力学参数的确定

南京长江二桥南汊桥塔基主要工程地质问题是岩石的强度问题。由于塔基岩石为胶结差的砾岩与砂砾岩，且结构和颗粒不均匀，勘探中取样极为困难，加之岩石常规试验的不适宜性，使得岩石力学强度问题复杂化。为此勘察期间对塔基岩石工程地质特性进行了较全面的研究，并结合类似岩石的原位试验对比分析，确定了符合本大桥的力学参数建议值，为桩基的优化设计提供了可靠依据。

MAIN PROBLEMS AND DETERMINATION OF FOUNDATION STRENGTH OF PIER OF THE SECOND NANJING BRIDGE

The rock strength is one of the main problems related to the pier foundation of the second Nanjing bridge across the Changjiang River. Poor cementation of conglomerate with sandy conglomerate and wide range of gravel diameters make it difficult to sample and to test by the conventional methods. A thorough geological investigation having been carried out and field tests conducted some mechanical parameters are suggested in this paper. Our work has provided a dependable basis for optimization design of the bridge piers.