Numerical Analysis on Utilization of Soft Rock in Siping Concrete Faced Rockfill Dam

摘要

In modern concrete faced dam technology,soft rock has been increasingly utilized as filling material to save construction time and cost.Soft rock has relatively lower strength and modulus compared to hard rock. The possible risk induced by using soft rock stuff is the larger dam body deformation which may lead to the concrete face cracking.So it is generally needed to take special research to verify the safety and feasibility of soft rock utilization before construction. The Siping dam,a concrete faced rockfill dam with a height of 90.5 m,has just been built in Hubei Province,China.In this dam,sand gravel was used as the main filling material,and weathered shale (soft rock) was taken as secondary material.Because sand gravel was not easy to collect from river bed at flood season,it was therefore hoped to make use of weathered shale as much as possible with its rich resource and mining convenience. to examine the stress and strain situations at different levels of soft rock u-tilization in Siping dam filling,numerical simulation analysis was conducted.Based on the numerical work and comparison with some existing dams,the optimized zoning scheme for sufficient use of soft rock was proved feasible and acceptable,in which the stress and strain of the dam should be in good conditions. The optimized zoning scheme was actually applied to construction.