中文摘要：

小浪底排沙洞是我国首例采用无粘结环锚预应力混凝土衬砌的水工隧洞,本文根据运行期间混凝土应变计所获得的大量实测数据,对3#排沙洞ST3-B段衬砌混凝土运行的应力状态进行了分析评价。结果表明,运行期衬砌混凝土自生体积变形持续增长,到2003年8月基本趋于稳定;混凝土的徐变发展在运行期基本保持稳定;当运行水位为最高水位时,所有混凝土应变计所在位置的混凝土应力均为压应力。分析结果认为,ST3-B观测段在最高运行水位也不会产生能够引起裂缝的拉应力,不会出现开裂和渗漏,能够保证正常使用,小浪底排沙洞处于安全运行状态。以期对无粘结环锚预应力混凝土衬砌的安全评价提供指导意义,为今后类似工程的设计提供重要的参考数据。

英文摘要：

Xiaolangdi sediment flushing tunnels are the first waterway with unbonded circumferential pre-stressed lining in China. This paper analyzes and evaluates the stress state of lining concrete in the ST3-B segment of sediment flushing ttmnel No. 3, based on a large number of data collected by concrete strain gauges over operation periods. The results show that autogenous volume deformation of concrete was growing continuously during operation period and tended to be steady after August 2003 while concrete creep was developing gradually. At the stage of the highest operation water level, all the concrete stresses recorded by the gauges were compressive and neither cracks nor leakage developed, which ensures the safety during operation of the tunnels. This work would provide a guide to safety evaluation on unbonded circumferential pre-stressed lining and useful data for design of similar tunnels.