中文摘要：

结合黄河小浪底排沙洞工程，对锚索张拉阶段的预应力效果和混凝土的徐变进行了探讨。通过建立合理的锚索张拉程序和数据采集制度，将混凝土的弹性应变、混凝土的徐变、预应力损失造成的应变从实测总应变中分离出来。分析结果显示：在预应力的张拉阶段，混凝土的徐变占总应变的24％。混凝土的徐变近似地与应力和持荷时间成线性关系，即ε=ασt，其中系数α与约束条件有关，不是一个常数。数据表明，通过实测数据得到混凝土衬砌中的应力与应力分布与有限元分析结果相一致。

英文摘要：

Using in-situ monitor data in flushingtunnel liner of Xiaolangdi reservoir, this paper studies the developments of concrete stress and concrete creep during its prestressing. By establishing a reasonable tensioning procedure and a specific data collecting system, the measured total strain can he decomposed into elastic strains, concrete creep and prestress loss-related strain. The results show that the concrete creep developed over the prestressing period accounts for roughly 24% of the total strain change. Concrete creep is proportional to the existing stress and the loading time t, and it can he expressed as ε = ασt with coefficient not a constant, but rather a constraint-dependent variable. This study also shows that the concrete stress and stress distribution calculated with a finite element method agree with the in-situ measurements.