混凝土坝廊道真实应力影响因素分析

为了进行混凝土坝设计施工阶段廊道应力的计算,避免廊道裂缝的产生,应用SAPTIS程序对施工期廊道在不同影响因素下的应力进行计算,包括不同基础约束情况、环境气温情况、不同坝体冷却方式。结果表明,陡坡坝段的廊道应力远大于河床坝段的应力,地基弹模的改变对于陡坡廊道和河床廊道的应力影响程度基本相同;环境气温对于廊道应力有较大的影响,环境温度越高,廊道应力越小;在降温温差相同情况下,不同降温过程对二冷末廊道最大应力没有影响,仅影响局部应力发展过程,降温越早,相应的应力越大。

Analysis on factor of influence from real stress of gallery in concrete dam

In order to calculate the stress of gallery during the design and construction phases of concrete dam and avoid the occurrences of cracks of gallery，the stresses of gallery under various influencing factors，including various foundation constraints，environmental temperatures and different dam body cooling modes during construction phase are calculated with the software program———SAPTIS. The result shows that the stress of the gallery in the dam section with steep slope is far larger than that in the riverbed dam section，while the degree of the influence from the change of the foundation elastic modulus on both the stresses of the gallery in the dam section with steep slope and the river bed dam section is basically the same. The influence from environmental temperature on the stress of gallery is larger，that is to say，the higher the environmental temperature is，the stress of gallery is to be smaller. In the same case of the same temperature-drop difference，there are no any influences from different temperature-drop processes on the maximum stress of gallery at the end of the secondary cooling，which only influence the development process of local stress，i. e. the earlier the temperature-drop is，the corresponding stress is to be larger.