摘要
本文依据工程需要，采取淮河大堤老应段的原状和扰动土样，在室内对堤体及堤基土的剪切蠕变和拉伸蠕变特性进行了试验研究。粘土的蠕变剪切强度远低于瞬时剪切强度，Ｃ∞值仅是Ｃ值的４０％左右；相同含水条件下粘土的长时抗拉强度大于瞬时抗拉强度，长时拉伸应变量远大于瞬时拉伸应变量，约为２倍。运用土体的长期强度指标计算堤体受煤矿开采沉陷影响可能产生的拉张裂缝最大发育深度，并运用拉伸变量值作为控制指标，使用线式应变观测系统对堤体开裂破坏进行预测预报。
To meet the need for engineering project, the disturbed and undisturbed soil samples were taken from the Laoying part of Huaihe Dam and the characteristics of shear creep and tensile creep of soil from the dam body and its foundation were studied in laboratory. The creep shear strength (C ∞) of clay is far lower (about 40%) than the instantaneous shear strength (C); Under the condition of same moisture, the long term tensile strength of clay is larger than the instantaneous, and the long term strain is much larger (about 2 times) than the instantaneous. The maximum depth of tensile crack in dam influenced by coal miming settlement was calculated by using the long term strength indexes of soil mass and was controlled by tensile strain. The cracking damage of dam body is predicted from the data obtained by a linear strain observation system to safeguard the dam.
出处
《工程地质学报》
CSCD
1997年第1期53-58,共6页
Journal of Engineering Geology
关键词
土堤
剪切蠕变
拉伸蠕变
裂缝
强度
Earthfill dam, Shear creep, Tensile creep, Long term strength, Crack.
