渗透固结作用下黏土坝基的时效变形和安全加固  

Time Deformation and Safety Reinforcement of Clay Dam Foundation Based on Seepage and Consolidation

作　　者：王军[1] 曹平[2] 赵延林[3] 邹洪波[1] 罗章[1] 

机构地区：[1]湖南工程学院建筑工程学院 [2]中南大学资源与安全工程学院 [3]湖南科技大学能源与安全工程学院

出　　处：《中国安全科学学报》2013年第6期116-121,共6页China Safety Science Journal

基　　金：国家自然科学基金资助(10972238;51274097);湖南省教育厅科研资助项目(13B016;12C0635)

摘　　要：为了研究渗流、固结、蠕变作用下水泥土防渗与加固黏土坝基的时效稳定和安全加固,采用Mohr-Coulomb准则和单向固结理论,提出改进的非线性西原蠕变模型和耦合控制方程。结合算例,用改编的差分程序,得出黏土坝基的垂直位移和孔压分布曲线。结果表明:在仅考虑固结效应的情况下,坝体的竖向位移最小,为7 cm,分布在坝顶局部;在考虑渗透、蠕变效应的情况下,竖向位移最大,为16 cm,分布在坝脚和铺盖范围,且随时间的延续位移不断增大。并得出耦合条件下坝体结构特征点的孔压分布:在坝基的中上部、坝身的坡脚、铺盖与坝基接触的局部范围孔压变化最大,且负孔压增大区与最大竖向位移区域叠合,是坝基防渗与加固的重点范围。Fro the sake of studying the time stability and safety reinforcement of clay dam foundation, a modified Saihara creep model was built using Mohr-Coulomb field rule and an unidirection theory. A cou- pling equation was established, which reflects the effects of factors, such as consolidation and creep, on the seepage of clay dam foundation. An example was used to research the distribution of vertical displacement and pore pressure throughout the whole dam structure. The results show that the minimum vertical displace- ment is presented with the minimum value 7 cm in the condition of consolidation influence and the maxi- mum vertical displacement is 16 cm for the coupling effect on seepage and creep, which is increasing with the time going. The remarkable scope lies in the places including middle-top position of dam foundation, slope footstep position of dam upside structure and interface region between bespread and dam foundation, which is involved by the program calculation on the vertical displacement and pore pressure changment, Simultaneously the inosculation phenomenon is discovered in the above scope between vertical displace- ment and pore pressure. Lastly, the key treated scope is abtained by the instance. So the influence of seep- age-consolidation-creep cannot be ignored in engineering construction and theoritical research on the prob- lems of cutoff , reinforcement and stability of clay dam foundation.

关 键 词：黏土坝基 渗透 固结 蠕变 时效稳定性 安全加固 

分 类 号：X959[环境科学与工程—安全科学]