(1 广州市设计院集团有限公司, 广州 510620; 2 广州建筑股份有限公司, 广州 510030;3 广州市建筑集团有限公司, 广州 510030; 4 广州大学土木工程学院, 广州 510006)

摘要: 降雨诱发滑坡是花岗岩残积土地区主要地质灾害之一。 为研究花岗岩残积土边坡在强降雨条件下的响应,在广州市黄埔区选取了一典型非饱和花岗岩残积土边坡开展系列研究,包括现场雨量监测、固结不排水三轴试验、滤纸法试验。 基于监测数据与试验结果,研究风化程度对抗剪强度及土-水特征曲线的影响规律,探究了当地不同降雨工况对现场边坡稳定的影响。 结果表明,随着风化程度加剧花岗岩残积土有效抗剪强度指标均有不同程度的减小,其中,风化差异导致的有效内摩擦角变化幅度小于有效黏聚力变化幅度;风化程度差异也影响花岗岩残积土的非饱和水力特性;降雨强度与边坡安全系数的降幅呈正相关关系,而降雨历时与边坡安全系数的恢复速度呈负相关关系。 该研究可为典型花岗岩残积土边坡相关工程的科学设计与灾变防控提供一定借鉴。

关键词: 花岗岩残积土; 三轴试验; 滤纸法; 强降雨; 边坡稳定性; 岩土风化

中图分类号:TU398. 7 文献标志码:A 文章编号:1002-848X(2022)24-0138-06

DOI:10. 19701 / j. jzjg. ZJ220082

Study on unsaturated characteristics of granite residual soil and its slope stability

HUANG Junguang1,2,3, FAN Peiyan4, SHAN Yi4, LI Weike1,2,3, LI Lei1,2,3,4

(1 Guangzhou Design Institute Group Co. , Ltd. , Guangzhou 510620, China; 2 Guangzhou Construction Co. , Ltd. ,Guangzhou 510030, China; 3 Guangzhou Construction Group Co. , Ltd. , Guangzhou 510030, China; 4 School ofCivil Engineering, Guangzhou University, Guangzhou 510006, China)

Abstract: Rainfall-induced landslide is one of the significant geological hazards in granite residual soil areas. Toinvestigate the response of the granite residual soil slope to torrential rain, a series of studies which include in-situ rainfallmonitoring, consolidated undrained triaxial tests and filter paper method were conducted on a typical unsaturated graniteresidual soil slope located in Huangpu, Guangzhou. Based on the monitoring data and tests results, the influence law ofweathering degree on shear strength and soil-water characteristic curve was studied, and the effect of different local rainfallconditions on the site slope stability was gave insights into. The results show that as the weathering increases, the effectiveshear strength parameters of the granite residual soils decrease in different degrees, and the change range of effectiveinternal friction angle caused by weathering difference is smaller than that of effective cohesion. The unsaturated hydraulicproperties of granite residual soils are also affected by weathering difference. The decrease of slope safety factor is positivelycorrelated with the rainfall intensity, while the recovery rate of slope safety factor is negatively correlated with the rainfallduration. This study can provide some reference for scientific design and disaster prevention and control of typical graniteresidual soil slope related projects.

Keywords:granite residual soil; triaxial testing; filter paper method; torrential rain; slope stability; weathering of rock andsoil

∗国家自然科学基金(52008121),中国博士后科学基金(2020M682652),住房和城乡建设部科学技术计划项目(2022-K-039),广东省住房和城乡建设厅科技计划项目( 2020-K5-144658),广州市建筑集团有限公司科技计划项目( 2021-KJ013、2021-KJ039)。

第一作者:黄俊光,硕士,教授级高级工程师,注册土木工程师(岩土),主要从事岩土工程设计工作,Email:hj020@ 126. com。

[引用本文] 黄俊光,范培彦,单毅,等. 花岗岩残积土非饱和特性及其边坡稳定性研究[ J]. 建筑结构,2022,52(24):138-143. HUANG Junguang, FAN Peiyan, SHAN Yi,et al. Study on unsaturated characteristics of granite residualsoil and its slope stability[J]. Building Structure,2022,52(24):138-143.