An Experimental Study on the Shear Characteristics of Typical Colluvial Soil with Gravel and the Stability of Slopes in

  • PDF / 9,232,217 Bytes
  • 20 Pages / 595.276 x 790.866 pts Page_size
  • 50 Downloads / 215 Views

DOWNLOAD

REPORT


ORIGINAL PAPER

An Experimental Study on the Shear Characteristics of Typical Colluvial Soil with Gravel and the Stability of Slopes in Wenzhou, China Zhouzhou Jin1 • Fuxue Sun1 • Yunhui Zhu2 Yue Yan1 • Yunguo Du3 • Gang Ge4



Liu Yang1



Baojiang Yu1



Received: 22 July 2020 / Accepted: 23 October 2020 Ó Indian Geotechnical Society 2020

Abstract Slope disasters are an important area of concern in the prevention and mitigation of national land disasters. To study the stability of the slope in Wenzhou, China, the basic physical and mechanical properties of undisturbed soil in this area were obtained from laboratory experiments of typical colluvial soil. From experimental results, it was determined that the soil was low-liquid limit clay containing gravel. The shear characteristics of soil for different water content, gravel ratios, and burial depth were also obtained from large-scale indoor direct shear tests. The test results show that: (1) for colluvial soil without gravel, increasing water content increases cohesion, but decreases internal friction angle; (2) for colluvial soil containing gravel, the shear stress drops sharply when the shear displacement is close to approximately 15 mm; (3) for the same gravel ratio, the contribution of the gravel to the shear strength of the shear surface is not significant at lower vertical stresses, but increases at higher vertical stresses. A finite element strength reduction method has been used to numerically simulate the typical binary slope in Wenzhou. The simulation results show that the factor of safety of the binary slope is dependent on the strength of the overlying

& Yunhui Zhu [email protected] 1

College of Civil Engineering and Architecture, Wenzhou University, Wenzhou 325035, Zhejiang, China

2

Oujiang College, Wenzhou University, No. 1, Landscape Avenue, Chashan Street, Higher Education Park, Ouhai District, Wenzhou 325035, Zhejiang, China

3

Wenzhou Mass Transit Railway Investment Group Co., Ltd., Wenzhou 325000, Zhejiang, China

4

Department of Shanghai Tunnel Engineering Co., Ltd., Shanghai 200000, China

soil. The variations of the safety factor with water content and the gravel ratio are consistent with the variations of shear strength with the water content and the gravel ratio obtained from the tests. Simultaneously, the soil–rock interface strength needs to be addressed in the analysis of binary slopes. Keywords Colluvial soil with gravel  Shear test  Water content  Gravel ratio  Shear strength  Factor of safety

Introduction With rising living standards and increased disaster awareness, the prevention and mitigation of disasters have become a key aspect of environmental and social governance. Within the field of disaster prevention and control, landslides have become important due to their characteristics of suddenness and largeness of scale [1]. From 1995 to 2003, more than 10,000 people were killed or reported missing due to landslides in China, along with economic losses of up to 57.5 billion yuan [2]. In August 2019, when Typhoon Le