Combined test system for size effect of rock joint shear strength and its primary application research

被引：0

作者：

Du S. ^{[1
]}

Lyu Y. ^{[1
]}

Luo Z. ^{[2
]}

Huang M. ^{[3
]}

机构：

[1] Institute of Rock Mechanics, Ningbo University, Ningbo

[2] Institute of Geotechnical Engineering, Zhejiang University of Science and Technology, Hangzhou

[3] Department of Civil Engineering, Shaoxing University, Shaoxing

来源：

Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | 2021年 / 40卷 / 07期

基金：

中国国家自然科学基金;

关键词：

Equal precision; Rock joint; Rock mechanics; Shear strength; Size effect;

D O I：

10.13722/j.cnki.jrme.2020.1215

中图分类号：

学科分类号：

摘要：

The size effect of rock joint shear strength is a basic research issue in the field of rock mechanics and engineering geology. Due to the lack of mature direct shear test equipment on series size specimens at home and abroad, the research process on shear strength size effect of rock joints is slow. In this paper, a shear strength size effect direct shear combined test system of rock joints is developed, and the key technologies and methods are put forward such as fast conversion of multi-scale jointed specimens, classification of load measurement and control system, equivalence check of overlapping specimens, dynamic detection in testing process and shear loss measurement of structural planes, providing a basis experimental support platform for investigating the size effect of rock joint shear strength and other key scientific issues. The preliminary application results of the developed test system are demonstrated by two-level direct shear apparatus. It is shown that the test system can solve the problem of automatic transformation of specimens in the range of 100 times of the rock joint size from 10 cm×10 cm to 100 cm×100 cm, involving the process of transporting, positioning, loading and resetting of multi-scale specimens. The test system can also solve the problem of accuracy and stability of the measurement control system in the range of 500 times of the load from 2 kN to 1 000 kN. The accuracy level of the test system reaches 0.5 through the identification of a testing organization. The shear strength test results of overlapped specimens of 30 cm×30 cm and 40 cm×40 cm in two-level direct shear apparatus are compared, which shows that the convergence of the two sizes of samples is good. For the specimens with the same structural plane sizes under different loads, the peak values of the tangential load are related to the applied normal loads. For the specimens with different structural plane sizes under the same load, however, the ratio of the tangential load peak value to the normal load has a stable trend, except for a slight fluctuation in a certain size range of the structural plane. © 2021, Science Press. All right reserved.

引用

页码：1337 / 1349

页数：12

共 22 条

[1]

BIENIAWSKI Z T., Determining rock mass deformability: experience from case histories, International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, 15, 5, pp. 237-247, (1978)

[2]

HEUZE F E., Scale effects in the determination of rock mass strength and deformability, Rock Mechanics and Rock Engineering, 12, 3, pp. 167-192, (1980)

[3]

PINTO A, CUNHA D A., Scale effects in rock masses, pp. 77-103, (2020)

[4]

JING Hongwen, SU Haijian, YANG Dalin, Et al., Study of strength degradation law of damaged rock sample and its size effect, Chinese Journal of Rock Mechanics and Engineering, 31, 3, pp. 543-549, (2012)

[5]

ZHOU Huoming, SHENG Qian, WU Aiqing, Size effect analysis on macro-mecheanics parameters for the rock masses of the tgp shiplock slope, Chinese Journal of Rock Mechanics and Engineering, 20, 5, pp. 661-664, (2001)

[6]

BARTON N, CHOUBEY V., The shear strength of rock joints in theory and practice, Rock Mechanics, 10, pp. 1-54, (1997)

[7]

BANDIS S, LUMSDEN A C, BARTON N., Experimental studies of scales effects on the shear behaviour of rock joints, International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, 18, 1, pp. 1-21, (1981)

[8]

CASTELLI M, SAVIA S, ZANINETI A., Experimental evaluation of scale effect on the mechanical behavior of rock joints, Proceedings of International Eurock Symposium, pp. 205-210, (2001)

[9]

BARLA G, BARLA M, MARTINOTTI M E., Development of a new direct shear testing apparatus, Rock Mechanics and Rock Engineering, 43, pp. 117-122, (2010)

[10]

JIANG Y, XIAO J, TANABASHI Y, Et al., Development of an automated servo-controlled direct shear apparatus applying a constant normal stiffness condition, International Journal of Rock Mechanics and Mining Sciences, 41, 2, pp. 275-286, (2004)

← 1 2 3 →