Controlled displacement-rate in situ shear tests with pore pressure measurements

1985 ◽  
Vol 22 (1) ◽  
pp. 136-142 ◽  
Author(s):  
F. S. Shuri ◽  
D. D. Driscoll ◽  
S. J. Garner
Keyword(s):  
Shear Strength ◽  
Pore Pressure ◽  
Shear Zone ◽  
Large Scale ◽  
Bedding Plane ◽  
Western Canada ◽  
Shear Tests ◽  
Plane Shear ◽  
Clay Seam

Two large-scale in situ shear tests were conducted at a damsite in western Canada. The rock at the site is a Cretaceous shale containing a thin clay seam tentatively identified as a bedding-plane shear zone. The material in this seam is significantly weaker than the intact rock and influences the design of certain features of the dam and structures. In order to provide shear strength data for design, two large blocks of shale were sheared along the clay seam. These tests differed from conventional in situ shear tests in two significant ways: the rate of shear displacement was strictly controlled, and pore pressures (both positive and negative) in the shear zone were carefully monitored throughout the test. This note presents the material properties of the shear zone, describes the test equipment and techniques, and discusses the results obtained. Key words: shear strength, in situ testing, pore pressure, shale.

Determination of the Oldman River Dam foundation shear strength

1991 ◽  
Vol 28 (5) ◽  
pp. 698-707 ◽  
Author(s):  
M. M. Davachi ◽  
B. J. Sinclair ◽  
H. H. Hartmaier ◽  
B. L. Baggott ◽  
J. E. Peters
Keyword(s):  
Shear Strength ◽  
Large Diameter ◽  
Site Investigation ◽  
Bedding Plane ◽  
Plane Shear ◽  
Dam Foundation ◽  
Shearing Resistance ◽  
Oldman River

The paper describes the results of site investigation and laboratory testing and the analysis performed for the determination of foundation shear strength at the Oldman River Dam site in southwestern Alberta, Canada. Horizontally bedded claystones, siltstones, and sandstones at the site contain relatively weak bedding-plane shears that adversely affect foundation stability. Data on the bedding-plane shear characteristics were collected by mapping, borehole coring, shaft exploration, and large-diameter sampling. Shear planes of structure-wide continuity were identified. Numerous laboratory direct shear tests were done to measure in situ and residual shear strengths. The design angle of shearing resistance of selected continuous bedding-plane shears was evaluated by summing the representative residual angle of shearing resistance and components of the angle of shearing resistance due to in situ state, roughness, and thickness of the bedding-plane shears. Relatively flat dam slopes were found to be required for stability. The methods used at the Oldman River Dam should be applicable at other sites located in flat-lying mudrock sequences. Key words: Oldman River Dam, foundation shear strength, sedimentary rocks, bedding-plane shear, residual angle of shearing resistance, in situ state, roughness, thickness.

scholarly journals Basic Mechanical Parameter Relations of Soft Clay in Pearl River Delta

2014 ◽  
Vol 8 (1) ◽  
pp. 320-325 ◽  
Author(s):  
Zhangming Li ◽  
Na Qi ◽  
Zhibin Masumi ◽  
Weidi Lin
Keyword(s):  
Shear Strength ◽  
Pearl River Delta ◽  
Large Scale ◽  
Soft Clay ◽  
River Delta ◽  
Pearl River ◽  
Cylindrical Cavity Expansion ◽  
In Situ Data ◽  
The Pearl River

Basic parameters relations among CPT parameters, un-drained strength and other mechanical parameters of soft clay are presented based on an elastic-plastic solution for cylindrical cavity expansion for soil investigation in energy engineering. The relation between CPT parameters and shear strength from vane test is also presented based on the result. Thus, the CPT parameters can be determined directly by elastic parameters and shear strength or vane shear parameters and vice versa. That makes it possible to save the high test costs and provide theoretical formulas to avoid some tests which are limited due to the site and/or other condition. Results are compared between the relations and in situ data at a large-scale project in the Pearl River Delta. The results showed consistency between the relation and in situ data.

scholarly journals A Comparison between Interlaminar and In-plane Shear Strength of Unidirectional Glass Fibre-epoxy

1994 ◽  
Vol 3 (2) ◽  
pp. 096369359400300 ◽  
Author(s):  
Michael R. Wisnom ◽  
M. I. Jones
Keyword(s):  
Shear Strength ◽  
Cross Section ◽  
Glass Fibre ◽  
Shear Tests ◽  
Plane Shear ◽  
Short Beam ◽  
Unidirectional Glass ◽  
Beam Shear

Short beam shear tests have been carried out on square cross-section specimens cut from a 32 ply plate. By rotating the beams through 90° both interlaminar and in-plane strength can be measured with identical specimens. The in-plane shear strength was found to be at least 10% higher than the interlaminar strength.

Shear Strength of Sand–Clay Interfaces Through Large-Scale Direct Shear Tests

2020 ◽  
Vol 45 (5) ◽  
pp. 4343-4357
Author(s):  
Zhong-Liang Zhang ◽  
Zhen-Dong Cui ◽  
Ling-Zi Zhao
Keyword(s):  
Shear Strength ◽  
Large Scale ◽  
Direct Shear ◽  
Shear Tests ◽  
Direct Shear Tests

Shear Strength and Drainage Characteristics of Elastomeric Polyurethane Treated Coal-Fouled Ballast

2021 ◽  
pp. 036119812110363
Author(s):  
Syed Khaja Karimullah Hussaini ◽  
Dinesh Gundavaram
Keyword(s):  
Shear Strength ◽  
Large Scale ◽  
Empirical Relationship ◽  
Direct Shear ◽  
Shear Tests ◽  
Contamination Index ◽  
Direct Shear Tests ◽  
Fouled Ballast ◽  
Constant Head ◽  
Fouling Materials

The shear behavior and drainage characteristics of coal-fouled ballast when treated with elastomeric polyurethane are assessed by means of large-scale direct shear and permeability tests. The results from direct shear tests confirmed that the shear strength of both stabilized and unstabilized coal-fouled ballast was highly influenced by the extent of fouling (VCI: void contamination index). The performance index (PI) of elastomer-stabilized coal-fouled ballast (ESFB), determined as the fraction of shear strength of fouled ballast to the shear strength of fresh and unstabilized ballast, lies in the range of 1.23 to 0.84. Moreover, the performance of ESFB having VCI ≥30% was found to be either similar to or poorer than that of clean ballast without any treatment, thus indicating that the elastomer treatment may be provided only to ballast with VCI ≤30%. The results from constant head permeability tests indicate that the hydraulic conductivity of ballast ( k) is highly influenced by the presence of fouling materials but is only slightly reduced as a result of the elastomer stabilization. The k of ballast decreased from 43 to 0.18 mm/s as the VCI increased from 0 to 75%. For VCI ≥ 45% the k of ballast was found to be lower than that recommended for sub-ballast. On the other hand, the k of ballast reduced slightly from 43 to 37 mm/s because of the elastomer stabilization. Furthermore, an empirical relationship is established between k and e to determine the k of both stabilized and unstabilized fouled ballast.

In Situ Shear Tests on Masonry Panels Strengthened with Fiber-Reinforced Mortar Repointing

2017 ◽  
Vol 747 ◽  
pp. 282-288
Author(s):  
Nicola Cavalagli ◽  
Massimiliano Gioffrè ◽  
Vittorio Gusella ◽  
Chiara Pepi ◽  
Bernie Baietti ◽  
...  
Keyword(s):  
Shear Strength ◽  
Local Information ◽  
Fiber Reinforced ◽  
Compression Tests ◽  
Shear Tests ◽  
In Situ Tests ◽  
Joint Shear Strength ◽  
Reinforced Masonry ◽  
Diagonal Compression

In this paper the effect of joints structural repointing on single-wythe brickwork masonry using a fiber-reinforced mortar is investigated. Changes in shear strength are evaluated by in-situ tests carried out both on unreinforced and reinforced masonry specimens. The masonry joint shear strength, according to the standard ASTM C 1513, gives local information, while diagonal compression tests provides information on the global masonry shear response. The comparison highlights a good performance in both local and global masonry response, where the shear strength increases.

In situ shear tests of soil blocks with roots

1998 ◽  
Vol 35 (4) ◽  
pp. 579-590 ◽  
Author(s):  
Tien H Wu ◽  
Alex Watson
Keyword(s):  
Shear Strength ◽  
Root System ◽  
Tensile Force ◽  
Failure Surface ◽  
Soil Reinforcement ◽  
Shear Tests ◽  
Maximum Displacement ◽  
Shearing Resistance ◽  
Simplified Procedures

In situ shear tests were performed on soil blocks that contained roots to study the contribution of roots to the shear strength in a case where the shear deformation is not constrained to a thin zone. The shearing resistance of the soil-root system, the tensile force in selected roots, and the deformation of the soil block were measured. The roots were exposed after the test and their positions were determined and used to estimate the initial positions. The root force and the shearing resistance of the soil-root system were estimated with known solutions and compared with measured root force and shearing resistance. None of the roots that passed through the shear zone failed in tension at the maximum displacement. As a consequence, the root resistance is much less than that found in a case where the failure surface is restricted to the boundary between a weak soil and a firm base and where roots are anchored in the firm base and fail in tension. Simplified procedures for estimating root forces are suggested for the case of a thick shear zone.Key words: in situ test, roots, shear strength, slope stability, soil reinforcement, soil–root interaction.

Sign in / Sign up

Export Citation Format

Share Document