In-situ testing of the shear strength of masonry joints – Proposal for a new Simplified testing approach and Comparison to existing techniques

Extensive in situ testing and undisturbed sampling were carried out near two steel piles to determine the long-term state of a clay in which these piles had been driven 7 years before. Results show that this material exhibits a rigidity that varies with the distance from the pile. The average rigidity in the zone of study is representative of a slightly destructured clay. The shear strength of this clay is, in most cases, equal to the shear strength of the intact material except in the zone located at depth greater than 3.5 m and within 30 cm of the pile wall, where lower shear strength values were consistently monitored. It is believed that reconsolidation after driving took place in this last case under relatively low stresses. Key words: piles, clays, ageing, destruction, reconsolidation, shear strength, rigidity, limit state.

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Pénétromètre à chute libre: Impact et pénétration dans des argiles reconstituées

Canadian Geotechnical Journal ◽

10.1139/t85-012 ◽

1985 ◽

Vol 22 (1) ◽

pp. 129-135 ◽

Cited By ~ 6

Author(s):

D. Levacher

Keyword(s):

Mechanical Properties ◽

Shear Strength ◽

Key Words ◽

Laboratory Tests ◽

Free Fall ◽

Test Series ◽

Dynamic Resistance ◽

In Situ Testing

The use of a free-fall penetrometer for the determination of the in situ mechanical properties of reconstituted clays is presented. The penetrometer is equipped with an accelerometer for measuring continuously the acceleration or the deceleration. The equipment is relatively simple and the test is fast. The usefulness of such a test is demonstrated, and its adaptation to in situ testing is easy to achieve. Laboratory tests indicate that the shear strength can be directly computed as a function of depth. The penetrometer, as developed, can reach a depth of 0.50 m, but it is possible to achieve greater depths with some modifications. The results presented pertain to a few test series on reconstituted clays, with impact velocities up to 8 m/s. Key words: penetrometer, impact, reconstituted clays, tests, dynamic resistance, cohesion. [Journal translation]

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Soil suitability estimation for housing purposes in landslide-prone areas. The case of Karya village, Patras, W. Greece

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.17072 ◽

2007 ◽

Vol 40 (4) ◽

pp. 1683

Author(s):

G. Koukis ◽

N. Sabatakakis ◽

S. Lainas

Keyword(s):

Shear Strength ◽

Slope Stability ◽

Limit Equilibrium ◽

Shear Strength Parameters ◽

In Situ Testing ◽

Strength Parameters ◽

Soil Suitability ◽

The City ◽

Heavy Rainfalls

This paper discusses a method of soil suitability estimation for housing purposes in landslide-prone areas based on engineering geological criteria. The studied places, Karya and Neo Souli villages are located on the eastern part of the city of Patras. Several instability problems were identified triggered by heavy rainfalls, especially during extreme meteorological events. The soil formations were classified in several geotechnical units while typical geotechnical profiles and slip sections were drawn. Limit equilibrium slope stability analyses were established in order to investigate the critical slide conditions, using shear strength parameters estimated from laboratory and in-situ testing. The studied area was finally divided into five zones according to the suitability of the encountered ground regarding housing purposes

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In-Situ Testing of Operation Stability in Hydraulic Turbine Generator Unit

Earth & Space 2008 ◽

10.1061/40988(323)67 ◽

2008 ◽

Cited By ~ 1

Author(s):

Shanshan Wang ◽

Pizhong Qiao

Keyword(s):

Hydraulic Turbine ◽

In Situ Testing ◽

Turbine Generator ◽

Operation Stability ◽

Generator Unit

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Test Methods for Mechanical Properties of Structural Adhesives

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.814 ◽

2010 ◽

Vol 97-101 ◽

pp. 814-817 ◽

Cited By ~ 1

Author(s):

Jun Deng

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Shear Strength ◽

Elastic Modulus ◽

Butt Joint ◽

Test Methods ◽

Joint Specimen ◽

Lap Shear ◽

Better Than

One of the greatest drawbacks to predicting the behaviour of bonded joints has been the lack of reliable data on the mechanical properties of adhesives. In this study, methods for determining mechanical properties of structural adhesive were discussed. The Young’s modulus, Poisson’s ratio and tensile strength of the adhesive were tested by dogbone specimens (bulk form) and butt joint specimens (in situ form). The shear modulus and shear strength were test by V-notched specimens (bulk form) and thick adherend lap-shear (TALS) joint specimens (in situ form). The test results show that the elastic modulus provided by the manufacturer is too low, the dogbone specimen is better than the butt joint specimen to test the tensile strength and elastic modulus and the TALS joint specimen is better than the V-notched specimen to test the shear strength.

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3C-SiC Nanowires In-Situ Modified Carbon/Carbon Composites and Their Effect on Mechanical and Thermal Properties

Nanomaterials ◽

10.3390/nano8110894 ◽

2018 ◽

Vol 8 (11) ◽

pp. 894 ◽

Cited By ~ 5

Author(s):

Hongjiao Lin ◽

Hejun Li ◽

Qingliang Shen ◽

Xiaohong Shi ◽

Tao Feng ◽

...

Keyword(s):

Shear Strength ◽

Thermal Properties ◽

Sol Gel ◽

Interlaminar Shear Strength ◽

Mechanical And Thermal Properties ◽

Initial Oxidation ◽

Sic Nanowires ◽

Out Of Plane ◽

Interlaminar Shear

An in-situ, catalyst-free method for synthesizing 3C-SiC ceramic nanowires (SiCNWs) inside carbon–carbon (C/C) composites was successfully achieved. Obtained samples in different stages were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman scattering spectroscopy. Results demonstrated that the combination of sol-gel impregnation and carbothermal reduction was an efficient method for in-situ SiCNW synthesis, inside C/C composites. Thermal properties and mechanical behaviors—including out-of-plane and in-plane compressive strengths, as well as interlaminar shear strength (ILLS) of SiCNW modified C/C composites—were investigated. By introducing SiCNWs, the initial oxidation temperature of C/C was increased remarkably. Meanwhile, out-of-plane and in-plane compressive strengths, as well as interlaminar shear strength (ILLS) of C/C composites were increased by 249.3%, 109.2%, and 190.0%, respectively. This significant improvement resulted from simultaneous reinforcement between the fiber/matrix (F/M) and matrix/matrix (M/M) interfaces, based on analysis of the fracture mechanism.

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