Tensile and shear strengths of concrete and rock
Abstract
Strength properties of concrete and rock materials may be assessed from process of deformation and the principal modes of fracture mechanics. This paper presents the experimental results obtained from two novel techniques of measuring mode I and mode II of concrete and rock strength: (1) Homogeneous Direct Tensile Test and (2) Direct Shear Test. The proposed testing arrangements are very simple, practical and reliable as well as rigorous from a mechanics viewpoint. They can both be used as routine tests. It provides simple means for evaluating strength properties of concrete, rock, ceramics, etc. under various conditions of loading (temperature, high confining pressure, immersed conditions) and even in hostile environments.
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Assessing water-induced changes in tensile behaviour of porous limestones by means of uniaxial direct pull test and indirect methods
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Dynamic behavior of concrete and cementitious materials
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Determining the tensile strength of concrete for wedge splitting specimens based on the fracture extreme theory
2020, Theoretical and Applied Fracture MechanicsTwo theoretical methods were developed to determine the tensile strength ft of concrete using wedge splitting specimens based on nil-stress intensity factor (nil-SIF) criterion and force equilibrium theory, respectively. With the fracture extreme theory (FET), only experimental peak load of one specimen was needed and did not require the measurement of critical crack mouth opening displacement CMODc for calculation. The existing experimental data were utilized to verify the two methods. Results show that the values of ft were insensitive to the initial notched ratios a0/D and agreed well with the experiment data. The influence of the size of the specimen was analyzed, ft was affected by the specimen size when the nil-SIF criterion was adopted. Nevertheless, ft calculated by the force equilibrium theory appeared to be kept a constant when the height of the specimen varied from 200 mm to 600 mm. Finally, the critical effective crack length ac and critical crack tip opening displacement CTODc were obtained and compared using the two methods.
Triaxial extension tests on sandstone using a simple auxiliary apparatus
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