| Fracture mechanics is a subject, which researches crack extension regularity about the object with crack under the load. For ideal elasticity medium structure with crack or law, stress singularity distribution consists in the crack tip. Stress intensity factor can indicate effectively stress field intensity nearby crack tip. Because brittle material is easy to fracture, concrete and ceramics are studied through the fracture theory in the paper. Fracture process and bearing capacity ceramics are analyzed by strain gauge tracking electric measurement experiment. The following work is studied in the paper:(1) Wedge-splitting experiment of 4 sizes of steel fiber reinforced concrete specimens were carried out, in which two specimens were measured with electrical strain gauges equipment. The bearing capacity and crack open displacement are obtained(2) Axial tension experiments were carried out for 5 specimens with or without impregnating compounds, 8 specimens was tested by beams' four-point bending experiments, and one specimen was stick with strain gauges for tracking the failure process. The axial force and shear stress were obtained.(3) Analytic solution about crack open displacement can be obtained. The theory is used on the concrete material, and the analytic solution is compared with experimental results. Also cohesive stress with the displacement is investigated.(4) Numerical simulation about concrete with crack was carried through ANSYS finite element software, and the stress intensity factor is compared with the calculated value. The ux, uy and equivalent stress are received.(5) 7 coarse porcelain beam specimens and 4 fine porcelain specimens with different notch were tested by the beams' three-point bending load. A series of curves of load-displacement were obtained about each specimen; the stress intensity factors were calculated.
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