Study On The Equivalent Strength Of RCC Induced By Different Shape Inducements

As we all now,in order to control the crack of temperature stress,the common method adopted at home and abroad is to set the crack director.Therefore,it is very important to master correctly the relevant knowledge of the equivalent strength of the crack directors,and to design rationally the shape,size and position of the inducer.The experimental research on crack director in China mainly focuses on the overall structural model test and the research on the crack directors and the calculation conditions.In practical engineering,RCC arch dam is often set up as unidirectional interval crack directors(penetrating crack director)and bidirectional interval crack directors(nonpenetrating crack director).At present,the equivalent crack analysis model is based on elliptic simplified analysis model.Depending on the National Natural Science Foundation project ?Equivalent Strength for Crack Director of High RCC Dam and Study of Optimal Layout?(50709013),based on the nonpenetrating crack director axial tensile test,this paper focuses on experimental study,the equivalent strength model of crack director,the finite element numerical simulation.In the experiment,the nonpenetrating crack director specimens with rectangular inducement and the nonpenetrating crack director specimens with elliptical inducement of 8 different sizes groups were compared and analyzed.The test results showed that the non penetrating crack director specimens' fracture was caused inside to out;when the rectangular inducer and the elliptical inducer at the same length of the axis,the equivalent strength value of the elliptical crack director specimens was slightly larger than that of the rectangular crack director specimens;got variation rules about equivalent strength with the crack director form and weaken level;and the value of equivalent strength of the crack director increased with the weaken level decreased;The relationship between the equivalent strength of the rectangular crack director and the equivalent strength of the elliptic crack director is derived.By using ABAQUS finite element calculation software,the 3D finite element model of axial tensile specimen was established based on the experimental data,and the damage process was simulated and analyzed.On the one hand,it verifies the correctness of the experimental results.On the other hand,using the advantage of finite element,combining with the stress contours and the strain of crack director around the development,the damaging of crack director in the axial tension test was judged,which make the research of equivalent strength of crack director was more perfect.In this paper,the influence coefficient formula of the crack director shape is applied to the calculation of the equivalent strength of the crack director of sha pai arch dam.By comparing the equivalent strength of the crack director in the example with the analysis results of other researchers,it proves that the formula of influence coefficient and the equivalent strength model of crack director have good applicability.The conclusions discussed in this paper has some referenced value for the study of crack director test,theoretical analysis and the design of crack director in practical engineering.