Experimental Study On The Resistance Of Concrete Under Dynamic And Static Loads

Concrete is widely used in construction engineering,hydraulic engineering,military fortifications and road works.The safety of concrete structures was severely tested when the structures were subjected to seismic loads or collapsed by major fires,military installations were bombarded and civil structures exploded.At present,the anti-destructive performance of concrete under different loads is mainly based on qualitative judgment,and it is not based on a certain method to quantitatively describe the anti-destructive level of concrete under different load.Therefore,it is necessary to study the destructive resistance of concrete with different strength grades under different loads,which is very important to evaluate the safety of concrete structures and how to use concrete materials economically.In this paper,the mechanical properties of C25,C35,C45 concrete under dynamic and static load are studied.The safety of concrete with different strength grade under static load and different dynamic load(impact and blasting load)is characterized by the experimental data.The influence of strength grade on the destructive resistance of concrete under different loads is quantitatively analyzed.The main research contents are as follows:1)The mechanical parameters of concrete with different strength grades were obtained by static pressure experiment,and the destructive resistance of concrete with different strength grade was characterized by quantitative analysis.2)The dynamic mechanical parameters of concrete specimens with different strength grades were obtained by SHPB experiment,and the destructive resistance of concrete with different strength grade was characterized by quantitative analysis.The results were analyzed by numerical simulation.Contrast with laboratory experiments.3)The damage degree of concrete blocks with different strength grades was characterized by G-G-S distribution regression analysis,and the damage resistance was quantitatively analyzed.The experimental results were analyzed by numerical simulation.The main research results are as follows:In this paper,the experimental data of indoor and outdoor experiments were used to quantitatively characterize the destructive resistance of concrete with different strength grades.The parameters such as static maximum compressive strength,dynamic maximum compressive strength and fractal dimension were able to reasonably resist the destructive strength of concrete.The results show that the stress and strain curves of concrete with different strength grades are analyzed by simulating SHPB experiment.It is found that the maximum stress of C25,C35 and C45 is increased to about 2 times of its own strength,and its anti-destructive increase is not The results show that C35 and C45 are 25.7%and 60.6%higher than those of C25 concrete under blasting load.