Analysis Of Factor Influence On SHPB Impact Performance Of Lightweight Aggregate Concrete With Anti-explosive Coating

Lightweight aggregate concrete?LWAC?has gradually become a direction for the development of modern civil engineering materials due to its light weight and low cost.However,due to its brittleness,the structure is easily damaged when subjected to power shock.Replacing part of lightweight aggregate with conventional aggregate,adding fiber or coating anti-explosive coating?SPUA-BR?can increase its ductility to some extent and improve its impact resistance.In order to investigate the effects of aggregate,fiber and SPUA-BR on the dynamic impact properties of lightweight aggregate concrete,a series of dynamic impact tests were carried out using a split Hopkinson Pressure Bar?SHPB?device.The content is as follows:?1?Static mechanical tests on fiber reinforced LWAC?FRLWCs?were carried out to analyze the reinforcing effects of different fibers on various static indexes of lightweight aggregate concrete;?2?By carrying out SHPB impact tests on different types of LWAC and FRLWCs,it is found that the kinetic parameters of mixed light concrete?HALWC?are higher than that of sand light concrete?SLWC?;the incorporation of fibers can reduce the damage degree of LWAC.Different fibers have different dynamic peak stress,peak strain and energy consumption,and both have obvious strain rate effects;?3?Comprehensive analysis of the results of the LWAC impact test of SPUA-BR shows that the dynamic peak stress of LWAC increases linearly with the increase of coating thickNess,and the dynamic peak strain decreases linearly with the increase of coating thickNess,and has strain.Rate effect;When the FRWLCs coated with 2 mm SPUA-BR was subjected to multiple impacts at different strain rates,the peak stress and dynamic elastic mode decreased with the increase of the number of impacts;?4?The effect of SPUA-BR thickness,strain rate and impact frequency on energy consumption was analyzed from the energy point of view.It was found that the energy attenuation index of the coating was quadratic with the coating thickNess;the specific energy absorption with the strain rate Increase and increase,decrease with the increase of the number of impacts,and there is a critical strain rate with zero energy absorption,which is about 51.73 s^-1;?5?Based on the improved ZWT constitutive model,the Weibull probability damage variable is introduced to construct a dynamic damage constitutive model suitable for lightweight aggregate concrete properties.