Behavior of polyurea-woven glass fiber mesh composite reinforced RC slabs under contact explosion

Pure polyurea (PU) coating has hidden danger in covering blast fragments and reducing structural local damage when blast-induced perforation occurs in the structure. Thus, enhancement method of adding woven glass fiber mesh (WGF) into pure PU coating to form PU-WGF composite coating was proposed. Field explosion tests on normal RC slab, PU reinforced RC slab and PU-WGF reinforced RC slab were carried out to comparatively study the reinforcing performance between PU coating and PU-WGF coating. Simultaneously, contact explosion tests were also conducted on PU-woven carbon fiber mesh composite (PU-WCF) reinforced RC slab to verify the enhancement of other types of woven fiber mesh on pure PU matrix. Finally, the experimental results were used to calibrate the numerical calculation model of the PU-WGF reinforced RC slab. Failure mode of coating, blast fragment distribution and damage extent of RC slab were investigated. Results show that the WGF can enhance the load transmitting, integrity and fracture resistance of the PU coating, and change the failure mode of PU coating from shear punching failure to tensile failure.