Dynamic Behavior Of CTRC And ECC Layered Reinforced Concrete Material Under Impact Load

Fiber can enhance the properties of cement based materials.The effect of different fibers on the strengthening and improving effect of cement matrix is quite different.The effect of high elastic modulus fiber on cement-based materials is more about increasing strength,the effect of low elastic modulus fibers on cement-based materials is toughening and cracking resistance.Compared with one type of fiber reinforced cementitious materials,the performance of hybrid fiber reinforced cementitious materials has remarkable improvement.But the ingredient and composition of the matrix is not the same in different fiber reinforced cementitious materials.By analyzing the advantages and disadvantages of different fiber reinforced cementitious material,this paper made engineered cementitious composites(ECC)and carbon textile reinforced concrete(CTRC)composite the CTRC and ECC layered reinforced concrete by layer pouring to take full advantage of the two materials and realize advantageous complementarities.Based on the different impact surfaces and layer thickness,the test cases were established.In this paper,devices such as press test machine and split Hopkinson pressure bar(SHPB)were used to carry out series tests(loading rate ranging from quasi—static to dynamic impact)for CTRC and ECC layered reinforced concrete.This paper was organized by mainly focusing on the following aspects:(1)Quasi-static uniaxial compressive properties of CTRC and ECC layered reinforced concrete with different layer thickness were researched.This paper explored and compared the influences of layer thickness on some the failure mode and the compressive strength of CTRC and ECC layered reinforced concrete.(2)Dynamic impact properties of CTRC and ECC layered reinforced concrete with different layer thickness and impacted surface were experimentally studied by SHPB system.These works analyzed the layer thickness and impacted surface material on change rule of impact stress-strain curve and several mechanical parameters of CTRC and ECC layered reinforced concrete such as failure pattern,peak strength,peak strain,dynamic increase factor(DIF)and impact toughness.Comparative analyses were also conducted for CTRC and ECC layered reinforced concrete under quasi static loading and dynamic loading.(3)The mechanical properties of the CTRC(S)and ECC layered reinforced concrete which CTRC layer mixed with steel fiber from quasi-static to dynamic impact were tested.(4)The differences and similarities of impact mechanical properties of CTRC(S)and ECC layered reinforced concrete and CTRC(S)and ECC layered reinforced concrete are compared and analyzed,and the reasons are explained from the fundamental mechanism.