Experimental Research On Punching Shear Performance Of Recycled Concrete Two-way Slabs With Stud-Shear Reinforcement

Recent years, earthquakes and tsunamis occurred frequently, which has caused greatdamage to the houses, simultaneously produced large amounts of construction waste; Manybuildings built in the early years of new china have reached theirs’ basic life, need toreconstruct. When the old buildings and new constructions alternating, will also produce largeamounts of construction wastes; According to the statistics of relevant departments, wasteconcrete account for the most of these construction waste. Recycled concrete as a newbuilding material can recycle these waste concrete. This not only can reduce the amountof freestone, save natural resources, but also beautify the environment. The domestic andforeign research on the new building material were concentrated in the aspect of materialperformance, little study on the structure of recycled concrete. Whether the recycled concretecan be used in the practical projects or not, need further studies.This paper is on the basis of previous studies, researched the punching shear resistantperformance and the method to improve its punching shear performance of recycled concretetwo-way slabs. In the paper, 1 concrete slab and 11 recycled concrete slabs were designed.The 11 slabs include 1 reinforced recycled concrete slab and 10 recycled concrete slabs withstud-shear reinforcement(the 10 were divided into 5 species, two slabs in each). Through theconcentrated load which applied over the column in the middle of the slabs, we studied theeffect on punching shear capacity and ductility by the first row of stud-shear reinforcementfrom the edge of column and the spacing between stud-shear reinforcement. The mainresearch contents are as follow:(1) Through the test of punching shear capacity of recycled concrete two-way slabs withstud-shear reinforcement, this paper further study and analysis the whole process of punchingfailure, the deformation, the strain of bars and strain of recycled concrete two-way slabs withstud-shear reinforcement etc. Furthermore, combining with cracks’ development anddistribution of the slabs with stud-shear reinforcement, put forward the punching failuremechanism.(2) On the basis of the test, using the concrete failure criterion was derived from twinshear strength theory, according to the failure mode of the slabs, the shearing bearing capacityformula of the slabs with stud-shear reinforcement was given, which can provide calculationand analysis for the recycled concrete two-way slabs with stud-shear reinforcement used inthe practical engineering.(3) Established a non-linear finite element model of recycled concrete two-way slabswith stud-shear reinforcement, considered the slabs edges’ upturned, the bond slip betweenthe concrete damage plasticity and reinforcement, used the ABAQUS software to simulate thedeformation and bearing capacity of recycled concrete two-way slabs with stud-shearreinforcement, compared the results of the simulation with experimental results.Keywords: Stud-shear reinforcement, Recycled concrete, Two-way slabs, Punching shear...