Experimental Research On RC Beams Strengthened With NSM Spiral Rib Wires Under Different Prestress Levels

At present, China has entered a new era than new construction and maintenance oftransformation of both, and it will shift the focus of the existing building renovation,maintenance, reinforcement. The low standards of building construction which was builtin the past after a period of time after use can not meet the current economic changesbrought about by the development and new demand usage, it needs to repair,reinforcement and modernization.It is a new reinforcement method that built-in pre-stressed helix rib steel reinforcedconcrete structures. Compared with the traditional embedded CFRP reinforcementmethod, it uses low relaxation wire as reinforcement material, not only cheap, but alsohas good ductility, adhesion.This article related tests carried out its research and theoretical analysis. The mainobject of study and conclusions are as follows:1. First, we systematic summary of research in related fields at home and abroad,reviewed the material reinforcement bars embedded in the structure of the level ofResearch and Development, has discussed the advantages and limitations of research.2. Introduced to impose the maximum tension stress control formula; wereembedded in reinforced concrete beams pre-stress reinforcement material crackingcapacity before and after the cross-section analysis, are given a reasonable cross-sectionreinforced concrete beams bearing capacity formula.3. Based on eight concrete beams bending properties of static load test study, theflexural capacity of reinforced concrete beams, deformation and cracks, etc. to carry outa more systematic study. The results show that the embedded pre-stressed spiral rib steelreinforced concrete beams were able to significantly improve the bearing capacity ofreinforced concrete beams and reinforced concrete beams reinforced with the crackingload increased the amount of rate increases, but the yield load and ultimate load to twotendons need to be considered material synergies; the reinforcement method of delayingthe beam to carry out the cracks, reducing the maximum crack beam, the beamdeformation resistance increased so obvious effect.4. Based on ordinary reinforced concrete beam cracks and deformation theory, thebuilt-in reinforced concrete beams pre-stressed reinforcement material deformation and crack development were analyzed. The results show that improving the characteristicsof reinforced concrete beams in the load, crack control, deflection and other significantrole.