Experimental Research On Concrete Columns Reinforced With Prefabricated Cage System Under Axial Compression

Prefabricated cage system for reinforcing concrete members is a newreinforcement to reinforce concrete members。The fabrication of prefabricatedcage system is similar to rebar reinforced system，using prefabricated cageinstead of rebar cage。Longitudinal steel and transverse steel are connectedmonolithically and work together。Prefabricated cage system can be used tomany members of concrete structure just like beams、slabs、columns、shearwalls、foundations and so on。Prefabricated cage system can be used not onlyto build a whole building but also to be a member part of a building。Prefabricated cage system not only have the advantage of rebar reinforcedsystem，but also have its own advantage：it can more effectively confine theconcrete，increasing the ductility and the capacity of absorbing energy；it canbe build fast and have good construction quality。Prefabricated cage system was invented by Mohanmmad Shamsai and HalilSezen fist in2005at the Ohio state university of the United States。They madeexperiments and theoretical analysis。The study on the prefabricated cagesystem is just beginning abroad，and there is no report about it in China。The ductility is focused on in this paper，and the experiment of concretecolumns reinforced with prefabricated cage system under axial compression isdone。The main research work and conclusion are as follows:（1）This experiment were carried out in five columns axial compressiontest, in which four concrete columns reinforced with prefabricated cagesystem and one concrete columns reinforced with rebar reinforced system。Inthis experiment spacing of transverse steel was controlled to study theprefabricated cage system。（2）Thought the experiment we can know：the failure process of concretecolumns reinforced with prefabricated cage system is very similar to withrebar reinforced system，but the cover concrete of the concrete columns reinforced with prefabricated cage system spall off quickly； the smallerspacing of transverse steel，the higher bearing capacity the column have；theductility of prefabricated cage system is better than rebar cage system；thecapacity of absorbing energy can be improved by73.5%using prefabricatedcage system than rebar cage system；the bond between the concrete andreinforcement in prefabricated cage system is not better than rebar cagesystem；the stress of longitudinal steel relates to the position。（3）The stress formula of confined concrete is derived in this paper，considering the effect of spacing and form of transverse steel。Then thecompressive strength formula of confined concrete is derived by linear Moorestandards and the stress formula。...