The Residual Performance And Safety Assessment Of Recycled Aggregate Concrete Column After Fire Sprinkler

Reinforced concrete structure is the most widely used in the current building structure.While the reinforced recycled concrete structure,possessing the excellent performance of reinforced concrete structure as well as solving the problems of disposal construction waste and serious damage to environmental resources,which enables construction resources to be recycled,has a board application prospect.Building fire is a thorny problem that all buildings must face,and water cooling is most common used to cool buildings in fire.However,the research on the performance of reinforced concrete after high temperature water cooling are rare,so it is necessary to study about this.To study the residual properties of reinforced recycled concrete specimenunder the axial compression after high temperature water cooling,26 Spiral stirrup recycled concrete specimens weie designed and manufactured,which the recycled coarse aggregate replacement percentage,maximum temperature,stirrup spacing and cooling methods were considered to be the varying parameters,and axial compression tests were carried out on specimens after high temperature water cooling.The test observed the characteristic of specimens before and after high temperature water cooling as well as specimens failure process and final forms.meanwhile the acquired load-displacement curve of specimens,and the influence of various parameters on the bearing capacity,initial stiffness and ductility etc is analyzed.The results of study showed that the spiral stirrup columns have good fire resistance,and the bearing capacity of spiral stirrup columns decreases only about 10%after high temperature water cooling at 800 °C.It also suggests that the replacement ratio have little effect on the mechanical performance after high temperature water cooling while the influence of maximum temperature and cooling methods on the mechanical performance of specimens in different temperature ranges also varies.But the spacing of spiral stirrups will have a significant effect to the mechanical performance of specimens.Finally,according to the apparent changes of the test specimens,loss of ignition rate,rebound strength,the evaluation method of residual performance of reinforced concrete specimens after high temperature water cooling is proposed.