The Experimental Research On Fiber Reinforced Ceramsite Concrete About High Temperature Performance

Lightweight aggregate concrete with a bulk density of small,good thermal insulation properties and other characteristics.In addition to being widely used in industrial and civil construction of the wall and the load-bearing structures,it can also be used for bridges,poles,Chimneys,refractory lining of high-temperature furnace and other special structures.But it lack of the study of fire-resistant performance and post-disaster damage assessment and repair about lightweight aggregate concrete structure,and some only stay in a qualitative study,the research on domestic are at the initial stage,the depth and breadth of research are less than ordinary concrete,but also lack of appropriate fire-resistant design specifications and technical regulations.In view of this situation,this article discussed on mechanical properties and microstructure on lightweight aggregate concrete after high temperature.In this paper,Experimental study on high temperature performance for six different types of concrete,first of all,starting from the residual strength to analysis of the changes in laws and mechanism about concrete under high temperature performance,and given the proposed formula for calculating;Observation the concrete micro-structure after different temperatures of different types,different parts which use electron microscopy(SEM-EDAX)which have energy dispersive X-ray spectra instrument;and preliminary study carried out of the lightweight aggregate concrete in engineering applications.The results show that:(1) the lightweight aggregate concrete after high temperature residual strength curve formula which Statistics given are in good agreement with the experimental results.(2) The best high temperature of all-lightweight aggregate concrete,followed by sand lightweight aggregate concrete,the worst of ordinary aggregate concrete.(4) After high temperature the lightweight aggregate concrete have changed in color and lossed in quality.(5) The microstructure will produce a series of changes after heating,at different temperatures,the C-S-H gel,Ca(OH)₂ crystals and the interfacial transition zone between aggregate and colloidal and other microstructure have different characteristics,these features can be used to explain the main reasons for changes of the concrete performance indicators after the high temperature,to provide technical basis for the application of lightweight aggregate concrete in the high-temperature environment.