Experimental Study On The Fundamental Mechanical Property Of Regenerated Thermal Insulation Concrete(RATIC)post Freeze-thaw Cycles

China’s demand for new and rapid urbanization,paired with guidelines on resource saving,environmental friendliness and sustainable development,fuel the development of regenerated thermal insulation concrete(RATIC).Thanks to regenerated aggregate and insulation aggregate,RATIC can help reuse resources and reduce construction waste;it is also lightweight,energy efficient,inorganic and fireproof,and has good insulation property.These unsolved questions provide valuable topics for further research.Building on previous research on glazed hollow beads insulation concrete,the study involves mixing different ratios of regenerated aggregate to make RATIC.It studies fundamental mechanical property of RATIC under room temperature and post freeze-thaw cycles.Through this process,the degenerative patterns of mechanical property of insulation concrete post freeze-thaw cycles will be examined.Regression analysis on the concrete’s post freeze-thaw cycle mechanical property calculation formula is also presented.The study provides theoretical evidence and reference for the practical application of insulation concrete in construction.Main focuses of the study and conclusion are as follows:Experimental study was done on the fundamental mechanical property of RATIC under room temperature without freeze-thaw.Specifically,the effects of various regenerated coarse aggregate replacement rates on fundamental mechanical properties were investigated,their corresponding failure morphology were stated,and failure mechanism was analyzed.Experiments were done on RATIC,with various amount of regenerated aggregate mixed in,under various numbers of freeze-thaw cycles.The concrete was also compared against insulation concrete that had not undergone freeze-thaw cycles.The cube specimen’s apparent morphology,relative dynamic modulus of elasticity,mass loss rate and strength loss rate were analyzed and studied.Using constant expression,formulas for calculating the compressive strength,tensile strength and bending strength of the regenerated concrete cubes and prisms in relation to the number of freeze-thaw cycles were established.From the experiments,it is concluded that as the number of freeze-thaw cycle increases,the surface of RATIC becomes rough and uneven.Its exterior tends to be loose and crumbling,with corners missing and both coarse and fine aggregate appearing.As the number of cracks grows,so does the width of the cracks.The cracks extends into the interior of cube specimen.Frost heaving effect results in the water inside the cube specimen being frozen,thus increasing its mass.Later,due to freeze-thaw cycle effect,the surface crumbles,hence reducing the mass.The more regenerated aggregate is mixed in,the greater the loss of mass as the number of freeze-thaw cycle increases.The strength of RATIC under various regenerated aggregate replacement rates presents a linear decreasing.As the number of freeze-thaw cycle increases,the RATIC’s degeneration rate of the compressive strength indicator first changed slowly,then more quickly,while the degeneration rate of splitting tensile strength had a steep drop(significantly decreased in the early stage,then decreased at an accelerating rate,and finally it decreased drastically).The static modulus of elasticity remained constant.