Experimental study on internal relative humidity response mechanism of#br#
recycled concrete based on coarse aggregate porous interface
Liu Chao1Liu Huawei1Zhu Chao1Bai Guoliang1,2
1School of Civil Engineering, Xi’an University of Architecture & Technology, Xi’an 710055, China; 2Key Lab of Structural Engineering
and Earthquake Resistance of the Ministry of Education, Xi’an University of Architecture & Technology，Xi’an 710055, China
Abstract：The durability of the recycled concrete structure can be affected by of its interior humidity fieldIn this work, based on the porous characteristics of the recycled coarse aggregate interface, the response laws and response mechanisms of interior relative humidity of recycled concrete (with 100% replacement ratio) and ordinary concrete are compared under different temperatures, different depths and different loadsThe results show that the interior relative humidity response rate of recycled concrete is faster than that of ordinary concreteThe closer to the surface of recycled concrete it is, the faster the relative humidity response rate (which increases with the temperature) shall beBending load may accelerate the relative humidity response rates of both recycled and ordinary concretes, but its effect on recycled concrete appears to be more significantFor the delayed rise phenomenon of relative humidity in the recycled concrete interior, the “partitioninterface heat and moisture transfer model of recycled coarse aggregate” is proposed, and the delayed rise mechanism of relative humidity is analyzedThe calculation model for relative humidity response of inner and outer environments of recycled concrete is established by the method of multivariant nonlinear curve segmentation fitting
