Study On Self-stress And Bending Behavior Of Steel Bar In Autoclaved Aerated Concrete Slab

Due to the large construction area of many houses in China,the resources used and consumed by the construction industry account for a large proportion of life,so promoting energy conservation and environmental protection in the construction industry is of great significance for the protection of China’s environment and resources.At present,it is appropriate to select new energy-saving materials,and to create and improve existing building materials are the two most common ways of building energy conservation.Autoclaved aerated concrete has various advantages such as light weight,small thermal conductivity,convenient production,and high construction efficiency.In view of this,this paper proposes to replace the traditional concrete floor slabs with autoclaved aerated concrete slabs,and conducts research and analysis on the flexural properties of autoclaved aerated concrete slabs and the self-stress of the steel bars in the slabs.The test results were verified.The main contents of this paper are as follows:(1)The flexural test of two autoclaved aerated concrete slabs with different reinforcements was carried out through experiments.In the test,the development of cracks during loading of autoclaved aerated concrete slabs equipped with CRB600 H cold-rolled ribbed steel bars and HPB300 steel bars and the changes in mid-span deflection with load were compared and analyzed.The test results show that the cracks of autoclaved aerated concrete slabs equipped with CRB600 H steel bars develop slowly,and the spacing of the cracks is evenly distributed.At the same time,the deflection of the mid-span deflection increases gradually with the load after cracking.(2)Using the release method to measure the self-stress of the steel bars in the autoclaved aerated concrete slab,it can be concluded that after considering the self-stress,the cracking moment of the autoclaved aerated concrete slab is about 88.9% of the test value,which meets the expected design requirements.Moreover,the test proves that the self-stress of the steel bars in the autoclaved aerated concrete slab has a good effect on improving the crack resistance of the slab.(3)In this paper,ABAQUS finite element simulation software is used to test the flexural performance of autoclaved aerated concrete slabs with different types of steel bars.The finite element analysis results are in good agreement with the experimental results,and the simulation results also verify that the self-stress of the steel bars in the plate has a certain effect on the cracking moment and deflection value of the autoclaved aerated concrete plate.In addition,the finite element numerical simulation test compares the finite element numerical simulation results of three groups of differently reinforced plates.Under the premise of achieving the same bearing capacity,the reinforcement ratio of autoclaved aerated concrete plates equipped with CRB600 H steel bars can Relatively low,and the effective use of high ductility cold-rolled ribbed steel bars can not only meet the requirements of building capacity,but also save steel.