Experimental And Theoretical Research On The Mechanics Behavior Of Autoclaverd Fly Ash Brick Masonry

Autoclaved fly ash brick has many advantages, for example, low carbon, energy-saving, recycling, etc. Due to backward production technology, the durability of brick is bad in the early days. So its use is limited. At present, through improving the pressure molding process, the strength and durability of bricks are improved. In order to properly apply the new autoclaved fly ash brick, and provide test and theoretical basis for compiling "Technical code for autoclaved fly ash brick buildings", the following jobs are done in this paper:The autoclaved fly ash brick masonry axial compressive performances are researched based on experiment. That the mortar strength influence on the compressive strength of masonry is considered. And the mechanical properties are compared with fired clay brick masonry. There are 45 masonry specimens in test. The working mechanism of compressive masonry are analyzed. Autoclaved fly ash brick bricks masonry compressive strength calculation formula are given according to statistics and elasticity theory. And design index of compressive calculation of autoclaved fly ash brick masonry are given.The shear performances of along the seam section are research. Normal mortar and special mortar of different strength grade are compared in test. There are 78 masonry specimens in test. And the shear properties are compared with fired clay brick masonry. Shear strength calculation formula of autoclaved fly ash bricks masonry are given. And the design index of shear calculation of autoclaved fly ash brick masonry are given.The constitutive relationship of autoclaved fly ash brick masonry is researched. According to measured stress-strain curve and compared with the domestic and foreign relevant research, constitutive relationship expression of autoclaved fly ash brick masonry is given with the logarithm function forms and polynomial form. Design index of elastic modulus and poisson's ratio of autoclaved fly ash solid and perforated bricks masonry are given by the mathematical statistical analysing of the test datas.The influence of eccentricity on compressive performances of autoclaved fly ash brick masonry is researched.52 masonry samples are tested. The stress and deformation performances, failure process and features are studied. And the mechanical properties are compared with fired clay brick masonry. ANSYS finite element analysis software is used for simulating masonry subjected to eccentric load. By theoretical and statistic analysing test and simulate datas, the formula of eccentric bearing capacity of autoclaved fly ash brick masonry is given, and the eccentricity limits is also given.The influence of ratio of height to sectional thickness on compressive performances of autoclaved fly ash brick masonry long columns are researched. Firstly, compression tests were conducted on 21 samples of masonry column with different ratio of height to sectional thickness. Failure process and variation rules are researched. The development regular of load-deflection curves, load-axial deformation curves and stress-strain relations are researched. Secondly, the mechanical properties are compared with fired clay brick masonry long columns. Again, ANSYS is used for simulating masonry long columns subjected to axial load. Finally, The formula of masonry long column axial compressive bearing capacity is given by comparing test and simulate datas to code formula calculation values, and the allowed ratio of height to sectional thickness of autoclaved fly ash brick masonry long column component is also given.