Volume Change Load And Stress Analysis Of Wall

Masonry wall using the new non-sintered material, increasing the wall drying shrinkage, especially the insulation wall change the temperature field, the wall volume change increased rapidly.Volume change caused wall stess, when the stress exceeds the failure strength of the wall, the wall cracking and effect the normal use of the structure,So crack has been a pivotal problem t0 be solved urgently.The influencing factors mainly include material drying shrinkage,different area, different toward, different color,different forms of insulation, different insulation materials and so on.Based on the existing wall temperature load ,the further analysis the volume change load and stress of the wall.For single-layer walls under periodic harmonic heat, the heat transfer differential equation in first boundary condition was solved by variable separation, and the analytical solution for quasi-steady temperature field of single-layer wall was reached. This solution was applied to multilayer energy-saving wall and roofing by the superposition method, and provided a basis for thermal stress analysis. Inner and outer surfaces air of wall was respectively as a layer with thermal resistance and without heat capacity, and the analytical solution of temperature field of multilayer wall was obtained while considering heat exchanger between the wall and the air.Based on series of fulvic, the indoor and outdoor air synthetic temperature simplified steady temperature field (annual temperature difference) and the effect of non-steadyharmonic heat temperature field (daily range of ground temperature). To Harbin, Beijing, Changsha, Guangzhou, four representative areas in three different forms of insulation, three different conditions were analyzed by volume deformation load, The results show that outer thermal insulation can be an effective thermal barrier on the outside harmonic heat.Finally, According to the foundation constraint the masonry wall bound volume change produced vertical cracks at the bottom, this paper take bottom constraint long-wall approximate analysis to analyze the stress of concrete masonry wall. The results show that cracks in concrete masonry walls mainly caused by the maximum horizontal tensile stress; horizontal resistance coefficient of foundation, wall length, wall height length ratio (wall high) have a greater impact in the maximum horizontal tensile stress of wall bottom and the minimum crack spacing of the wall .The article proposes the minimum crack spacing formula of masonry walls and crack control measures of wall.