Structural Behavior And Design Method Of Concrete Horizontal-hole Hollow Block Masonry And Walls

There are many shortcomings exsit in the hollow block with vertical holes,for instance hollow ratio is too small,poor thermal insulation,seepage and crack,inconvenient to install horizontal pipeline and poor seismic resistances.These shortcomings seriously hindered the application of the block building.To solve these problems,an innovative masonry walls system has been developed using a new type concrete hollow blocks with horizontal holes.The new type block keeps the advantages of traditional block with vertical hole and improves the deficiency.Due to the great differences of structural style between the new type block and the traditional block,the computational theory and design method of the current standards at home and abroad relevant traditional block cannot be directly applied in the new type block.It become a key problem to apply the new type block in engineering practice,which were establishing the new calculation theory and design method.The key problem includes the research on the basic mechanics performance,wall structural behavior,seismic performance,thermal performance and construction technology.In this dissertation,the structural behavior and design method of new type block masonry and walls were researched from the domestic and international norms,experimental study,numerical analysis,and the main contents was divided into there sections elaborate as follows.The first part was to resolve the static calculation and design problem of the new type masonry.The basic mechanics behavior of the new type masonry were tested,the deformation characteristic,failure mechanism,cracking load and failure load of new type block masonry were obtained.The influences of the different block strength,mortar strength and block size on masonry compression behavior were observed.The stress-strain formula and elasticity modulus computational method for the new block masonry have been proposed by using a logarithmic function model.Based on the experimental results and referenced the current national standards a new compressive and shear strength formula were proposed.The second part,on the basis of the above study,the new design theory and structural measures of the walls were proposed through theoretical deduction and experimental research.According to the classical elastic thin plate theory,the elasticity analytic solution of the wall was obtained used the heavy trigonometric series method.According to American codes,the calculation method of out-of-plane earthquake loading force was obtained.On this basis,seismic design method of the out-of-plane walls was proposed.An experimental investigation was carried out and seven full scale sandwich walls specimens were tested under in-plane cyclic loading.The failure mechanism,deformation ability,carrying capacity,hysteresis behavior,ductility and rigidity degeneration of the sandwich walls were obtained.The experimental parameters include the number of different seismic structural measures,construction methods,and height/width ratio of a wall,with or without a window opening in the wall.The characteristics of the seismic behavior and the influence of the experimental parameters of these wall specimens were discussed in this paper.The test results indicated the sandwich walls work well assisting the concrete frame,inside and outside leaf wall body coordination performance is good,the sandwich walls have good bearing capacity,deformability and seismic behaviors.The last part,on the basis of research of the new type block force behavior and design method,the research of thermal performance and engineering application research were conducted.The thermal resistance calculation method used numerical simulation was proposed based on the two dimensional steady state,the thermal resistance of the new type block was calculated by matlab program.A comparative analysis was done between the test results,finite element analysis results and the numerical simulation results.On this basis,a thermal resistance calculation method was proposed.In the last,a research on the construction methods,construction of breastsummer were done.The new type block achieved good economic and social benefits when applied to engineering.