Study On Mechanical Properties Of Autoclaved Fly-Ash Aerated Concrete Composite Block And Seismic Performance Of Frame Structure Covered With In-filled Wall

Nowadays,The world is facing the extreme problem of glabal resources shortage.Especially,the energy consumed in building has soared up,accounting for a tremendous amount of the social resources consumption.Therefore, it is becoming a concentrate area for experts and scholars to examine how to decrease the energy consumption of buildings.Around the developed country,organic building,sustainable building,zero energy consuming building,etc are the cutting-edge new ideas.China has already carried out building energy-saving,targeting65%.With the implementation of65%building energy-saving targets, a single block of material is difficult to meet the demands of filling wall construction insulation energy-saving targets,development and application of new type thermal insulation block is imminent.Through the mixed use of different types of materials,it is able to combine the benefits of them. And this has become the new idea to the creation of the new wall insulation block. As the province of coal production and consumption,Shanxi has a large mount of fly ash due to the thermal power.These fly ash has a large accumulation.However, only a small amount being used at present.This thesis has been studied on basic mechanical properties of autoclaved fly-ash aerated concrete composite block and seismic performance of frame structure covered with in-filled wall.It provides theoretical basis for the use of frame structure covered with in-filled wall being made up of autoclaved fly-ash aerated concrete composite block.It also solves the critical technical issues for the preparation of shanxi project construction standard "Specification For Wall Self-insulation of Autoclaved Fly-Ash Aerated Concrete ".At the same tim,It also solves the problems of fly ash comprehensive utilization and environmental pollution caused by accumulation of fly ash.In this thesis,Autoclaved Fly-ash Aerated Concrete Composite Block is made of autoclaved fly-ash aerated concrete block and polystyrene board via composite polymer adhesive mortar into a new kind of sandwich composite insulation block.Among them, the outer leaves block is B07grade autoclaved coal ash aerated concrete block,the inner leaf block is B06levels autoclaved coal ash aerated concrete block.Through theoretical calculations,the composite block along the wall thickness direction250mm (outer leaves block50mm, polystyrene board50mm, inner leaf blocks150mm) can meet energy efficiency standards65percent in the cold district.In this thesis,We take the250mm thick Autoclaved Fly-ash Aerated Concrete Composite Block for study, expand the following work:(1)Compressive strength test of the inner leaf block, compression test of polystyrene board and connection strength and compressive strength along the thickness of composite block test have all been carried out.The test result indicate that the compressive strength of the inner leaf block and polystyrene board,the connection strength along the direction of the thickness of composite block and the compressive strength of composite block have all reached the standard of "composite thermal insulation brick and composite insulation blocks"(GB/T29060-2012). The compressive strength of the polystyrene board also meet the standard of "adiabatic molded polystyrene foam"(GB/T10801.2-2002) in the test.(2)Nonlinear analysis of the autoclaved fly ash aerated concrete block wall filled composite single monolayer cross-frame structure and an empty frame with various construction method (set structural columns, horizontal tie beam, structural columns and horizontal tie beams)under horizontal load has been done with the powerful generally used ANSYS software.By comparing of load-displacement curve and stress nephogram, it is found that the lateral stiffness and the horizontal bearing capacity of frame structure covered with in-filled wall being made up of autoclaved fly-ash aerated concrete composite block adopted the different seismic structural measures have all been improved in different degrees.It is also found that the stress distribution of fly ash autoclaved aerated concrete composite block walls filled with structural measures tend to be conformed with and the stress of the column joints of the wall and the area along the diagonal of the wall is relatively large. So,we suggest that the connection method between wall column could adopt release method and prevent cracking of the composite block filler wall along the diagonal direction of the wall and wall column direction by double seam along both sides of the wall of each through a long set with steel mesh width consistent at the interface between wall column.(3)In order to investigate the fluence on anti-seismic performance of reinforced concrete frame structure by the lateral stiffness of frame structure covered with in-filled wall being made up of autoclaved fly-ash aerated concrete composite block and take the optimization of the effect of heat preservation and energy saving into consideration at the same time, build the autoclaved fly-ash aerated concrete composite block as glass beads bearing concrete frame structures covered with in-filled wall being made up of autoclaved fly-ash aerated concrete composite block and establish a six floor C35level insulation glass beads bearing concrete frame structures covered with in-filled wall being made up of autoclaved fly-ash aerated concrete composite block with three kind of models which are reinforced frame without in-filled wall; reinforced frame covered with in-filled wall; the frame structures with weakness story at bottom respectively. Modal analysis, response spectrum analysis and Nonlinear dynamic time history analysis under the frequently occurred earthquake of these three models have all been done with SAP2000software. The analysis result indicated that the decrement factor of cycle of C35level insulation glass beads bearing concrete frame structures with and without infilled wall are0.71and0.75respectively, larger than the recommended value which is0.6-0.7. So we suggest take the the decrement factor of cycle of the C35level insulation glass beads bearing concrete frame structures covered with in-filled wall being made up of autoclaved fly-ash aerated concrete composite block as0.7-0.8.Without infilled wall on the bottom, the structure’s vertical stiffness will tend to be not even, so as to form a thin layer on the bottom and cause sudden change of maximum displacements maximum drift, drift angle between layers, shear layers are formed mutation at bottom of the bottom.In the layout of in-filled wall being made up of autoclaved fly-ash aerated concrete composite block, we should follow the structure requirements of the specification and the arrangements of in-filled wall should be even. If is unavoidable, then ws should take reinforcement measures such as increasing the bottom reinforcement beams and columns; At the same time, we suggest to further improve the specification, considering the contribution of in-filled wall to the structure stiffness in the early stage.