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Autoclaved fly ash brick uses fly ash and lime as the main raw material, adding an appropriate amount of gypsum and aggregates, then water and mixture them, make them into billet by hydraulic mechanism, then they are autoclaved into solid brick or cell brick which is a new kind of wall materials. the use and generalization in construction are beneficial to saving land, saving energy, comprehensive utilization of waste and environmental protection. therefore, State decides to establish a unified national specification:“autoclaved fly ash brick structure technical specifications”, then promote its use. the tensile and shear strength of masonry are so low that its seismic performance is poorer, so the investigation to seismic performance is very important in the specification which will be establish. it has a direct impact to the use and generalization of this materials in the seismic areal. This paper does some preliminary studys on seismic performance, shear strength and failure mode of autoclaved fly ash solid brick walls, through the low-cycle loading test to five pieces of fly ash solid brick walls whose mortar strength are all M5. the study lays a solid foundation for the furture correlation study.The paper is broadly divided into the following four sections :①Introduction. the survey of masonry, the current situation of seismic on the fly ash brick walls and the source of topic.②Test survey . the choice and mechanical properties of test materials, the loading device, loading system,the test content and the description to test phenomena, failure mode of component and some related situations.③Analysis of test results. we analyze synthetically the various performance of the walls during horizontal earthquake through the failure mode of walls, the strain gauges, dial indicators, displacement meter of walls and the load-displacement hysteretic curve of the top of walls. Test shows: autoclaved fly ash brick walls have higher shear strength, better ductility and energy dissipation capacity , it is suitable for the use in low-intensity earthquake zone.④The seismic shear strength calculation of walls. we analyze the influencing factors on seismic shear strength of walls, and analyze emphatically the influence of constructional column to seismic behavior; introduct the existing calculation theory and formulas of masonry shear strength, and compaire two calculation formulars with test results.
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