| Multi-ribbed slab structure (MRSS) is a new structural system, characterized by low weight, high strength, saving energy and good aseismic performance. Though much progress has been achieved in previous study, there still remains a lot to be studied and perfected. The thesis is devoted to study on the multi-ribbed slab wall, the main bearing member in MRSS, including its mechanism, failure mode, aseismic capability, mechanical models, ultimate bearing capacity and aseismic design based on control. The paper mainly accomplished such work as follows:1) Based on test research on multi-ribbed slab wall, the paper proposed the member's failure modes under horizontal loads, analyzed the co-performance between the inner frame and the infilled silica bricks and that between the slab and the outer frame, discussed the wall's bearing capacity, rigidity, deformation, ductility and energy dissipation ability in different modes, and put forward a simplified mechanical model of the slab wall under vertical loads.2) Nonlinear FEM was employed to simulate the whole process of changing internal force and deformation, the appearance and development of cracks, and to describe the failure mode and the ultimate strength capacity level. In addition, proven analysis model can provide more information so as to break the limits of test study.3) According to test study and theoretical analysis, the paper suggested different mechanical models for different stages. (1) Elastic stage. The wall was equaled to an elastic composite slab with silica bricks as main body and concrete rib beams, columns and outer frame as reinforcing fiber. (2) Elastic-plastic stage. The wall was equaled to a rigid frame-oblique compression bar model in which concrete frame was equivalent to a rigid frame while silica brick was equivalent to a oblique compression bar. (3) Failure stage. The wall was equaled to a beam-hinged frame. Furthermore, the paper proposed a rigidity formula of continuous function based on damage theory.4) On the basis of previous study on elastic stage, the paper put forward two orthotropic composite material models, twice reinforced model and bi-reinforced model, and also a simplified isotropic material model for engineering.5) Based on test results and going by ultimate balance theory, the paper drew anti-shear formula of the wall under eccentric loads, and discussed the main factors which influenced its anti-shear bearing capacity.6) Based on plain section assumption, the paper studied the normal section bearing capacity of the wall. Stress, strain and deformation computation was combined to establish bearing capacity formulasfor the normal section under moment, unaxial loads and axial loads respectively.7) Based on the formulas of oblique section bearing capacity and normal section bearing capacity, the paper set rules to determine the failure mode of the wall and gave several main factors.8) The paper, according to test simulation and theoretical computation, suggested a retrogressive qua-linear restoring force model, proposed possible failure modes under earthquakes and the reasonable failure mode, probed aseismic design method, and advised detail requirements.The originality of the thesis lies in:1) To establish different mechanical models for different stages. During elastic stage, the wall was equaled to an elastic composite slab. During elastic-plastic stage, the wall was equaled to a rigid frame-oblique compression bar model. During failure stage, the wall was equaled to a beam-hinged frame. Furthermore, the paper proposed a rigidity formula of continuous function based on damage theory.2) To improve the elastic caculation model of composite material. Based on previous study, the paper put forward two orthotropic composite material models, twice reinforced model and bi-reinforced model, and also a simplified isotropic material model for engineering.3) To put forward simplified models. By means of nonlinear FEM, the whole process of changing internal force, the de...
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