| In this paper, a new ductile RC coupled shear wall, namely RC coupled shear wall with concealed bracings, was put forward based on the study of shear wall with concealed bracings and inclined across steel bars in lintel beam. Then the seismic design methods on shear wall with concealed bracings was given through the experimental study and theoretical analysis on seismic behavior and corresponding finite element analysis on elastic-plastic. The main contents are as follows:1. The influences of the reinforcement proportion of distributing bars to concealed bracings on bearing capacity, stiffness, deterioration process of stiffness, ductility, hysteresity capacity, energy dissipation and failure features of low-rise shear wall were studied through experiment analysis on 6 models of low-rise shear wall with concealed bracings under cyclic loading. And it showed that higher the reinforcement proportion of the concealed bracings, higher the bearing capacity of the specimens, but the proportion of the higher of the bearing capacity changed slowly gradually. In addition, the energy dissipation increased notably and almost linearly with the increasing of the reinforcement proportion of the concealed bracings. And the utmost elastic-plastic displacement and ductility coefficient of the RC shear wall with concealed bracings increased notably when the capacity didn't drop notably. And higher the reinforcement proportions of the concealed bracings, higher the elastic-plastic displacement and ductility coefficient. In a word, as the first line of defence, the concealed bracings have important effects in the aspects of confining the developing of cracks and increasing integrative seismic capacity.2. A new ductile RC coupled shear wall, named RC coupled shear wall with concealed bracings, was put forward. The influences of different reinforcement style of the concealed bracings and different span-height ratio of lintel beams on bearing capacity, stiffness and deterioration process, ductility, hysteresity capacity, energy dissipation and failure features of coupled shear wall were studied through experiment of 7 specimens under low cyclic loading. It illustrates that the new style shear wall has better ductility, energy dissipation and bearing capacity, especially the bearing capacity dropped indistinctively at anaphase of the deformation, the structure performance is stabilized relatively and can stay the appearance of the cracks.3. Through experimental and theoretic analysis it proved that it has more prominent effects in improving bearing capacity, the structure integer deformation and energy dissipating with concealed bracings in the two wall slabs than only with across inclined reinforcements in the lintel beams. And the key point of the RC coupled shear wall with concealed bracings is that concealed bracings can control the failure mechanism of the shear wall rationally. In particular,the concealed bracings have more evident effects in improving bearing and energy-dissipation capacity of the wall slabs in coupled shear walls with lintel beams of relative smaller span-height-ratio.4. The model of restoring force for RC shear wall with concealed bracings is established. And the mechanics model and the calculative formulas of the bearing capacity are presented also. The calculating results on bearing capacity and stiffness of the specimens were found to agree well with the actual measured ones.5. The finite element analysis model for elastic-plastic on RC low-rise shear wall and RC coupled shear wall with concealed bracings is set up with ANSYS finite element analysis program. In particular, different inclined angles and the bind core effect of concealed bracings are considered in the analysis. And the concept of concrete confined is introduced in the concrete of the rims, concealed columns and concealed bracings. With the modeling method in this paper, it is showed that numerical load-displacement curves agree well with the experimental skeleton curves, and that the errors of crack load are bigger, b...
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