Experimental Study On Seismic Behaviour Of Low-rise Reinforced Concrete Shear Walls

RC shear wall is widely used in practical building for its larger carrying capacity,larger stiffness and better seismic performace.The shear wall used in the builing of with large space in ground floor and the bottom frame-the upper part of brick structure is generally the RC low-rise wall.The RC low-rise wall is also used in some special structure such as nuclear power plant structure.At present,the research on the low-rise wall focus on the shear span ratio between 1.0 and 1.5.It is not enough to study the seismic performance of shear walls with a shear span of less than 1.0 or even 0.5.At the same time,the existing researches mainly focus on the seismic performance of the shear wall under axial compression,and the research on the seismic performance of the shear wall under axial tension is not enough.In this paper,low cycle reciprocating test of 16 pieces of shear wall specimens with a ratio of less than(equal to)1.0 was completed.The main research wok and conclusions are as follows:(1)The seismic performance of the shear wall with low shear span was studied through low cycle reciprocating test of 16 pieces of RC shear wall.The influence of the shear span ratio,the axial load ratio and the horizontal reinforcement on the seismic performance has been explored deeply.The results of the experiment show that: with the increase of shear span ratio,failure modes of the specimens are changed from shear compression failure to flexural shear failure,and the carring capacity decreases significantly,but the ductility is greatly improved;Carring capacity of shear wall specimens increases with the increase of axial compression ratio;Tension greatly reduces the carrying capacity and the energy dissipation capacity;When specimens from compression to tension,the failure mode is changed form shear compression failure to shear tension failure.In the formula for shear capacity of shear wall in some countries,the test value is larger than the calculated value for shear compression failure specimens,the calculation values of European are larger than the test value for flexural shear failure specimens,all of the calculation values are not conservative for shear tension failure specimens.(2)Reinforced concrete shear wall low cycle reciprocating test was simulated by the nonlinear software Open SEES,and the numerical simulation results were compared with the experimental results.The results showed that the simulation of hysteresis curve obtained by simulation is consistent with the test results in loading path and unloading path for the shear wall with a shear span radio 0.75 and 1.0,and the corresponding displacement of peak load is relatively close,and it can also better reflect the squeezing effect of the reverse reloading of low shear span ratio shear wall.