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This paper is concerned about the lateral load response and associated working mechanism of a precast reinforced concrete shear wall involving horizontal connections. An assembling method is proposed using dry connection through a horizontal steel connector (H-connector) and high strength bolts. To investigate the effectiveness of such an assembling method, two identical wall-connector assembly specimens have been constructed and tested under monotonic loading and cyclic loading, respectively, while subjected to a constant vertical compression. The test results showed that the performance of the shear wall assembly was generally satisfactory in terms of ensuring the full development of the shear wall strength and ductility. To assist in the interpretation of the experimental results and enable further study on the design approach, a detailed mechanism analysis has been subsequently conducted. The stress in H-connector flange and shear force transferred through each high strength bolt has been deduced on the basis of mechanism analysis. The further sliding analysis within the bolted connections agrees well with the experimental results and therefore confirms the derived formulae for H-connector and high strength bolt.high-strength bolt, horizontal steel connector, precast shear wall, relative sliding, working mechanism 1 | INTRODUCTION Precast reinforced concrete (RC) construction is common in many parts of the world. Typically, it involves the mass production of repetitive and often standardized units, namely columns, beams, floor, and roof elements, and wall panels. Advantages of precast construction include less labor cost and shorter construction time, as well as better quality control. Precast RC structures with special detailing and treatment at the connections are also popular in seismic regions, and lessons are continuously being learned. 1 However, comparing with other precast components, precast RC shear wall is relatively under-developed, and this has become a bottleneck problem in the precast construction of medium to high rise buildings in seismic regions.As it is well known, shear wall is an essential structural member to resist lateral seismic loading in high rise buildings. 2 Due to the need of maintaining high lateral stiffness and resistance, precast RC shear wall poses particular challenges to the assembling techniques. Although there has not been a well-established approach, researchers worldwide have carried out investigations on various kinds of prefabricated RC shear walls. In general, the assembling approaches adopted in these RC shear walls can be classified broadly into two main categories, namely "dry" and "wet" methods.A series of experimental and analytical studies were performed on the unbonded posttensioned (UPT) precast concrete wall system. 3-6 The UPT system is normally Discussion on this paper must be submitted within two months of the print publication. The discussion will then be published in print, along with the authors' closure, if any, approximately nine months after the pr...

This paper is concerned about precast reinforced concrete shear walls and the methods of assembling shear wall panels to form a reliable load transfer system. An assembling method is proposed using dry connection through a horizontal steel connector (H-connector) and high-strength bolts. To investigate the effectiveness and the design of such a connection method, three wall-connector assembly specimens with different connection details have been constructed and tested under monotonic loading while subjected to a constant vertical compression. The test results provided comprehensive data regarding the progressive transition of the load transfer mechanisms and showed that the performance of the shear wall assembly was generally satisfactory in terms of ensuring the full development of the shear wall strength and ductility. To assist in the interpretation of the experimental results and enable further parametric analysis, a detailed finite element model has been developed with incorporation of the main load transfer mechanisms, in addition to the description of the nonlinear behavior of the shear wall. The finite element model has been verified to represent well the actual behavior of the shear wall assembly, and it has provided further insight into the occurrence of slippage at the connection, the development of the bearing resistance of the bolts and the compression load transfer through contact in the later stage of the response.

This article is concerned about precast reinforced concrete shear walls and the methods of assembling shear wall panels to form a reliable load transfer system. An assembling method is proposed using dry connection through an H-shaped steel connector (H-connector) and high-strength bolts. A preliminary design, including the H-connector design and bolt design, has been carried out based on the force analysis on the vertical connection in the wall assembly. On the basis of the finite element analysis verified by an experimental study, the preliminary design has been confirmed and a monolithic coefficient ( ζ) has been used to evaluate the cooperative working performance of the two parallel shear walls. Then this article continues to carry out a finite element parametric study on the mechanical behaviour of the precast reinforced concrete shear walls with varying parameters, which includes the bolt specification, the frictional coefficient on the contact surface within the bolted connection and the thickness of the H-connector flange. The lateral load bearing capacity, lateral stiffness and cooperative working performance of the wall assemblies involving these varying parameters have been broadly analysed.

In order to verify the viability of the new-type vertical joints (composed of high-strength bolts, connecting steel frames, embedded limbic steel frames, and steel sleeves) in an innovative prefabricated structural wall (IPSW) system, low-cyclic reversed loading tests (pseudo-static tests) were performed on two H-shaped test specimens fabricating from precast web wall panel and precast flange wall panels joined together through the novel vertical joints. On the basis of the loading procedure and test data, the global behavior (including failure modes, lateral stiffness, ductility, and energy-dissipating capacity) and the local performance (including the stress distribution in the connecting steel frames and the relative slippages between the connection components) of the test specimens were detailedly discussed and presented. The research results demonstrated that the connectors were strong enough for maintaining the web wall panel and flange wall panels work together as an entirety to resist lateral seismic force, no slippages occurred on the contact interfaces between the connecting steel frame and embedded limbic steel frame throughout the loading procedure, and the vertical shear stress at the midpoint of the connecting steel frame (close to zero) was far smaller than that at its lower end (still much less than its yield strength). This experimental research confirms the viability and reliability of the new-type vertical joints, although the configurations of the precast wall panel as well as the vertical joints need indispensable improving to optimize the seismic performance of the entire test specimen.