STRUCTURAL PERFORMANCE OF COMPOSITE STRUCTURE WITH CLT WALL INFILLED IN STEEL FRAMES USING DRIFT-PIN WITH STEEL PLATE

<p>　In Japan, Cross Laminated Timber (CLT) is attracting attention as the way of using forest resources that have reached cutting time. CLT is expected to be used for middle-to-high-rise building with making use of stable in-plane shear performance. In particular, composite structure with steel frame structure or reinforced concrete structure can take adventage of respective material properties, and more and more this kind of researches are reported in recent years. A previous research shows the estimation of drift-pin joint with steel plate for fastening CLT and steel frame. This research aims to confirm the structural performance of steel frame with CLT shear wall using drift-pin joint by conducting the design for this specification, pre-analysis for experiment, 1/2 scale experiment, joint test and material test, and to make analysis model which follows the experimental result. </p><p>　Firstly, one specification of the joint is defined based on the research of Ministry of Agriculture, Forestry and Fisheries conducted in 2016. It was assumed to insert CLT into a standard span steel frame at the design stage. The design stage takes following steps. 1) Determination of cross section of steel frame and module 2) Determination of CLT type 3) Design of joint 4) Grasp the properties of drift-pin joint 5) application to experimental scale. We use finite element analysis software (SNAP) at 3&5 step to model a drift-pin joint based on beam theory on the elastic foundation and get load-displacement relationship of unit drift-pin joint. SNAP was also used to analyze the 1/2 scaled experiment to model a steel frame, CLT panel, spring of drift-pin joint, and CLT compression spring, and incremental analysis. </p><p>　In 1/2 scale experiment, in total of four specimen in different strength grade of CLT or insertion position as parameters are tested. Fig.9 shows the results of the experiment. None of the specimens significantly reduced the load before reputation of controlled deformation angle of 1/30 rad. By inserting a CLT panel, the maximum load increased 1.2 to 1.4 times and the initial stiffness increased 1.5 to 2.3 times, confirming that inserted CLT panel performed as a seismic wall sufficiently. The stiffness of the average shear stress of the CLT almost matched with the shear modulus of the CLT in the material experiment (Fig.11) </p><p>　Fig.15 shows the analysis model after the experiment using the material properties which is obtained from material tests. Fig.18 shows the Comparison of the experiment to analysis results. The experimental results and the analytical results were in good agreement, and the behavior was able to be reproduced by the analytical model, comparing the timing of yielding of the members and the stress state at the specific deformation angle. </p>