This paper shows the quantitative verification of the stress transfer performance of CLT compression areas and shear joints through the studies of the static elastic-plastic analysis and experimental results, and the following results have been achieved. ・ By assuming a stress state model of a CLT panel, restrained at the top and bottom by rigid bodies, with a horizontal force applied, the theoretical calculation formulas for the compression area width and horizontal stiffness of CLT have been developed. (Equations No. 1 to No. 8) ・ The compression area width found from the distribution of the vertical deformations in the joint areas in the experimental results was 70% and 81% of the theoretical calculation results, respectively, in the elastic limit and ultimate states, and 24% and 28% for the CLT width. ・ Since the compression stiffness of the CLT compression area tends to be proportional to its compressive Young's modulus, the stiffness calculation formula is proposed, where the compression stiffness is generally 1/290 of the Young's modulus. (Equation No. 13) ・ The results of the static elastic-plastic analysis performed using the above compression stiffness calculation formula were in good agreement with the experimental results. ・ The further study on the deformation of the CLT compression springs of the analysis model revealed that a curvature occurred in the distribution of vertical deformations due to the curvature of the steel beam. Furthermore, it was found that the width of compression area was reduced to on average approximately 80%, compared with the assumed linear distribution. ・ The formulas to calculate the coefficient of reduction of the compression area width from the theoretical calculation values were derived from the parametric study using static elastic-plastic analysis on the relations between the ratio of the rotational stiffness of CLT to the curvature stiffness of steel beam and the width of compression area.(Equations No. 23 and No. 24) ・ On the basis of the above findings, we have developed the formulas for the compression bearing capacity of CLT in the elastic limit and ultimate states (Equations No. 25 to No. 33), and confirmed that the results calculated using the formulas were in good agreement with the experimental results.

We have developed the new hybrid structure of CLT infill and steel frame for middle-rise and high-rise buildings. This structural system can achieve the high structural potential of the CLT panel by holding around the CLT panel with steel frame. Steel frame can support sustained load of a high-rise building without CLT panels and can build long-span beams reasonably. Compression stress of CLT seismic panel can be transmitted to the upper and bottom steel beams through high strength mortal layer, and the steel beams can secure high shear strength as boundary beams. Shear of the CLT panel is transmitted by drift pined joints with insert-steel gusset plate. And tension stress balanced with compression stress of CLT is supported by steel tie bar. To clarify the performance of this structural system, we have conducted the structural experiment series with seven test frames in 1/2 scale. The result of the structural experiment series provided the following findings. Firstly, all of the CLT specimens reached compressive or shear failure, and performed to their full structural potential. Because of that, it has been found that it is possible to perform structural design that takes advantage of full CLT performance. The structural performance has increased up to max. 3.48 times for the horizontal stiffness and up to max. 2.67 times for the horizontal bearing capacity, by inserting CLT panels into the streel frames. All CLT panel showed slip type restoring force characteristic. In case of shear failure, the decreases in shear force were caused at story deformation angle greater than 1/71 radian. In case of compression failure, the decreases of shear force were gradual, and their deformation performances were excellent. It has been found by the experiment series that these failure modes of CLT depend on aspect ratio (H/L) of CLT, and in case of low H/L, shear failure tends to occur. The shear strength and elastic shear modulus of test frame CLTs in shear failure could be reduced to about 70% of the material shear test. When the story deformations of the CLTs are separated into the deformation components of shear deformation, slip displacement of the joints, and rotational deformation of the CLTs, the rotational deformations of the CLTs are the largest. And the rotational deformation ratio of story deformation tends to increase by H/L of CLT Based on the above findings, a subsequent paper will show the detail study on compressive stress transfer in the upper and bottom surfaces of CLT with analytical studies, and propose structural design and stress analysis method of the structural system.

The object of this paper is to make clear the shear transfer mechanism and the shear displacement behavior in the connection of Half Precast RC member. The experiment and the 2-D non-liner finite element analysis were performed on the RC beam with horizontal joint. The study for five specimens whose parameters were joint steel bars and concrete shear-key was carried out. The results are as followed. The influence of shear resistance elements was examined based on our several experimental studies. The shear transfer mechanism and the shear displacement behavior at the interface can be explained by the author's model of shearing force - shear displacement relationship in connection of precast concrete.

ポリエステル系樹脂およびセメント系固着剤を用いた接着系あと施工アンカーを,コンクリート圧縮強度が10～24N/mm2の低強度コンクリートに施工した場合の引き抜き力とせん断力に対する構造性能を把握するために実験を実施した。本実験で得られた実験結果,および,現状の接着系アンカーの設計式の基になっている実験データの耐力・変形性状を検討することにより,既往の設計式による耐力評価,および,引き抜き力とアンカー筋の抜け出し量との関係,せん断力とせん断ずれ量との関係を把握し,低強度コンクリートに対する適用性および接着系あと施工アンカーの構造特性に関する知見を得た。

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