The moisture content of concrete affects the ultrasonic pulse velocity and compressive strength. This effect adversely affects the estimation of the concrete compressive strength by ultrasonic testing. Therefore, this study conducted ultrasonic and compressive tests on dry concrete specimens. By applying the measured experimental results, this study proposed an estimation equation for concrete compressive strength that considers the effect of the moisture content. The proposed equation can estimate the compressive strength of dried concrete, concrete that has been dried and underwater curing again, and concrete that ha s been cured under standard curing conditions with an accuracy of about ±20%.

We focused on the regionality of crustal thickness and examined the differences in the scaling relationship between the seismic moment and rupture area for crustal earthquakes. We found good agreement between the scaling relationships and earthquake data when the saturated rupture width and stress drop was set to 16 km and 3.1 MPa, respectively, in regions with a relatively thin crust, including Japan, and set to 28 km and 2.0 MPa, respectively, in regions with a relatively thick crust. For crustal earthquakes, the accuracy of the scaling relationship is improved by considering the crustal thickness.

This paper proposes a design method for M-CK type tuned dynamic mass system considering viscous damping or hysteretic damping of base isolation structure. First, based on the fixed-point theory, the optimal design equation for an M-CK-type tuning system is presented, considering of the viscous damping of the structure. Next, we validate the proposed design method through simulation analysis. Finally, the proposed design method is proved by vibration experiments.

In general, long-term creep deformation and other factors affect the structural properties of arches and shells with large spans and low rises, but there is little information available. Existing structural design guides make assumptions based on limited information. In this study, we tracked the deformation of the large shell of the actual machine for 10 years from the time of construction, and identified the expansion, contraction, long-term creep, temperature deformation, and vibration characteristics immediately after placing concrete by measurement and numerical analysis. We will report on a case where we tried to comprehensively analyze the effects on the structural characteristics.

This study summarizes the results of horizontal two-dimensional and horizontal one-dimensional loading experiments using Dougou of Demitsudo-gumi and Hiramitsudo-gumi while applying a vertical load of 20kN to Dougou. The findings obtained are as follows.

1. It was confirmed that the effects of the two-dimensional force on the hysteresis curve are different between the Demitsudo-gumi and Hiramitsudo-gumi.

2. In both cases, no failure or load reduction was observed up to 1/10 rad under one-dimensional loading. It is inferred that during the two-dimensional loading of Dougong, tension occurred in the gap of Tojiri, and early shear failure occurred.

Concrete short-span beams might suffer bond splitting failure during a large earthquake due to their short development length. Steel Fiber-Reinforced Concrete is known to be effective in enhancing the performance of concrete members. However, there are not many studies on bond splitting failure of Steel Fiber-Reinforced Concrete members. Therefore, we carried out bond splitting tests of Steel Fiber-Reinforced Concrete assuming corner and side split type failures. We proposed an evaluation method for bond splitting strength considering their material properties. In addition, the evaluation method was verified using the results of tests of short-span Steel Fiber-Reinforced Concrete beams.

This paper presents prediction methods of moment-rotation relationships around strong axis of buckling H-Shaped beams subjected to a moment at one end. This paper studies the behaviors of the beams in two cases of boundary condition. In the one case, both ends are not restraint to rotate laterally and to warp. In the other case, the only loading end is restraint to rotate laterally and to warp. In order to improve the accuracy of the methods over various cross sections and spans, this paper checks that the lateral deformation and twist angle can be predicted accurately.

The effects of cyclic loading protocols on the structural performance of rectangular hollow-section members, such as the ultimate resistance determined by local buckling and the degradation behavior, are clarified through structural tests and elasto-plastic numerical analyses based on the finite element method. The material constants of the Chaboche model and the subloading surface model were identified using cyclic coupon tests to simulate the structural tests by the finite element method, and the analysis of rectangular hollow-section members subjected to bending shear was performed. Finally, evaluation formulae for the structural performance are proposed based on parametric numerical analyses.

For steel framed buildings with an eave height of 9m or less and beam span of 13m or less, bolt joints are permitted to connect the main structural members. This paper describes the effect of slip in bolt joint on the story drift angle of the frame, based on static loading tests and seismic response analysis of full-scale braced frames. Experimental results confirmed that the amount of increase in story drift angle can be evaluated according to the clearance of the bolt hole.

The objective of this study is to propose the new design formula for ultimate strength and allowable strength of slender concrete filled square steel tubular columns subjected to axial force and bending moment. This new formula is based on the full plastic strength, and has no slenderness classification between short, medium, and slender columns which is used in the current CFT recommendations. The proposed ultimate strength agreed very well to the analytical results whose parameters are material strengths, moment gradient ratio, column length - depth ratio and corresponded to the previous experimental results.