Masakazu Terai

Fracture Behavior and Mechanical Properties of Bamboo Fiber Reinforced Concrete

Fiber reinforced concrete is superior to plain concrete in toughness, which is the energy absorption at fracture. This study is intended to use fibers extracted from bamboo for tensile reinforcement of concrete. Some experiments were carried out to explore the possibility of bamboo fiber reinforced concrete. As a result, the compressive strength of concrete with 1-2% bamboo fiber is little different from the case without reinforcement. On the other, the splitting tensile and the flexural strength significantly increased with an increased volume fraction of fibers. The strength of bamboo fiber reinforced concrete increased with increasing fiber content as a result of fiber bridging.

Seismic Isolation of Base-Isolated Vending Machine With Air Dampers

By setting the isolation system between the foundation of the house and the foundation ground, it makes it possible to scale back the influence of the earthquake. A sliding isolator, which is compact and has high isolation characteristics, had been developed. This isolation system of the house have found effective and had high performance. This system was applied to the vending machine. Although the sliding isolator has been shown to be effective, it required the wide space around the vending machine. By using the base isolation combined with the air damper, it allowed to use in the narrow space area. It is useful when the vending machine is set in front of the wall. A sliding isolator combined with air damper has high isolation characteristics.Copyright

Consideration of Scale Effect in Concrete Members

This paper investigates the scale effect in concrete members subjected to shear loading. Some concrete structural type (RC and SRC) of different sized test specimens were prepared and tested. Moreover, a shear loading test on some geometrically similar specimens, having diameters from d=300 to 1100 mm, was conducted in the present study to investigate the scale effect in large-scaled concrete structural members. The results clearly indicate that the size effect for large scale members is clearly observed. The validity of the ku value in Hirosawa’s equation ,which is the most popular shear design equation in Japan, is verified through the comparison with the test results on 37 RC and SRC specimens failing in shear, 14 specimens were collected from this paper and 23 specimens from the works published recently. From the inverse analysis of ku, it is important of the review of ku for the seismic design of large scale structures.

Development of Base-Isolation House Using Sliding Device

By setting the isolation system between the foundation of the house and the foundation ground, it makes it possible to scale back the influence of the earthquake. A sliding isolator, which is compact and has stable isolation characteristics, had been developed. It was made of a plate with multi convex cell and a sliding plate. This system is a sliding isolator with multipoint contact. The static tests, the shaking table tests and analysis were conducted to confirm the damping capacity of the sliding device. In the element tests, the coefficient of static and dynamic friction and the change in the friction of the total system resulting from construction error were investigated. Movement of the base-isolated house and twisting of the base-isolated house with eccentric load under the actual earthquake loading were surveyed in the shaking table tests. As a result, it was effective and had a stable performance.Copyright

Development of Passive Controlled Structure Assembled With L-Type Diaphragm

Using the high-strength bolted connection, it is possible to control the quality of the joint and improve the construction of the structure. By setting the energy absorption mechanism on the structure and enhancing the damping effect, it makes it possible to scale back the influence of the earthquake. Based on the statement above, a new type of beam column joint (L-type Diaphragm) was developed and tests and analysis were conducted to validate the performance of this joint and the energy absorption characteristics at the end of the beam were surveyed. The stress transfer mechanism of the joint was investigated in the shaking table test of the actual size frame structure with this joint. As a result, it was found effective and a higher reliability.Copyright