The state of the art of structural design techniques and research work on reinforced concrete beams with openings is discussed. The openings pierced in web of reinforced concrete beams for piping, wiring, or ventilation have got common in the building structures in Japan. A lot of experimental research work have been carried out to obtain the data of the ultimate shear strength of beams with openings, and some equations to predict the shear capacity have been developed as well. A newly developed seismic design guidelines recommends the shear capacity equation based on a plastic theory. It is a big problem that there is quite a few cases when openings are pierced on a beam web while the structural designer knows nothing.

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Of the materials for concrete, those that are used in the largest quantity are, of course, aggregates, which make up around 70 % of concrete by volume. In Japan the demand for concrete aggregates is said to be 575 million tons or so in 1992. This paper first comments on change in use of concrete aggregates up to the present time, and subsequently reviews the recent trend of supply and demand of different types of aggregates as well as quality, precautions for use of aggregates, such as high-strength and high-durable concrete aggregates, artificial lightweight aggregates, iron-blast-furnace slag aggregates, ferronickel slag aggregates and recycled concrete aggregates.

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In recent years, many approaches toward harmonizing concrete construction with surrounding landscape are under investigation. Concrete always gives an impression of artificial objective because it has colorless and monotony. In order to make a favorable impression, the concept of landscape design that enables the concrete to make up as a new product is spreading over the field. This paper deals with the states and problems of pigmented concrete on coloring process and related matters from the viewpoint of color, which is one of important factors in landscape design.

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The Mitama-do is an ossuary, built at the Tokyo Tama Cemetery. The Reido, the main part of the buildings, has a shell structure in the form of an inverted cone with a maximum diameter of about 60 meters at the top and the thickness of 50 cm. The shell consists of narrow precast-prestressed concrete components (148 pieces in total and 20 meters in length) equally dividing the circumference into 144 sections. The components are factory-made and jointed by binding post-tensioning force at the construction site. This paper aims to report the outline of the building and the design and construction of the Reido's shell structure.

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A Man-made Island is being constructed in Hachinohe Port. As a means of connecting this island to the shore, construction of two bridges was planned. The main bridge is a two-span continuous, cable-stayed, prestressed concrete bridge, which has a length of 165.5 m and Japan's first independent single slanted (15 degree) tower. This bridge is located in a marine environment in a cold region ; therefore, it is necessary to consider many measures to insure the design and construction is highly durable.

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