Differential settlement occurs frequently as typical seismic damage of building mainly caused by its foundation damage. In order to avoid this type of damage, it is important to do carefully construction work as well as to make aseismic design of foundation by grasping ground condition rightly. Problems on aseismic design of foundation are classified into several groups as follows: general problem, earthquake input problem, assumption of collapse form, structural plan of foundation, evaluation method of soil condition, design calculation, structural properties of pile and boundary condition of pile head. It is necessary to solve these problems one by one, to systematize aseismic design of building foundation.

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Various test methods and estimation means on alkali reactive aggregate based on the results of specified test were reviewed in order to exclude the mixing of alkali reactive aggregate with concrete and to avoid the deterioration of concrete by alkali aggregate reaction. The present test method does not work well in individual and there is necessity to combine several test methods to obtain more certain and convincing conclusion. It was also pointed out that refined analysis of reaction and expansion mechanism in alkali aggregate reaction, identification of alkali reactive aggregates and determination of their allowable limit of content, elimination of expansion of aggregate caused by the reaction other than alkali aggregate reaction, verification and theoretical clarification of pessimum condition, selection of scale factor and testing condition to improve the correspondence to the concrete deterioration in actual environmental conditions were indispensable factors to be solved to establish more reliable rapid test method for minimizing alkali aggregate reaction.

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The covered coal storage yard for unit No.3 of Takehara thermal power plant of Electric Power Development Co., Ltd. is an enormous structure, for storage of total weight of 150000 tons of coal, composed of cylindrical reinforced concrete and dome-type steel roof. As the loading conditions of massive coal and structural features are unprecedented, measurement for stress estimation at each portion has been conducted shortly after the start of acceptance of the coal, by using strain gages, load cells, pressure meters and thermometers which had been embedded in the structural members. Using the measured strains of reinforcing bars, the section forces of each structural members are estimated, while overall loadings of the structure are formulated by referring to the measured values by pressure meters and thermometers. Stress analysis by Finite Element Method of which model is the same as that used in design stage is then conducted to make comparison between the analyzed section forces and the estimated ones. It is concludingly found that the analysis results are almost identical to the measured ones, which, in turn, proves that several assumptions and methodologies taken in the design stage are verified as well as confirmation for the structural safety.

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