If the forms, which are made of precast prestressed concrete and will not be removed later, have enough strength to support the weight of concrete placed on them, staging or intermediate supports can be neglected. Moreover, when the cast-in-place concrete combines well with the precast form panels to form a composite slab, it resists load effectively. This method is commonly called PCC SLAB Method and the characteristics of the slab with less crackings and small deflection for short and long terms loading is noteworthy. The problems regarding its applications have been clarified through various experiments carried by the author and others. He strongly believes that the slab can be treated as an isotropic one and designed as the class III PC. Many kinds of the PCC Form Panels and their applications to both civil and architectural engineering constructions are shown in this paper. New trials to be done are also proposed by the author.

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In Onohara of Osaka Minou city, double stratified hyperbolic PC tank (diameter=14.426~20.008m, height=39.60m, effective capacity; heigh section=2000m³, low section=4000m³) was constructed. It is positively attach importance to consider senic influence and environment for around inhabitant, and structural remarkable point is that PC wall by post-tensioning system was computerized constructed by slipform method. This papers are writed the following points in this tank construction. 1) standard plan of outside view of tank. 2) abstract of structural design and construction of side wall. 3) accuracy control and quality control of side wall by slipform construction.

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The concrete volume used in the construction work of this building exceeds 100000cu.m., and many kinds of concrete have been used. In order to complete this large-scale concrete work within the prescribed construction period, it was necessary to obtain ready-mixed concrete from several concrete plants. Therefore, it was important to insure homogeneity among the concrete obtained from different manufacturers. To cope with this problem, such countermeasures were taken as setting up the technical committee, introducing full-time consultants, and adopting central control system by a specially established quality control team. Besides, special consideration for easy concrete conveying by pump was necessary since this building is multi-storied with the height being 60m above the G. L., Furthermore, external precast concrete cladding were designed to be used also as permanent forms for concrete walls which means inspection of the outer surface of the walls after depositing is impossible. Then it was necessary than usual to place concrete densely and secure sufficient consolidation. Aa a means of solving these problems, superplaticizer and external vibrater were utilized throughout this construction work. This paper describes the planning and the actual execution process of the construction.

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