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This paper deals with the influence of conveyance vibration on compressive strength of specimen of high-strength concrete. In the experiment, six kinds of concretes (water binder ratio is 60% to 20%) were examined. Conclusions are as follows. (1) The conveyance vibration affects compressive strength of specimen. Immediately after production of concrete, conveyance vibration causes strength reduction of specimen. Then, if concrete begins to harden, conveyance vibration will contribute to the improvement in compressive strength. Furthermore, if time passes too much since production of concrete, conveyance vibration will cause strength reduction. (2) Concrete with low water binder ratio is hardly subject to the influence of conveyance vibration. One of the reasons of this is that water and air hardly move in concrete with low water binder ratio. (3) It is not desirable to carry a test specimen immediately after mixing of concrete. Moreover, after time passes very much since mixing of concrete, it is not desirable to carry a test specimen, either.

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Test age and curing method of specimen for manufacturing control of high strength concrete were investigated and following results were obtained. 1) The strength correction value of high strength concrete is small in the order of Ordinary portland cement > Moderate heat portland cement > Low heat portland cement. Moreover, it was necessary to set test age of high strength concrete using Moderate heat portland cement and Low heat portland cement on the day after the 28th. 2) In the case to use portland cement, if strength test is set within 91 days, the strength correction value doesn't reach a big negative value. 3) In the case of binder water ratio is six to seven, even if strength test is set within 91 days, the strength correction value reaches a big negative value. 4) Also in the case with 3), reasonable manufacturing control can be done by the hot water cured specimen.

A45 ・ story RC building ， where pre ・ 。ast cencrete mernbers were ernployed for its outer 丘ame as well as inside colurnns and bearns ， were constuCtion ， and the estirnate equadon of the opcration standard time was examined with its construction data ． As a resu 監 ち the f［) nowing conclusions were obta ed ． 1) In this measuremen ち the installation time of the pre −cast member in the top f監 oor has decreased to 39 ． 4-63 ． 8％ compared with that in the且oor ． 2)In the construction of the high − rise RC building ， the reasoll f () r the reduction in sta置 1ation of th巳 pr巳 ・ cast Golumn and the pre − cast bearn from a lower fioor tO the upper depends on both the imprevement of werke ゼ s capability and the Ghange i 皿 丗 e work di伍 cult ｝ ， ． 3) The change in the 軟) tal mean operation time by repeating work 血 high・ rユ se RC bu 胴 ings can be estimated with 血 e logarithln model ofthe leam 藍 ng engineering ． Howeve ら it is necessary to consider the change in the work di伍 culty for evaluation of the insta 艮 1ation time ofp 鵜 ・ Gast menibers in high − rise RC buildings ．