【摘 要】
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As for modem high performance precast concrete, the use of early strength water-reducers is the main method to improve the early strength, shorten the steam
【机 构】
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Beijing University of civil engineering and architecture, 100044,Beijing, China
【出 处】
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The 14th International Congress on the Chemistry of Cement (
论文部分内容阅读
As for modem high performance precast concrete, the use of early strength water-reducers is the main method to improve the early strength, shorten the steam curing time, speed up the turnover rate, reduce the amount of cement and improve economic efficiency.Early-strength water-reducers BTC300 with sulfonic acid groups and amide groups which is synthesized at room temperature has some significant functions such as high water reduction rate, and can also significantly improve hydration rate.Compressive strength of C40 precast concrete with water-reducers BTC300 can reach 56% of Design strength after ld standard curing.The compressive strength of C50 grade precast concrete segments can reach 60% of the design strength after 12h steam curing at 40 ℃, and after 8h Steam curing at 60 ℃,it can reach 74 % of design strength, which shows a significantly performance of earlier strength.
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