关键词: 大体积混凝土;配合比;绝热温升;缓凝剂;温控措施

Abstract: The effects of retarder type, content of fly ash-slag powder composite mineral admixture and PAN fiber on concrete setting time, workability, mechanical properties, adiabatic temperature rise and durability were systematically investigated through the construction of temperature and crack control of 10# main pier pile cap mass concrete in Jiayu Yangtze river highway bridge.Additionally, a kind of C40 pile cap concrete with super retarding and low hydration heat has been successfully cast.Then, Midas FEA finite element method was employed to calculate and analyze the temperature field and stress field of pile cap mass concrete.And a sequence of efficient temperature control measurements including reducing the pouring temperature of concrete, setting up cooling water pipe in a reasonable way and heat and moisture preservation were adopted.It turn out that no harmful cracks occurred in the pile cap mass concrete and its temperature control index met all the requirements of the temperature control standards.

Key words: mass concrete;mix proportion;adiabatic temperature rise;retarder;temperature control measure