Study On The Construction Technology Of Mass Concrete Pile Caps Casting By One Time

The construction of mass concrete in bridge engineering, both at home and abroad, mostly adopts segmental construction method. But this method may produce potential quality problems of the segment connections, the construction processes are very complicated and the construction period may be about 10 days longer than casting-concrete-by-one-time method, it also increases construction cost. The duration of the No.l Bridge of Comedian Industrial Park is limited and the mass concrete of main piles, which located in the bad sea environment, has the higher resistance requirement of chloride infiltration. The temperature stress of pile cap, the model of which has 15690 nodes and 13346 elements, is calculated by MIDAS/CIVIL programmed. In order to avoid temperature cracks, Norm of Highway and Bridge Construction Technology(JTJ041-2000) requires that the temperature difference in the construction of mass concrete should not be greater 25℃. The calculation results show that certain insulation measures can meet the requirements. The study on key technologies of mass concrete construction is in the engineering background of temperature-control technologies and preventive measures of high-performance concrete cracks. Under the guarantee of engineering quality, this method can speed up the project schedule, reduce construction costs and provide the construction experience for future similar projects.This study analyses the theory of proportion of concrete, temperature control, concrete performance, temperature stress and argues the engineering reasonability and economy. Under the condition of detail construction technology plans, technical disclosure for construction workers, strict control of construction processes and monitoring the temperature, the construction results show that temperature cracks do not exist in the mass concrete. Thus, the practice prove that the plan of casting mass concrete by one time is feasible.