Research On The Temperature Controlling Measures In Certain Roller Compacted Concrete Gravity Dam

The problems of thermal stress and the temperature controlling measures have great significance in the mass concrete project. Roller compacted concrete dam (RCCD) which resembles normal concrete dam also have crack problems arising by thermal stress. The thermal stress of RCCD have different characteristics with normal concrete dam, which should been considered in, for that the effective temperature controlling measures guaranteeing the safety of dam can be made.In this paper, the 3-D finite element relocating mesh method is used to calculate the temperature field and the thermal creep stress field of spillway dam and mid level outlet dam in certain roller compacted concrete gravity dam, sensitivity analysis have been down with different parameters, such as placing temperature, the location of cooling pipe, cooling temperature, time for water supply, ascended-layer of concrete, intermissive time and different placing time, and the commendatory construction scheme have been put forward in such analysis; according by the test result on the two scheme of concrete aggregate combination (basalt as coarse aggregate and limestone as fine aggregate, basalt as coarse aggregate and basalt as fine aggregate), simulation analysis on temperature field and thermal creep stress field of the commendatory construction scheme have been down, and analysis have also been down on temperature field and thermal stress field of the two different aggregate combination, the result indicates that the spillway dam and mid level outlet dam which adopted these two aggregate combination can both satisfy the require of design crack resistance in concrete, furthermore limestone as fine is better than basalt as fine aggregate; the effect of summer water storage and winter water storage on the temperature field and thermal stress field have been analyzed, comparing with winter water storage, in summer water storage scheme the maximum tensile stress at abnormal concrete in upstream fill is decreased by 0.1～0.3MPa and there are no evidence change of the maximum tensile stress at other parts, which indicate that summer water storage is avail for the crack resistance of upstream fill; according to the simulation calculating result and comparing temperature simulation calculating results and temperature controlling measures of some similarity projects both completed and construction, synthesis appraise have been carried to the design temperature controlling measures of dam, and the temperature controlling measures of this project have been brought forward, all these have great reference value on the design of temperature controlling measures and the optimization of the construction scheme.