Low-Temperature Technique Study Of Rolled Asphaltic Concrete Core Wall Of Ni'Erji Water Control Project

The Ni' erji Water Control Project is located in the Nenjiang River, on the border of Molidawa Autonomous County of Inner Mongolia Autonomous Region and Nehe County of Heilongjiang Province. According to planned construction progress the construction of asphaltic concrete core wall shall be executed from April to Octomber. For constructing earth-rock dam with asphaltic concrete core wall in northeast cold area of China, the golden construction season for construction of asphaltic concrete impervious wall of the dam is from May to September. But the main flood period in northeast area is from July to the first ten-day period of September, therefore the atmospheric rainfall is more, the numbers of day for effective construction of asphaltic concrete impervious core wall is less, from January to April and from October to December the mean annual temperature (separately are -22.0℃, -17.3℃, -6.6℃, 4.4℃, 2.8℃, -9.7℃, -19.2℃), all are lower than temperature standard of 5℃ for normal construction day required by Construction Specifications [daily mean temperature for normal construction is not lower 5℃ given by 《Rolled Earth-Rock Dam Construction Specification (SDJ213-83) 》. As a result of that in April and October the numbers of day in which the day temperature is higher than 5℃ are more in the Project Area, only the night temperature is lower than 5℃ even negative temperature, it cause big temperature difference between the day and night and low daily mean temperature, therefor, if the specific measures has been taken on construction of rolled asphaltic concrete impervious corewall in April and October, the number of day for effective construction of asphaltic concrete impervious core wall will raise, the construction strength will be reduced, the construction period of dam can be curtailed and it will create favorable conditions for completion of the Project ahead of time. In this paper it emphatically is introduced that the construction technique studying works of rolled asphaltic concrete impervious core wall under conditions (0~5°C) is carried out on the basis of testing (indoor testing and testing in the Site), the suitable control measures for construction of asphaltic concrete impervious core wall of Ni'erji earth-rock dam has been put forward, and the working time can be prolonged under prerequisite conditions of assuring construction quality. Moreover, by introducing low-temperature construction of rolled asphaltic concrete core wall of Ni1 erji Water Control Project, in this thesis it is made clear that the construction of rolled asphaltic concrete can be still executed in low temperature 0~5°C with taking specific measures, the construction quality can be assured and meets the design requirements. This studying work makes a certain breakthrough in respect of low-temperature construction technique of asphaltic concrete. The low-temperature construction can effectively prolong construction period of rolled asphaltic concrete impervious core wall in cold area and it shall be used for reference and applied to similar project.