高效能减水剂在高强度混凝土工程中的应用与注意事项
2018-11-07塔依尔·喀德尔
塔依尔·喀德尔
摘 要:目前混凝土技术发展的方向是轻质,快硬和高强。由于高强和轻质,快硬密切相关,许多学者认为它的主攻方向是高强。由于高标号水泥的出现,混凝土工艺的改革,以及化学外加剂的应用,使混凝土的平均标号和最高抗压强度不断提高。我国高强度混凝土的含义,以各部门的不同有所区别,例如工程建筑部门以混凝土强度300 kg f/cm2作为分解;水工建筑部门将300 kg f/cm2以上的称高强度混凝土;铁道建筑部门将大于400 kg f/cm2以上的称高强度混凝土。混凝土结构的轻型和高强化,已引起人们的极大兴趣,可以预计到本世纪末混凝土材料不仅是建筑材料使用量最大的,而且仍是有发展前途,应用范围不断扩大的一种材料。
关键词:减水剂;混凝土工程;应用;注意事项
Abstract: The present direction of development of concrete technology is lightweight and fast hard and high strength . Because of high strength and light weight , fast hard closely related , many scholars believe that it is the main direction of high strength . Due to the emergence of high-grade cement , concrete reform process , as well as the application of chemical admixtures , the average grade and the highest compressive strength of the concrete continues to increase. China's high- strength concrete meaning to distinguish the different departments, such as engineering and construction sector with concrete strength 300 kg f/cm2 as decomposition ; hydraulic construction sector will 300 kg f/cm2 or more , said high-strength concrete ; Railway construction sector will be greater than 400 kg f/cm2 or more , said high-strength concrete . Lightweight and high reinforced concrete structures , has attracted great interest , can be expected to the end of the century is not only the amount of concrete largest building materials, but still promising, expanding the scope of application of a material .
Keywords: water reducer; concrete engineering; application; Precautions
1.高強度混凝土的配制及材料要求
配制高强度混凝土的方法有:采用高标号水泥;加压、加压振动或加压真空处理;采用优质高粘着力的活性骨料;采用聚合物;采用高压蒸汽养护;掺用高效能减水剂等。
综合比较上述六种方法,掺高效能减水剂具有使用方便,设备简单和价格低廉等特点,因此,近几年来掺高效能减水剂配制高强度混凝土已被大量使用。
1.1高效能减水剂
当采用高效能减水剂配制高强度混凝土时,减水剂应具备下列条件:
(1)强分散性,减水率大;
(2)增强性能高;
(3)引气性低;
(4)不含氯或微量氯;
(5)不延缓凝结硬化。在掺减水剂的水泥浆体流动度的实验方法中,目前规定的……
