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许多工程技术人员一直把40MPa抗压强度的混凝土看作是高强度混凝土。可是,1988年夏,一种120MPa现场浇筑混凝土在西雅图用于位于第2联合广场的52层建筑的基柱;同年,100MPa的混凝土用于建造世界上最高混凝土建筑基柱。在这一领域美国并不是独一无二的,1984年在蒙特利尔的La Laurentienne大厦用90MPa的混凝土浇筑了一个试验柱;1987年竣工的多仑多市的Scotia广场建筑使用了平均抗压强度为93MPa的混凝土。由于高性能混凝土具有高强度特性,在上述所有用途中都使用了高性能混凝土,与此同时,高性能混凝土在不仅要求高强度而且要求耐久性的一些领域上的应用也得到了发展;例如在温和环境中或恶劣的冻融条件下用非引气混凝土建造海上平台和桥梁。对于大多数专业人员来说,高性能混凝土总是和大型土木工程项目联系在一起的,但也有许多高性能混凝土用来解决日常问题的情况,如麦当劳餐厅的混凝土门厅的重建。在详细讨论高性能混凝土的特性之前,先解释一下抗压强度是如何迅速达到几年前还是不可思议的水平的。然后说明为什么一旦专业人员、建筑师、设计师和业主意识到高性能混凝的结构优点以及它优越的耐久性以后,高性能混凝土的应用同样会迅速推广开来。
Many engineers and technicians have always considered 40 MPa compressive strength concrete as high-strength concrete. However, in the summer of 1988, a 120 MPa cast-in-place concrete was used in Seattle for the basement of the 52-story building at 2nd Union Square; the same year, 100 MPa of concrete was used to build the tallest concrete building foundation in the world. The United States is not unique in this area. In 1984, a test column was built with 90 MPa of concrete in the La Laurentienne building in Montreal; the construction of the Scotia Square building in Dorendo, which was completed in 1987, used concrete with an average compressive strength of 93 MPa. . Because high-performance concrete has high strength properties, high-performance concrete has been used in all of the above applications. At the same time, high-performance concrete has been developed in applications that require not only high strength but also durability. For example, Use non-air-entraining concrete to construct offshore platforms and bridges in mild environments or under harsh freezing and thawing conditions. For most professionals, high-performance concrete is always associated with large-scale civil engineering projects, but there are also many cases where high-performance concrete is used to solve day-to-day problems, such as the reconstruction of concrete halls in McDonald’s restaurants. Before discussing the properties of high-performance concrete in detail, first explain how the compressive strength quickly reached an incredible level a few years ago. Then explain why once the professional, architect, designer and owner realize the structural advantages of high-performance coagulation and its superior durability, the application of high-performance concrete will also be rapidly promoted.