箕江大桥的惨案 ,钱塘江二桥的巨大损失 ,湖南民屋的倒塌等建筑工程质量事故时有发生 ,越来越引起人们对工程质量问题的关注。而在工程质量中 ,砼的质量又占主要地位。作为评定砼强度的标准试块 ,由于多种原因用其代表实际结构的混凝土的真正质量 ,可靠性不是很准确。在北美一? The tragedy of the Jiangyi Bridge, the huge loss of the Second Bridge of the Qiantang River, the collapse of Hunan houses and other construction quality accidents have occurred from time to time, causing more and more people’s concern about the quality of the project. In the project quality, the quality of concrete and occupy the main position. As a standard test block for assessing concrete strength, the true quality of the concrete representing the actual structure for a variety of reasons, the reliability is not very accurate. In North America?