设计一个建筑物总是要求它在预定的使用时间内能很好的工作,胜任设计所赋予的任务。但是,定值法设计都是采用设计规范中所规定的混凝土强度值,是一个定值。实际上建筑物在施工后和使用过程中混凝土的强度并不是确定不变的量,而是一种受到施工条件、所在位置、使用时间和环境等多种因素影响的不确定量,即随机变量。通过大量的实测,充分证明了这种随机变量的存在。因此对已有建筑物混凝土强度的鉴定一直是人们非常关心的问题。已有建筑物混凝土强度鉴定需要考虑下面几个问题: Designing a building always requires that it be able to work well within the scheduled time of use and be able to perform the tasks assigned to the design. However, the constant value design is based on the concrete strength value specified in the design specification and is a fixed value. In fact, the strength of concrete after construction and during use is not a definite quantity, but is an uncertain quantity influenced by various factors such as construction conditions, location, usage time and environment, ie random variables. . Through a large number of actual measurements, the existence of such a random variable is fully proved. Therefore, the identification of the concrete strength of existing buildings has always been a matter of great concern to people. Existing buildings concrete strength identification need to consider the following questions: