近20年来,对混凝土力学行为的研究表明,混凝土的破坏是内部裂缝的产生、扩展、连通以至失稳的过程;混凝土的强度、变形性能以及耐久性等也和内部孔缝的发展与变化密切相关。不连续点就是表征混凝土在载荷下,内部稳定裂缝(当荷载增加,裂缝扩展;若保持应力水平恒定,则裂缝就停止扩展)扩展阶段的起始点(裂缝扩展包括裂缝数目增加和裂缝扩大)。此时,混凝土内部较严重的裂缝开始发生,即 In the past 20 years, studies on the mechanical behavior of concrete have shown that concrete failure is the process of generation, expansion, and communication and even instability of internal cracks; the strength, deformation properties, and durability of concrete are also closely related to the development and change of internal seams. Related. The discontinuity is the starting point of the expansion phase, which characterizes the concrete under load, and the internal stable cracks (when the load increases, the cracks expand; if the stress level is kept constant, the cracks stop expanding). (The crack extension includes an increase in the number of cracks and an increase in cracks). At this time, the more serious cracks in the concrete began to occur, that is,