【摘要】 混凝土大坝在施工期或运行期产生裂缝的现象较为普遍,为了满足工程安全运行的要求,一般对危害较大的裂缝进行灌浆处理。本文提出从以下四个方面对裂缝灌浆效果进行综合评价:(1)通过裂缝的成因、特点和危害性认识,评价灌浆处理原则、采用的嵌缝材料是否满足要求;(2)从灌浆施工工艺和质量控制手段评价裂缝灌浆效果;(3)对灌浆处理后的裂缝采取骑缝取芯样并进行力学性能试验,掌握裂缝灌浆后的实际抗拉和抗渗性能;(4)通过裂缝灌浆前后的三维有限元模拟计算,分析灌浆后混凝土坝整体稳定性、重点部位和裂缝处局部力学性能的差异。最后,以青铜峡大坝电站坝段三大条贯穿性裂缝的灌浆效果评价为例,介绍本评价方法的应用。结果表明:采用本评价方法能对裂缝灌浆效果进行较为科学、客观的评价,并对今后的大坝裂缝处理、评价提供借鉴。更多还原

【Abstract】 It is common that concrete dams occur cracks in construction or operation.In order to operate safely,grouting is always adopted as the treatment for some harmful cracks.In this paper,the four aspects are considered for overall evaluations of crack grouting.First,by the recognition of causes and characteristics as well as the harm of cracks,the grouting principle is examined whether the grouting materials can meet the requirements.Second,the grouting is evaluated from grouting technology and the measures of quality-control.Third,the core samples of grouting obtained along the cracks are tested for mechanics properties so as to get the real behaviors of tensile strength and water-proof.Fourth,by 3D FEM simulation computation of fore-and-aft crack grouting,stability of the whole dam and the mechanics differences of key parts and partial sections of cracks after grouting are analyzed.Finally,the grouting for three big penetrable cracks of Qingtongxia dam is taken for an example to introduce the application of this evaluation,the results show that the evaluations of grouting proposed in this paper can be scientific and objective and can provide the references for crack grouting of other concrete dams and its evaluation.更多还原