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本文从级配理论上对埋块石混凝土进行了比较详细的论述;同时对块石的埋石率、质量和经济效果等问题,也进行了一些探讨。这些问题的研究,对今后改进混凝土埋块石的施工工艺、选择合理的埋石率、提高块石混凝土质量是有一定帮助的。合理选择块石混凝土的埋石率,是一个复杂的问题,它不仅与混凝土骨料级配理论根据有关,同时也与混凝土结构物种类、工程的部位、块石混凝土的施工工艺及施工组织等具体情况有关。本文以级配理论为基础,根据一些工程实际所采用的埋石数字,提出今后埋石率的控制指标,可供各工地参考。但由于过去我国工程中所采用的埋石率是否合理,本文缺乏更深入的分析,以及其理论的分析与实际情况还有出入,所以这些指标具体到每个工程是否都适用,还有待进一步研究。关于块石混凝土的质量问题,本文对与质量有关的几个因素进行了分析,初步得出:在完善的施工条件下,块石混凝土与细骨料混凝土比较,具有抗压强度高而抗拉强度低的特点。这些分析有助于块石混凝土施工中改进施工方法,防止由于施工操作不当而形成的弱点。但块石混凝土的质量问题,受施工因素影响很大,非小规模试验所能完全反映;同时在试验时所采用的一般试块,亦难完全代表实际情况;因此,本文对于混凝土埋块石后不同抗渗性能的影响的试验方法,以及全面地鉴定块石混凝土的质量指标,亦须进一步研究。关于埋块石的经济效果问题,本文从混凝土的配合比分析中,得出混凝土中胶凝材料用量随着混凝土骨料粒径增大而减少的关系,提出埋块石对节约水泥的效果,只有在细骨料混凝土中最为显著的结论。这些分析有助于在今后混凝土工程中,根据不同情况,找出合理埋石率与最合理混凝土骨料级配之间的关系,从而求得最大的节约效果。但是,混凝土埋石的经济效果,除应从节约水泥、增加混凝土容重和降低坝体绝热温升等方面考虑外,还应结合当地自然条件、施工水平和施工条件等多方面进行综合考虑。
In this paper, graded rock concrete is discussed in detail in terms of grading theory. At the same time, some problems such as the burial rate, quality and economic effect of stone are also discussed. The research of these questions will help to improve the construction technology of buried concrete blocks, select reasonable burial rate and improve the quality of block concrete. It is a complex problem to reasonably choose the burial rate of block concrete, which is not only related to the theoretical basis of aggregate gradation of concrete, but also to the types of concrete structures, the parts of the project, the construction technology and construction organization of block concrete Specific circumstances. Based on grading theory, according to the number of burial stone used in some engineering practice, this paper puts forward the control index of burial rate in the future, which can be used for reference of every site. However, due to the reasonable burial rate adopted in our country’s engineering in the past, this article lacks more in-depth analysis, and its theoretical analysis and actual situation are different, so these indicators are specific to each project are applicable, remains to be further studied . As for the quality of block concrete, this paper analyzes several factors related to quality, and initially concludes that: under the perfect construction conditions, the block concrete has the characteristics of high compressive strength and tensile strength Low intensity characteristics. These analyzes help to improve the construction method in block concrete construction and prevent weaknesses caused by improper construction operations. However, the quality of block concrete is greatly affected by the construction factors, which can be completely reflected by the non-small-scale test. At the same time, the common test blocks used in the test can hardly completely represent the actual situation. Therefore, After the different impermeability of the test methods, as well as a comprehensive assessment of the quality of concrete block stone, also need further study. With regard to the economic effect of embedded rock, this paper draws the conclusion that the amount of cementitious material in cement decreases with the increase of aggregate size. The effect of buried rock on the cement conservation is proposed. Only the finest aggregate concrete in the most significant conclusion. These analyzes will help to find out the relationship between the reasonable burial ratio and the most reasonable aggregate gradation of concrete in different concrete projects in future so as to obtain the maximum saving effect. However, the economic effects of concrete burial should be considered in aspects of saving cement, increasing the bulk density of concrete and lowering the thermal insulation temperature of dam, etc., and should be comprehensively considered in combination with local natural conditions, construction level and construction conditions.