粉煤灰掺量对冲填砂浆结石体性能影响试验研究

发布时间：2018-01-13 23:34

本文关键词：粉煤灰掺量对冲填砂浆结石体性能影响试验研究　出处：《沈阳农业大学》2016年硕士论文　论文类型：学位论文

【摘要】：最近几年,有专家提出冲填砂浆结石筑坝技术,是对浆砌石筑坝技术的一种革新。概括起来即为,利用混合砂浆自身的重力、流动性、冲击力来将事先搅拌好的,按要求配比的流动性混合砂浆灌入事先摊平好的毛石料上,使砂浆自由流入毛石之间的空隙中去,来完成结石体的快速堆砌。此种简单有效的施工方法的工作关键有两个方面：1)为了保证混合砂浆和块石具有良好的整体性能,必须尽可能避免在混合砂浆在冲填过程中产生气泡或留有空隙,保证砂浆和骨料不离析,砂浆可以自由流动在骨料之间的缝隙中,达到冲填密实效果。2)为了满足混合砂浆和骨料块石之间的力学性能和强度大小要求,必须充分保证块石与混合浆的界面具有良好的粘结性。本文通过对堆石体和混合砂浆的各自性能特点以及发挥材料各自的优势,提出了冲填砂浆结实施工技术。改变了原材料的利用方式,必定会对其各方面性能要有新的了解,所以本文对冲填砂浆结石施工技术主要进行了以下几个方面的具体试验。首先进行了冲填砂浆结石施工技术混合砂浆的材料配比试验：在满足胶凝材料总量不变的前提下,通过改变粉煤灰的掺量(0%、20%、30%、40%、60%)和水胶比的情况下,设计出15组试验,其中有3组为不掺和粉煤灰的对照试验。通过对砂浆的基础试验初步总结出粉煤灰掺量和水胶比对混合砂浆性能的影响,从混合砂浆的抗压强度、保水性、以及流动性三方面综合考虑,选出五组符合冲填砂浆结石施工技术性能要求的混合砂浆配合比,其中有一组是不掺和粉煤灰的对比试验。其次选用以上五组混合砂浆的配比,模拟冲填砂浆现场冲入结石体的过程。在实验室内,利用装入块石的玻璃箱来代替室外冲填环境的冲填试验。试验初步证明混合砂浆在堆石体中是可以满足冲填结石要求的。通过试验可以进一步确定强度满足要求、砂浆流动性好、经济的最佳的砂浆配合比。最后选用一组配比进行不同骨料粒径的结实体抗压强度试验,将第8组混合砂浆灌入装有不同粒径块石的尺寸为200mm×200mm×200mm的试模中养护28d形成冲填砂浆结石体,利用WAW-2000D型压力机做结石体的抗压强度试验,分别检测结石体试块的抗压强度。通过本文的研究可以得出如下结论：1)当水胶比为试验所用的三种梯度,粉煤灰掺量为20%、30%、40%、60%其混合砂浆的稠度均满足冲填要求。且当粉煤灰掺量为40%、60%时其试块强度等级小于lOMP,不满足设计强度为10MP以上的要求,暂时不做考虑。2)从砂浆的流动性,抗压强度,保水性,经济因素,环境等方面考虑选择粉煤灰掺量为30%为最优。最优一组砂浆冲填在块石中,形成的结实体强度大约是此砂浆试块强度的1.3倍。3)在粉煤灰掺量相同的条件下,混合砂浆的稠度随着水胶比的增大而变大,混合砂浆的抗压强度随着水胶比的增加呈降低趋势,分层度则逐渐变小；在水胶比相同的条件下,随着粉煤灰掺量的增加,混合砂浆的稠度在不断增大,立方体的抗压强度逐渐减小。4)结实体块石粒径对其强度也稍有影响,粒径越大强度也在变大。
[Abstract]:In recent years, some experts suggested filling mortar stone dam construction technology, is a kind of innovation of technology of masonry dam. To sum up is that liquidity by mixed mortar, the impact force of its own gravity, to advance the well stirred, according to the liquidity ratio requirements of mixed mortar poured into the flat well in advance the hair stone, the gap between the free flow of mortar rubble to pile up quickly to complete the stone body. The key work of this construction method is simple and effective to have two aspects: 1) to ensure that the mixed mortar and stone have good overall performance, must be avoided as much as possible in the mixed mortar in filling production in the process of bubble or gap, ensure the mortar and aggregate segregation mortar can flow freely in the gap between the aggregate, to fill compaction effect of.2) in order to meet the mechanical properties and strength of mixed mortar and aggregate stone Size requirements must be fully guaranteed and stone mixture interface has good adhesion. The advantages of the respective materials of rockfill and mixed mortar and put forward their separate characteristics, fill strong mortar construction technology. Changed the ways of using raw materials, will have a new understanding of it all aspects of performance, so the construction technology of mortar stone hedge fill the main test following the first filling mortar stone construction technology of mixing mortar material ratio test: in order to meet the total amount of cementitious materials at the same time, the content change of fly ash (0%, 20%, 30%, 40%, 60%) and water binder ratio, designed 15 sets of experiments, including 3 group test of mixing coal ash. The basic test of mortar were summarized on fly ash content and water gel mixture Influence of mortar properties, the compressive strength of mixed mortar, water retention, and three aspects of liquidity into consideration, selected five groups meet the performance requirements of filling stone construction mortar mixed mortar, which is a set of experiments not admixture of fly ash. Then the above five groups of mixed mortar the simulation process, filling mortar into the field stone body. In the laboratory test, fill with glass box into the stone to fill in place of the outdoor environment. This experiment demonstrated that mixed mortar can meet the requirements of filling stone in rockfill. The test can further determine the required strength, mortar flow good mix. The optimum economic strong mortar compressive strength test body finally selecting a group of different ratio of aggregate size, the eighth groups of mixed mortar poured into a different size block stone size For filling mortar stone formation maintenance 28d test model 200mm * 200mm * 200mm, using WAW-2000D press do compressive strength test of stone body, were used to detect the stone body compressive strength. Through this study we can draw the following conclusions: 1) when the ratio of the three gradient used for test of water gel and the amount of fly ash was 20%, 30%, 40%, 60% of the mixed mortar consistency can meet the filling requirements. And when the amount of fly ash was 40%, 60% of the block strength is less than lOMP, does not meet the design strength of 10MP the above requirements, temporarily do not consider.2) from liquidity. The mortar compressive strength, water retention, economic factors, environment and other aspects to consider with 30% fly ash is optimal. A set of optimal mortar fill in block stone, fruiting body strength formation is about 1.3 times the mortar test block strength.3) in fly ash under the same conditions. Mixed mortar The consistency with the water cement ratio increases, the compressive strength of mortar mixed with water binder ratio decreased, delamination degree becomes smaller; the water cement ratio under the same conditions, with the increase of fly ash, mixed mortar consistency increasing, the compressive strength of the cube decreased.4) strong body block size on the strength of a slightly larger diameter impact strength is also larger.

【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TV432

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