低温套筒灌浆料试验研究

发布时间：2018-09-03 13:09

【摘要】：装配式建筑已进入快速发展期,为了保证装配式建筑的整体性及构件连接的强度,需要对预制构件钢筋套筒进行注浆连接。低温套筒灌浆料是适宜在寒冷气候条件下使用的灌浆材料,其主要目的是加快低温环境下的水泥水化速度。通过引入复合水泥的概念,研究了普通硅酸盐水泥、高铝水泥、硫铝酸盐水泥复合使用的特性,进而以复合水泥为水泥凝胶材料,根据探索性试验结果确定了基本配比:胶砂比为1.0,水胶比为0.28。利用基本配比进行矿物掺合料的单掺试验和正交试验,试验研究结果表明,硅灰掺量为4%时效果最好,掺入适量石膏有利于减小水泥收缩,有微膨胀的效果。在单掺石膏试验中大致确定其用量范围为11~13%。将石膏与同样具有缓凝、促凝作用的酒石酸、碳酸锂进行正交试验,得到的最优组合为:石膏掺量:12%、酒石酸掺量:0.16%、碳酸锂掺量:0.12%。掺加防冻剂,可以降低冰点,促进水泥水化。试验开始选取了硝酸钠、甲酸钙、硫酸钠作为防冻剂,进行单掺和正交试验。正交试验发现甲酸钙、硫酸钠对流动度影响很大,无法满足要求。最后选择对流动度影响最小的硝酸钠作为防冻剂,其最优掺量为0.4%。通过试验优化,最终确定低温套筒灌浆料的配比为:普通硅酸盐水泥(PO 52.5)占复合水泥的70%、高铝水泥占复合水泥的20%、硫铝酸盐水泥占复合水泥的10%,硅灰占胶凝材料的4%,石膏掺量占胶凝材料的12%,胶砂比为1∶1,用水量占胶凝材料的28%,酒石酸掺量为0.16%,碳酸锂掺量为0.16%,硝酸钠掺量为0.4%,适量聚羧酸型减水剂。根据具体使用要求研制出P-1和P-2两种低温套筒灌浆料,并对其竖向膨胀率、温度影响、长期强度、氯离子含量进行试验。试验表明,各方面性能均可满足相关标准要求。低温套筒灌浆料的成功研制,使钢筋套筒注浆在冬季及寒冷地区施工成为可能,大大简化冬季施工工序,节省成本。有利于装配式建筑在寒冷地区的推广。
[Abstract]:The prefabricated building has entered a period of rapid development. In order to ensure the integrity of the assembly building and the strength of the member connection, the grouting connection of the prefabricated steel bar sleeve is needed. Low temperature sleeve grouting material is suitable for use in cold climates, and its main purpose is to accelerate the hydration rate of cement in low temperature environment. By introducing the concept of composite cement, the characteristics of common Portland cement, high alumina cement and sulphoaluminate cement are studied, and the composite cement is used as cement gel material. According to the result of exploratory test, the basic ratio is determined: the ratio of cement to sand is 1.0, and the ratio of water to binder is 0.28. The single admixture test and orthogonal test of mineral admixture with basic ratio were carried out. The experimental results showed that the best effect was obtained when the amount of silica fume was 4, and the addition of proper amount of gypsum was beneficial to reduce the shrinkage of cement and have the effect of slight expansion. In the test of single gypsum, the dosage range is approximately determined to be 1113%. The optimum combination of gypsum and tartaric acid and lithium carbonate, which has the same retarding and coagulating effect, is obtained by orthogonal experiment. The optimum combination is: gypsum content: 12: 12, tartaric acid content: 0.16%, lithium carbonate content: 0.12. The optimum combination is: gypsum content: 12%, tartaric acid content: 0.16%, lithium carbonate content: 0.12. The addition of antifreeze can reduce the freezing point and promote the hydration of cement. Sodium nitrate, calcium formate and sodium sulfate were selected as antifreeze at the beginning of the experiment. Orthogonal test showed that calcium formate and sodium sulfate had great influence on fluidity and could not meet the requirements. Finally, sodium nitrate, which has the least effect on fluidity, is chosen as antifreeze, and the optimum dosage is 0.4. By experimental optimization, Finally, the ratio of low temperature sleeve grouting material is determined as follows: ordinary Portland cement (PO 52.5) accounts for 70% of composite cement, high aluminum cement accounts for 20% of composite cement, sulphoaluminate cement occupies 10% of composite cement, silica fume accounts for 4% of cementing material, gypsum content accounts for 20% of composite cement, silica fume accounts for 4% of cementing material, and gypsum content accounts for 20% of composite cement. The ratio of cement to sand is 1: 1, the water consumption is 28%, the amount of tartaric acid is 0.16, the amount of lithium carbonate is 0.16 and the amount of sodium nitrate is 0.4, the amount of polycarboxylic acid type water reducer is moderate. Two kinds of low temperature sleeve grouting materials P-1 and P-2 were developed according to the specific application requirements, and the vertical expansion ratio, temperature effect, long-term strength and chloride ion content were tested. The test results show that all aspects of the performance can meet the requirements of relevant standards. The successful development of low temperature sleeve grouting material makes it possible to construct reinforced sleeve grouting in winter and cold area, greatly simplifies the construction procedure in winter and saves cost. It is propitious to popularize prefabricated buildings in cold areas.
【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU578

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