基于不同界面剂对第二龄期新老混凝土粘结强度影响的研究

发布时间：2018-05-16 20:07

本文选题：新老混凝土粘结 + 界面剂　；参考：《郑州大学》2016年硕士论文

【摘要】：本文通过对常见三种混凝土进行第二龄期新老粘结试验,选用三种界面剂研究其对于不同种类混凝土的粘结效果及其适用性,首次提出了粘结强度等效系数β,分析了新老混凝土粘结界面在界面剂作用下的水化机理。主要内容和结论如下:(1)选用常见的普通硅酸盐水泥、矿渣水泥、复合型水泥配置C30混凝土作为试验混凝土,选用水泥净浆、掺粉煤灰的水泥净浆和新型材料TG-1固结剂掺水泥净浆作为试验界面剂。通过凝结时间试验确定三种混凝土的初凝终凝时间,从而确定其第二龄期,为新老粘结试验做准备。(2)试验研究了三种界面剂分别用于三种混凝土新老粘结的效果。试验结果表明:水泥净浆界面剂的粘结效果随着其水灰比的增大而增强;掺粉煤灰的水泥净浆对混凝土新老粘结界面强度的影响规律性不强;掺TG-1固结剂的水泥净浆界面剂的粘结效果随着TG-1固结剂掺量的提高而增强。就界面剂适用性来说,普通硅酸盐混凝土新老粘结选用掺50%TG-1固结剂水泥净浆作为界面剂的粘结效果最好,矿渣水泥混凝土新老粘结选用水灰比为0.3水泥净浆作为界面剂的粘结效果最好,复合型水泥混凝土新老粘结选用50%TG-1固结剂水泥净浆作为界面剂的粘结效果最好。(3)为比较不同种类界面剂用于不同混凝土的粘结效果,本文首次提出了粘结强度等效系数β,表示新老混凝土粘结强度与基准试块劈拉强度的比值,即粘结强度的有效性。(4)分析了界面剂作用于新老混凝土粘结界面的水化机理。研究表明:水泥净浆界面剂是通过改善界面过渡层的微观结构来提高新老混凝土的粘结强度,掺粉煤灰和TG-1固结剂的水泥净浆界面剂主要是通过化学作用促进粘结界面的水化反应来提高粘结界面强度。
[Abstract]:In this paper, three kinds of common concrete are tested in the second age, and three kinds of interfacial agents are selected to study the bonding effect and its applicability to different kinds of concrete. The equivalent coefficient of bond strength 尾 is proposed for the first time, and the hydration mechanism of new and old concrete bonding interface under the action of interface agent is analyzed. The main contents and conclusions are as follows: (1) Common Portland cement, slag cement, composite cement with C30 concrete as test concrete, cement paste, Fly ash cement paste and new material TG-1 consolidation agent are used as test interface agent. Through setting time test to determine the initial setting time and final setting time of three kinds of concrete, so as to determine its second age, and to prepare for the new and old bond test, the effect of three kinds of interfacial agents used in three kinds of concrete new and old bond were studied. The experimental results show that the bonding effect of cement paste interfacial agent increases with the increase of water-cement ratio, and the influence of fly ash cement paste on the new and old bond strength of concrete is not strong. The bonding effect of cement paste interfacial agent with TG-1 consolidation agent increased with the increase of TG-1 consolidation agent content. As far as the applicability of interfacial agent is concerned, the new and old bond of ordinary Portland concrete is the best one to use cement paste mixed with 50%TG-1 consolidation agent as interfacial agent. The new and old bond of slag cement concrete is best when the water cement ratio of 0.3 cement paste is used as the interfacial agent. The new and old bond of composite cement concrete using 50%TG-1 cement paste as interfacial agent is the best. In this paper, the equivalent coefficient 尾 of bond strength is presented for the first time. The ratio of the bond strength of new and old concrete to the splitting tensile strength of benchmark concrete, I. E. the validity of bond strength, is proposed for the first time. The hydration mechanism of interface agent acting on the bond interface of new and old concrete is analyzed. The results show that the cement paste interfacial agent can improve the bond strength of new and old concrete by improving the microstructure of interfacial transition layer. The cement paste interfacial agent mixed with fly ash and TG-1 cementing agent mainly promotes the hydration reaction of the bond interface through chemical action to improve the bond interface strength.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU528

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