橡胶粉嵌锁密实水泥混凝土研究

发布时间：2018-04-23 22:25

本文选题：橡胶粉 + 水泥混凝土　；参考：《长安大学》2014年硕士论文

【摘要】：针对日益增加的废旧橡胶不仅带来了环境压力，同时会造成资源浪费等问题，结合嵌锁密实水泥混凝土粗集料骨架结构的优点，采用橡胶粉等体积替代砂，本研究提出了橡胶粉嵌锁密实水泥混凝土，以期克服普通水泥混凝土因为橡胶粉的掺加而造成的强度大幅衰减等问题。从橡胶粉的表面改性、橡胶粉掺量、纤维掺量、砂率和水灰比对橡胶粉嵌锁密实水泥混凝土的强度和韧性进行分析，确定混凝土的配合比，为橡胶粉嵌锁密实水泥混凝土的推广应用提供依据。通过橡胶粉的宏观亲水性试验和扫描电镜（SEM）表面微观试验表明，橡胶粉经过改性处理，微观结构得到改善、亲水性增强；利用SEM图，对比分析不同龄期下水泥净浆与橡胶粉（改性和未改性）及纤维等基体材料的微观图表明，橡胶粉经过表面处理改善了其与水泥石的界面粘结状况，纤维与水泥石粘结紧密。通过不同因素对RICC混凝土的强度和韧性影响分析，改性橡胶粉RICC混凝土优于未改性橡胶粉RICC混凝土，随着橡胶粉掺量增加，抗压强度下降，抗弯拉强度和应变能密度呈抛物线性变化，弯拉应变在7天龄期时达到最大；随着纤维掺量增加，抗压强度、抗弯拉强度和弯拉应变呈抛物线形变化，应变能密度的变化趋势不同；随着砂率增大，强度、弯拉应变和应变能密度呈抛物线形变化；随着水灰比增大，强度递减，，弯拉应变和应变能密度抛物线形变化。通过方差分析，并结合强度和韧性试验分析，确定了混凝土的最终配合比为：橡胶粉体积掺量为15%、纤维体积掺量为0.8%、砂率为0.32、水灰比为0.38，改性橡胶粉的效果优于未改性橡胶粉。路用性能试验结果表明，橡胶粉嵌锁密实水泥混凝土强度能够满足中等交通等级要求，混凝土的耐磨性、干缩性、抗冻性和抗疲劳性能较普通水泥混凝土有较大提高。
[Abstract]:In view of the increasing waste rubber not only bring environmental pressure, but also lead to waste of resources, combined with the advantages of interlocking dense cement concrete coarse aggregate skeleton structure, rubber powder and other volume instead of sand, In this study, rubber powder interlocking dense cement concrete is put forward in order to overcome the problem of strength attenuation caused by the addition of rubber powder in ordinary cement concrete. Based on the surface modification of rubber powder, the content of rubber powder, fiber content, sand ratio and water-cement ratio, the strength and toughness of cement concrete with rubber powder interlock are analyzed, and the mix ratio of concrete is determined. It provides the basis for the popularization and application of rubber powder interlocking dense cement concrete. The macroscopical hydrophilicity test and scanning electron microscope (SEM) surface microcosmic test of rubber powder show that the microstructure of rubber powder is improved and the hydrophilicity is enhanced by the modification of rubber powder. The micrographs of cement paste, rubber powder (modified and unmodified) and matrix material such as fiber at different ages show that the surface treatment of rubber powder improves the interfacial bond between cement paste and cement stone, and the fiber is tightly bonded with cement stone. According to the analysis of the influence of different factors on the strength and toughness of RICC concrete, the modified rubber powder RICC concrete is superior to the unmodified rubber powder RICC concrete, and the compressive strength decreases with the increase of rubber powder content. The flexural tensile strength and strain energy density changed parabola, and the flexural strain reached the maximum at the age of 7 days, and with the increase of fiber content, the compressive strength, the flexural tensile strength and the bending tensile strain showed parabola shape. The variation trend of strain energy density is different; with the increase of sand rate, the flexural strain and strain energy density change in parabola shape, and with the increase of water-cement ratio, the strength decreases, and the bending strain and strain energy density change parabola. Through variance analysis, combined with strength and toughness test, the final mix ratio of concrete is determined as follows: the volume of rubber powder is 15, fiber volume is 0.8, sand ratio is 0.32, water cement ratio is 0.38, the effect of modified rubber powder is better than that of unmodified rubber powder. The results of road performance test show that the strength of cement concrete with rubber powder interlock can meet the requirements of medium traffic grade, and the wear resistance, dry shrinkage, frost resistance and fatigue resistance of concrete are greatly improved than that of ordinary cement concrete.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

【参考文献】