盐-冻融弱化因子胁迫下橡胶粉改性水泥压浆材料试验研究

Experimental Study on Rubber Powder Modified Cement Grouting Material under Salt - Freeze Thawing Weakening Factor

摘要:

选用典型橡胶水泥类脱空修补材料，分别控制龄期（1、3 d）和橡胶粉掺量为0%、5%、10%、15%、20%。以实验数据统计分析为基础，归纳总结在盐-冻融环境下不同龄期、不同掺量的修补材料下动弹性模量、抗压强度、抗折强度和体积膨胀率的弱化趋势。试验结果表明，掺入橡胶粉后，压浆材料各项力学指标具有显著提升，提升效果由优到劣依次为动弹性模量、抗压强度、抗折强度。对于城市主干路而言，应优先选择提高橡胶粉掺量，以确保注浆完成后，路面结构具有较高承载能力。对于交通量较小的城市次干路及以下道路，应优先考虑增加养生时间。在工程实践中，应将橡胶粉掺量控制在12%，以获得最大的工程效果。压浆材料体积膨胀率均控制在3%以内。这表明橡胶水泥类压浆材料在冻融循环作用下，不仅体积膨胀率较好，而且稳定性较高。

Abstract:

A typical rubber-cement void repair material is selected. The control ages are 1d and 3d respectively, and the dosage of rubber powder is 0% and 5%, 10%, 15% and 20%, respectively. Based on the statistical analysis of experimental data, the weakening trend of dynamic elastic modulus, compressive strength, flexural strength and volume expansion rate of repair materials of different ages and different dosages in salt-freeze thawing environment is summarized and analyzed. The test results show that after adding the rubber powder, the mechanical indicators of the grouting material have been significantly improved, and the improvement effect from superior to inferior is dynamic elastic modulus, compressive strength and flexural strength. For urban arterial roads, it should be preferred to increase the dosage of rubber powder to ensure that the pavement structure has a higher bearing capacity after the grouting is completed. For urban sub-trunk roads and roads below with small traffic volume, the priority should be given to increasing the curing time. In engineering practice, the dosage of rubber powder should be controlled at 12% to obtain the maximum engineering effect. The volume expansion rate of the grouting material is controlled within 3%, which shows that the rubber cement grouting material not only has a good volume expansion rate, but also has the good stability under the action of freeze-thawing cycles.