【作者】 张兵兵；

【导师】 陈昌国；

【作者基本信息】 重庆大学 ， 化学， 2012， 硕士

【摘要】 CA砂浆是板式无碴轨道的核心技术之一，它被填充在轨道板和底座之间，起到支撑和调整轨道板，吸收高速列车对轨道的荷载和隔绝对基体的震动破坏的作用。CA砂浆由水泥、细骨料、沥青乳液、水以及多种添加剂等原材料组成，通过水泥的水化硬化和沥青的胶结而成的一种有机-无机复合材料，兼具水泥刚性和沥青弹性的特点。本文以降低砂浆成本为目的，通过较廉价的废橡胶粉代替部分乳化沥青改性CA砂浆，研究橡胶粉的加入对砂浆的制备和性能的影响。结果表明：（1）橡胶粉的粗糙的表面、亲油性以及不敏感的时温效应是其对CA砂浆性能造成影响的根本原因；（2）加料顺序对CA砂浆早期强度有影响，且两种顺序各有特点；（3）含气量、膨胀率会随废橡胶粉含量的增加而增大，分离度则会随着废橡胶粉含量的增加而减小，但CA砂浆的工作性能会随着废橡胶粉含量的增加而变差；（4）CA砂浆的力学性能受橡胶粉的影响，其早期抗压强度会随着废橡胶粉含量的增加而减小，而28天抗压强度以及弹性模量则逐渐增大；（5）水泥-沥青比是影响CA砂浆的抗压强度的主要因素之一，比值越大，抗压强度越大，比值越小，抗压强度越小；（6）不论废橡胶粉含量多少，改性CA砂浆的抗压强度都随着温度的升高而减小，随着加载速率的升高而增大，弹性模量随着温度的升高而变小；（7）废橡胶粉含量越高，改性CA砂浆对温度越不敏感，加载速率对CA砂浆抗压强度的影响越不明显，即其时间稳定性越好，说明橡胶粉可以改善CA砂浆的时温效应。CA砂浆在200倍显微镜下的照片说明橡胶粉能够改善材料中无机相和有机相的分布，从而提高材料的均质性，并且使体系中自由沥青大幅减少，改善材料的时温依赖性。成本分析表明，橡胶粉每代替5%的乳化沥青，可节约2.6%的成本，这说明废橡胶粉改性CA砂浆是经济可行的，达到了预期的目标，也为以后这方面的研究提供了依据。更多还原

【Abstract】 CA mortar is one of the key technologies of slab ballastless track, which issandwiched between two slabs and serves the purpose of supporting and adjusting ofslab track, absorbing the load of high-speed train, isolating from vibration damage. CAmortar is composed of cement, fine aggregate, asphalt emulsion, water and a variety ofadditives and is a high performance organic-inorganic composite material which has thecombined merits of high strength of cement and good elasticity of asphalt.CA mortar is modified by waste rubber power which takes the place of emulsifiedasphalt to reduce the mortar cost, and the performance is studied in this paper. Theresults have indicated that:(1) the root cause of influencing the performance of CAmortar is the rubber powder that is rough surface, lipophilic and insensitive to thetime-temperature effect.(2) The early strength of CA mortar would be affected byfeeding order, and the two kinds of order have their own characteristics.(3) With theincrease of the rubber power content, the work performance of CA mortar has becomepoor; gas content, expansion ratio increased, but resolution would be decrease.(4) Themechanical properties of CA mortar also have been influenced by rubber powder. Theinitial compressive strength of CA mortar has decreased with the increasing of wastedrubber powder content, but the strength increased after28days.(5) Cement-Asphaltratio is one of the main influence factors on the compressive strength of CA mortar. Thecompressive strength is proportional to the ratio.(6) The compressive strength of CAmortar has decreased with the rising of temperature and increased with the increasing ofloading speed, and the elastic modulus has decreased with the rising of temperatureregardless of the content of rubber power.(7) The content of rubber power has beenhigher, the sensitiveness of CA mortar to temperature has been lower and the influenceof loading rate on the compressive strength of CA mortar has been more unobvious.These mean the stability of CA mortar with rubber power has been better and thetime-temperature effect of CA mortar can be improved by rubber powder.The micrographs of CA mortar show that the distribution of inorganic phase andorganic phase in CA mortar can be improved by the rubber powder, thereby thehomogeneity of CA mortar is increased, and the content of free asphalt in CA mortar isreduced. Consequently, the time-temperature effect of CA mortar can be improved byrubber powder. Cost analysis shows that every5%of emulsified asphalt is replaced by the rubber powder,2.6%of the cost of CA mortar will be saved. This indicates that CAmortar is modified with the waste rubber powder is economically feasible. Theseprovide a basis for future research in this field.更多还原