水泥乳化沥青砂浆质量问题的原因分析及预防

研究目的:高速铁路建设中水泥乳化沥青砂浆被用作轨道板与混凝土底座板之间的弹性垫层,其性能对轨道结构的平顺性、耐久性、列车运行的舒适性与安全性均有重大影响,是高速铁路建设的关键工程结构之一。由于对其施工经验的缺乏,在实际施工过程中对工艺工法掌握不当以及各种外界环境条件的影响,使水泥乳化沥青砂浆垫层在凝结硬化过程中容易产生各种质量缺陷,从而破坏其对轨道板及底座板的粘接力,因此对其产生质量问题的原因进行分析和采用有效措施预防很有必要。研究结论:通过某高速铁路CRTSII型板式无砟轨道水泥乳化沥青砂浆垫层施工实例,对CRTSII型板式无砟轨道水泥乳化沥青砂浆垫层施工中常见的灌注后在板和砂浆的结合处出现微缝隙或在局部出现砂浆不饱满、分层现象;灌注后表面出现大量的微小气泡、较大的气泡、上下连通的气泡以及灌注后水泥乳化沥青砂浆垫层析出沥青颗粒的常见质量问题进行原因分析,总结提出从轨道板封边工艺、灌注工艺、搅拌工艺、原材控制等方面给出了具有很强操作性和针对性的预防措施,可使其施工质量得到较大程度的改善,给类似工程施工提供借鉴。

Analysis of Cause for Quality Problems of Cement Emulsified Asphalt Mortar and Prevention

Research purposes: In high-speed railway construction,the cement emulsified asphalt mortar is used as the elastic cushion between the track slab and the concrete base plate and it is one of key engineering structures,so its property is crucial to the regularity and durability of the track structure and to the comfortableness and security of train.The various quality defects may happen in the course of hardening of the cushion of the cement emulsified asphalt mortar to destroy the cohering property between the track slab and rail base plater because of a little working experience,the improper operation and the impact of the external environment.Therefore,it is necessary to analyze the cause for the quality defects and take the effective measures. Research conclusions:Based on the construction practice of cement emulsified asphalt mortar cushion for a CRTSII slab ballastess track of one high-speed railway,the analysis is made for the causes for the common problems after pouring in the course of construction of,namely,the micro cracks happen in the joint area between the slab and the mortar or the mortar is not full and slices in some areas,and a large number of the tiny bubbles,the larger bubbles,the bubbles of connecting each other from top to down happen and the asphalt bead separate out.The relative measures are presented from the fields of the edge banding technique for the track slab,the pouring technique,the mixing technique and the control of raw materials to improve the construction quality and it can be as the reference to the similar works.