冬季低温对CRTSⅠ型CA砂浆质量影响研究
Influences of low temperature on CA mortar in winter

针对冬季CRTS(china railway track system)Ⅰ型水泥乳化沥青(cement and emulsified asphalt, CA)砂浆施工,研究低温环境对CA砂浆性能的影响,经温度监测和揭板检查,比选温控措施。研究结果表明:长三角地区冬季施工现场存在-5 ℃~5 ℃的温度环境,在此环境中CA砂浆强度发展缓慢,灌入板腔的CA砂浆边缘会产生孔洞病害;在棉被覆盖保温措施条件下,无加热源时,板下砂浆温度随环境变化而小幅波动,灌注口砂浆断面有粗砂下沉趋势,但未引起分层;有加热源时,板下砂浆温度逐渐升高,揭板断面均匀,符合正线施工要求。
In this paper, influences of low temperature on the performance of CA mortar were studied, and temperature control measures were compared and selected by temperature monitoring after pouring CA mortar and mortar assessment after removing slab track, the results show that winter environment temperature of construction site is lower and ranges from -5 ℃ to 5 ℃ in Yangtze river delta area. Under this temperature conditions, the early strength of CA mortar develops slowly, and some large pores distresses appear in the edge of CA mortar under the track slab. When using cotton quilt coverage, the temperature of CA mortar under slab changes with the environment by fluctuation within a narrow range, cross section of mortar inlet shows coarse sand has an subsidence tendency without producing delamination; under the conditions of cotton quilt coverage and heat source, the temperature of CA mortar under slab raises gradually, with the environment by fluctuation within a narrow range, mortar assessment reveals good cross section uniformity by removing track slab, and it is completely in conformity with the technology requirements