聚乳酸表面包裹对氧化钙膨胀性能提升的影响

发布时间：2018-02-04 21:49

本文关键词： CaO膨胀剂表面包裹聚乳酸膨胀性能　出处：《新型建筑材料》2017年09期 　论文类型：期刊论文

【摘要】：利用聚乳酸(PLA)表面包裹改性CaO膨胀剂,采用约束变形测试方法和改进的双圆环方法,系统研究了0.5%、1.0%和2.0%PLA包裹改性CaO对约束密封条件下水泥净浆、砂浆及混凝土膨胀性能的影响。结果表明:相比未改性CaO膨胀剂,PLA包裹改性后CaO膨胀率明显提升,且随着包裹率增加膨胀率增幅扩大;相比于掺未改性CaO膨胀剂的净浆、砂浆和混凝土,掺PLA包裹率为2.0%的CaO-PLA膨胀剂可使水泥净浆和砂浆28 d膨胀率分别提高27.4%和17.6%,混凝土密封养护和水养膨胀率分别提高51.1%和32.4%;砂浆膨胀应力40 h提高了45%。
[Abstract]:The modified CaO expander was modified by polylactic acid lactic acid (PLA) surface, and 0.5% was systematically studied by using the constraint deformation test method and the improved double ring method. The effects of 1.0% and 2.0 PLA-coated modified CaO on the expansive properties of cement mortar, mortar and concrete under confined sealing conditions were investigated. The results showed that the modified CaO expander was better than that of unmodified CaO. After the modification of PLA, the expansion rate of CaO was obviously increased, and the expansion rate increased with the increase of encapsulation rate. Compared with unmodified CaO expansion agent, mortar and concrete. The expansion ratio of cement mortar and mortar increased by 27.4% and 17.6% in 28 days, respectively, when the CaO-PLA expander with PLA entrapment ratio of 2.0% was used. The concrete seal curing and water swelling ratio were increased by 51.1% and 32. 4 respectively. The expansion stress of mortar increased by 45% for 40 h.
【作者单位】：高性能土木工程材料国家重点实验室(江苏省建筑科学研究院有限公司);江苏苏博特新材料股份有限公司;
【基金】：国家自然科学基金项目(51408275) 国家“973”计划项目(2015CB655105)
【分类号】：TU528
【正文快照】： 由于水泥水化产生收缩形成拉应力,导致混凝土浇筑后极易开裂,从而严重影响了混凝土结构的耐久性[1-2]。利用膨胀剂产生的体积膨胀实现补偿收缩是土木工程中最常用的手段之一[3-4]。氧化钙(Ca O)膨胀剂因需水量小、膨胀能大等优点,是当前工程应用最广泛的一类膨胀剂[5-6]。Ca

【相似文献】