CSA膨胀剂对C80高性能混凝土性能影响及膨胀机理研究  

Research of performance and expansion mechanism of the C80 high performance concrete with CSA expansive agent

作　　者：蔺喜强[1] 王栋民[2] 陈雷[2] 霍亮[1] 张涛[1] 

机构地区：[1]中国建筑股份有限公司技术中心,北京101300 [2]中国矿业大学(北京),北京100083

出　　处：《混凝土》2013年第2期91-94,共4页Concrete

摘　　要：研究表明在水灰比为0.5且掺10%CSA膨胀剂的砂浆中,砂浆膨胀性能在7 d时达到最大,其限制膨胀率为0.048 5%。不同CSA膨胀剂掺量的C80混凝土中,膨胀剂掺量越高混凝土早期强度越低,后期强度降幅小。在水化早期,膨胀剂掺量对混凝土限制膨胀率的影响较小,养护龄期14 d时达到限制膨胀率的最大值,较水灰比0.5砂浆的有所推迟且最大值受掺量影响大。膨胀剂的掺加对低水胶比水泥浆体水化早期体系的孔结构有改善作用,体系中钙矾石晶体未能充分生长,多以微针状分布于各个界面层间,体系中未反应的水泥颗粒较多。水化后期胶凝体系硬化后的浆体中包裹着竖条状形貌的钙矾石晶体,凝胶相具有良好的密实性。Studies had shown that the limit expansion of the mortar to achieve the maximum value of 0.048 5% when the mortar cement ratio of 0.5 and add 10% CSA expansive agent.Expansive agent dosage the higher the lower the early strength of concrete,but the latter intensity decrease was relatively small in the C80 high performance concrete.In the early hydration, expansive agent dosage limit the rate of expansion of concrete, curing period 14 d reached the maximum limit expansion,in comparison to the maximum water-cement ratio 0.5 mortar delay, and the maximum value by the dosage effect.CSA concrete expansion agent to improve the role of low water cement ratio the pore structure of cement paste hydration early system, ettringite crystals in the system not fully grown, multi-micro-needle distribution at each interface between layers,the system unreacted cement particles more.Hardening of the cementitious paste wrapped vertical stripe morphology of ettringite crystals, the gelling phase with the density of the hydration reaction in the late.

关 键 词：CSA膨胀剂 高性能混凝土 自收缩 微观结构 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]