聚丙烯纤维对桥面铺装轻骨料混凝土性能影响  

Influence of Polypropylene Fiber on the Properties of Bridge Deck Pavement Lightweight Aggregate Concrete

作　　者：刘娟红[1] 宋少民[2] 钟建锋[3] 陈晓芳[3] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]北京建筑工程学院土木与交通工程学院,北京100083 [3]广东省长大公路工程有限公司,广州510620

出　　处：《北京工业大学学报》2011年第5期734-739,共6页Journal of Beijing University of Technology

基　　金：广东省交通厅科技推广项目资助(200904007)

摘　　要：试验研究了聚丙烯纤维对桥面铺装轻骨料混凝土工作性能和强度的影响,探讨了对轻骨料预湿、掺入聚丙烯纤维及钢纤维与开裂时间、开裂面积、裂缝数量的关系.结果表明:聚丙烯纤维的掺入降低了轻骨料混凝土的流动性,当聚丙烯纤维掺量为1.2 kg/m3时,混凝土初始坍落度和扩展度仅为未掺聚丙烯纤维混凝土的69%和64%,当聚丙烯纤维掺量为0.6 kg/m3时,混凝土分层度较小;聚丙烯纤维在轻骨料混凝土中存在一个最佳掺量,当聚丙烯掺量为0.6 kg/m3时,混凝土28 d抗压强度变化不大,28 d抗折强度有一定提高.抗裂试验表明:对轻集料进行预湿处理和掺入纤维可以阻止和延缓混凝土早期塑性收缩产生的裂缝,提高混凝土的早期抗裂性能.The influence of polypropylene fiber on workability and strength of bridge deck pavement lightweight aggregate concrete is investigated,and the change of cracking time,cracking areas and cracking numbers are studied when lightweight aggregate is pre-wetted and polypropylene fiber and steel fiber are added in it.The results indicate that the fluidity of lightweight aggregate concrete decreases with the adding of polypropylene fiber,the initial slump and slump flow are just 69% and 64% of that without polypropylene fiber when the mixing amount of polypropylene fiber is 1.2 kg/m3.The segregation degree of concrete was small when the mixing amount of polypropylene fiber is 0.6 kg/m3.And there is an optimum mixed amount of polypropylene fiber,the compressive strength for 28 d changes little but the flexural strength for 28 d increases to some extent at 0.6 kg/m3 of polypropylene fiber.In addition,cracking resistance test indicates that it can stop and delay the crack caused by early-age plastic shrinkage by pre-wetting lightweight aggregate and adding fiber,and enhance early cracking resistance.

关 键 词：聚丙烯纤维 轻骨料混凝土 桥面铺装 抗裂性 

分 类 号：TU528[建筑科学—建筑技术科学]