混杂合成纤维道路混凝土韧性特征与机理分析  

Toughness Characteristic and Mechanism Analysis of Hybrid Synthetic Fiber Reinforced Pavement Concrete

作　　者：王帅[1] 武书华[1] 何锐[1] 盛燕萍[1] 

机构地区：[1]长安大学材料科学与工程学院,西安710061

出　　处：《硅酸盐通报》2016年第1期106-111,共6页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金资助(51508030);教育部高等学校博士点基金项目(20130205110013);中国博士后科学基金项目(2014M552397);长安大学中央高校基本科研业务费专项资金资助(2014G1311082;310831162001);浙江省交通运输厅科研计划项目(2014H38)

摘　　要：根据水泥混凝土路面的实际受力条件,采用弯曲韧性和冲击韧性两个指标对所制备的聚乙烯纤维/聚丙烯粗合成纤维混杂增强混凝土的韧性特征进行全面评价,并结合SEM微结构分析结果对其增韧机理进行了探讨。结果表明,所制备的4组混杂纤维混凝土的弯曲韧性指标均超过理想弹塑性材料的标准,并且在初裂产生后仍具有较高的强度保持能力,试件的裂缝曲折且细微,有效扩散了裂缝尖端的应力集中;混杂纤维混凝土试块的抗冲击韧性大幅提升,吸收的冲击能约是普通混凝土试块的15倍;采用聚乙烯/聚丙烯粗合成纤维可以在几何形状尺寸与力学性能上形成具有一定级配结构的纤维增强材,产生正混杂效应。According to the actual stress conditions of cement concrete pavement, flexural toughness and impact toughness were adopted to evaluate the toughness characteristic of pavement concrete reinforced with high elastic modulus polyethylene fiber and low elastic modulus polypropylene synthetic fiber. The toughening mechanism was discussed through combined with SEM mierostructure analysis. The results show that, the flexural toughness index of all the four groups prepared hybrid fiber concrete are better than standard elastic-perfectly plastic material. After the generation of first crack, the specimen still possesses high strength retention, and the crack pattern is tortuous, so that the crack tip stress concentration diffused effectively. The impact toughness of hybrid fiber reinforced concrete increases greatly. It absorbs the impact energy is about 15 times that of ordinary concrete test blocks. The reinforcing material of polyethylene fiber and polypropylene synthetic has a gradation in the size structure and mechanical properties of geometric shapes, producing positive hybrid effect.

关 键 词：纤维混凝土 弯曲韧性 冲击韧性 微结构 增韧机理 

分 类 号：TU528[建筑科学—建筑技术科学]