摘要
为研究混凝土材料的抗裂性能,针对新型桥梁建筑材料———钢纤维增强聚合物改性高强混凝土(SFRPMHC),基于边界效应模型,提出用不同边界条件试件确定无尺寸效应断裂韧性的测试方法,并通过6组不同钢纤维及聚合物含量、3种不同缝高比的预制开口试件的验证,研究了材料组份对断裂韧性的影响规律.结果表明直接由试验确定的名义断裂韧性仍有尺寸效应,边界效应模型可较好描述这一规律;随钢纤维含量的增加,混凝土抗压、抗拉强度及失稳断裂韧性均线性增大,而起裂断裂韧性提高不明显;聚合物含量越大,材料抗压强度和断裂韧性也略有增大.
In order to study the crack resistance of a new material used in bridge construction-- Steel Fiber-Reinforced and Polymer-Modified High-strength Concrete （SFRPMHC）, based on the boundary effect model, a new test method was proposed to determine the size-independent facture toughness, and 6 groups of SFRPMHC with different steel fiber and polymer content, in 3 different notch-to-depth ratios, were carried out to validate the method and the influence of additive content on the fracture toughness were investigated either. Results indicated that the nominal fracture toughness indexes measured in test directly also had size effect and the boundary model could be used to describe these laws. The compressive/spitting tensile strength and the unstable fracture content increasing, while toughness showed a tendency of linear increase when steel-fiber initial fracture toughness improving not obviously; following by polymer emulsion increased, compressive strength and fracture toughness of concrete increase slightly.
出处
《应用基础与工程科学学报》
EI
CSCD
2011年第6期963-970,共8页
Journal of Basic Science and Engineering
基金
国家自然科学基金项目(10672060
11132004)
广东省自然科学基金项目(9251064101000016)
