摘要
通过对24根钢-聚丙烯混杂纤维混凝土柱试件的拟静力试验,考察了其抗震性能,分析纤维种类、轴压比、剪跨比、纵向配筋率和体积配箍率等因素对试件抗震性能的影响。结果表明:柱的剪跨比、纤维种类和轴压比是试件破坏形态的主要影响因素,而柱的配箍率和配筋率的影响较小;当轴压比nt≥0.308时,混杂纤维的掺入可使试件的抗震承载力提高15%~20%;配箍率对柱的受弯承载力的影响可通过在约束条件下混凝土强度的提高予以体现。在此基础上,针对柱的弯曲、弯剪破坏形态,考虑柱端约束和箍筋约束的作用,建立了柱的受弯承载力计算公式;针对其剪切破坏形态,提出混凝土双向受力简化分析模型,建立了柱的受剪承载力计算公式,其计算值与试验值均吻合良好。
To study the seismic performance of steel-polypropylene hybrid fiber reinforced concrete columns,the effects of fiber types,axial compression ratio,shear span ratio,longitudinal reinforcement ratio and transverse reinforcement ratio were analyzed through quasi-static tests on 24 columns,and the methods for flexural and shear capacity calculation were presented. The results show that,in comparison with longitudinal reinforcement ratio and transverse reinforcement ratio,shear span ratio,fiber types and axial compression ratio have greater effects on the failure modes. The seismic bearing capacity of hybrid fiber reinforced columns can be improved by 15%-20% when axial compression ratio is beyond 0. 308. The effect of transverse reinforcement ratio on flexural capacity can be reflected on the improvement of the concrete strength under confined condition. On the basis of the experimental observations,the seismic bearing capacity calculations were proposed,for bending or bending-shear failure columns by considering the effects of end-column restraint and stirrups restraint,and for shear failure columns by introducing a simplified bidirectional loading model. The theoretical results agree well with the experiment results.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2014年第8期95-103,共9页
Journal of Building Structures
基金
国家自然科学基金项目(51278388)
