荷载与环境侵蚀耦合作用下钢-连续纤维复合筋（SFCB）增强混凝土构件受力性能研究

Fiber reinforced plastic tendons has the advantages of corrosion resistance, it can be used to solve durability of reinforced concrete structures in erosion environment, such as the corrosion of steel bars, the weakening of the cross-section area of steel bars and the decreasing of bearing capacity. But FRP is a linear elastic material and its elastic modulus is low, so the failure mode of FRP reinforced concrete member is brittle and its deflection and crack width is large which limited its application..Steel-fiber reinforced plastic composite bar (SFCB) as a new reinforcing composite bar which is composite of core steel bars and outsourcing longitudinal fiber. SFCB has the advantage of high strength, high elastic modulus, good ductility, stable post-yield stiffness and anti-erosion properties..SFCB reinforced concrete members which form by using SFCB replace normal steel bars or FRP bars will be studied in this project. Combined analysis method of experimental, mathematic and mechanical will be adopted. Flexural capacity, stiffness, crack, ductility, energy dissipation capacity, the whole loading process and optimal analysis of SFCB concrete members will be studied, then analysis theory and design methods of SFCB reinforced concrete members will put forward. Research reuslts will provide reference for popularization and application of SFCB concrete members so as to making full use of material properties and improving the durability of concrete structures.

FRP筋具有良好的抗腐蚀性能，可用于解决钢筋混凝土结构在侵蚀环境下钢筋锈蚀、截面面积削弱、承载力下降的问题。但FRP为线弹性材料，且弹性模量较低，导致FRP筋混凝土构件破坏为脆性，且挠度和裂缝宽度较大，限制了其推广应用。.钢-连续纤维复合筋(Steel Fiber Composite Bar，简称SFCB)是一种以钢筋为内芯外包纵向纤维的新型增强复合材料，它具有强度高、延性好、弹性模量较高、稳定的二次刚度及优异的耐腐蚀性能等特点。.本项目以SFCB代替普通钢筋/FRP筋形成SFCB混凝土构件为研究对象，采用试验分析、数学力学分析相结合的方法，重点针对正常环境、荷载与环境侵蚀耦合作用后构件的承载力、刚度、裂缝、延性和破坏形态等进行受力全过程研究和优化分析，提出SFCB筋混凝土构件的分析理论与设计方法，为SFCB筋混凝土构件的推广应用提供参考，以充分利用材料性能，提高混凝土结构的耐久性。

钢-FRP复合筋(Steel-FRP Composite Bar，简称SFCB)是一种以钢筋为内芯外包纵向纤维的新型增强复合材料，它具有强度高、延性好、弹性模量较高、稳定的二次刚度及优异的耐腐蚀性能等特点。项目以SFCB代替普通钢筋/FRP筋形成SFCB混凝土结构构件为研究对象，该种配筋混凝土结构不仅具有良好的耐久性能，而且可解决因FRP为线弹性材料、弹性模量较低导致FRP筋混凝土构件破坏为脆性、挠度和裂缝宽度较大的问题。.项目采用试验分析、数学力学分析相结合的方法，针对正常环境、侵蚀环境作用后筋材的力学性能及其与混凝土的粘结性能进行了试验研究与理论分析，建立了简化的SFCB本构模型和粘结-滑移本构模型。研究了配筋率、筋材类型、纤维类型、侵蚀环境及侵蚀时间对受弯构件和受压构件承载能力、刚度、裂缝、延性和破坏形态的影响。基于简化的本构模型、平截面假定和力的平衡，对构件受力全过程进行了分析研究。推导了构件承载能力、刚度和裂缝宽度的计算公式并给出了构件破坏形态判别公式，建立了SFCB筋混凝土构件的分析理论与设计方法。研究成果为SFCB筋混凝土构件的推广应用提供参考，可充分利用材料性能，提高混凝土结构的耐久性。