【摘要】：纖維增強復合材料(簡稱FRP)以其輕質(zhì)高強、耐腐蝕性能好等優(yōu)點在土木工程領域得到了廣泛的關注和應用。為了改善沿海和海島地區(qū)混凝土結(jié)構(gòu)的耐久性問題,本課題設計了外包GFRP板鋼筋混凝土構(gòu)件,即采用U型GFRP板充當模板,使用中保護內(nèi)部的鋼筋混凝土免受侵蝕；同時GFRP與混凝土緊密結(jié)合,通過組合作用提高構(gòu)件的受力性能,減少鋼筋用量,并通過內(nèi)部混凝土的填充有效增強GFRP板的整體和局部穩(wěn)定性,避免其發(fā)生側(cè)扭屈曲和局部屈曲破壞的可能。針對這種具有高耐久性的外包GFRP板鋼筋混凝土構(gòu)件,本文開展了以下幾方面的工作： 1、對外包GFRP板鋼筋混凝土梁及普通鋼筋混凝土對比梁進行抗彎性能試驗,結(jié)果表明外包GFRP板鋼筋混凝土梁的抗彎承載力較普通鋼筋混凝土對比梁的承載力有顯著提高,但延性較差。 2、對外包GFRP板鋼筋混凝土梁的彎曲破壞模式進行了劃分和判別,引入受約束混凝土本構(gòu)模型,提出了不同彎曲破壞模式下外包GFRP板鋼筋混凝土矩形截面梁和T形截面梁的受彎承載力計算公式,計算值與試驗值吻合較好。 3、對外包GFRP板鋼筋混凝土梁及普通鋼筋混凝土對比梁進行了抗剪性能試驗,試驗結(jié)果表明：外包GFRP板鋼筋混凝土梁的抗剪承載力隨著剪跨比的增大而減小。利用現(xiàn)有的抗剪承載力模型對外包GFRP板鋼筋混凝土梁的抗剪承載力進行了驗算,計算值與試驗值吻合較好。 4、對外包GFRP板鋼筋混凝土梁的彎矩-曲率關系進行了全過程分析,分析了外包GFRP板鋼筋混凝土梁的延性,推導了外包GFRP板鋼筋混凝土梁的短期抗彎剛度計算公式。 5、對外包GFRP板鋼筋混凝土梁進行了真實海洋環(huán)境下的暴露試驗,試驗結(jié)果表明,真實海洋環(huán)境下試驗梁的承載力和延性有顯著的下降。分析了暴露試驗梁結(jié)構(gòu)性能退化的機理,并提出了其受彎承載力的退化模型。
[Abstract]:Fiber reinforced composite (FRP) has been widely used in the field of civil engineering due to its advantages of light and high strength and good corrosion resistance. In order to improve the durability of concrete structures in coastal and island areas, this paper designs the reinforced concrete members of outsourced GFRP slabs, that is, U-shaped GFRP slab is used as a template to protect the internal reinforced concrete from erosion. At the same time, GFRP and concrete are closely combined to improve the mechanical behavior of the members, reduce the amount of steel, and effectively enhance the overall and local stability of the GFRP slab through the filling of internal concrete. The possibility of lateral torsional buckling and local buckling failure is avoided. In view of this kind of reinforced concrete members with high durability, the following work has been done in this paper: 1. The flexural behavior tests are carried out on the reinforced concrete beams of the GFRP slab and the normal reinforced concrete contrast beams. The results show that the flexural capacity of reinforced concrete beams with GFRP slabs is significantly higher than that of conventional reinforced concrete beams, but the ductility is poor. 2. The bending failure modes of reinforced concrete beams with GFRP slabs are divided and distinguished, and the confined concrete constitutive model is introduced. The formulas for calculating the flexural capacity of reinforced concrete rectangular section beams and T-shaped beams of GFRP slabs under different bending failure modes are presented. The calculated values are in good agreement with the experimental values. 3. The shear behavior tests of reinforced concrete beams with GFRP slabs and normal reinforced concrete beams are carried out. The results show that the shear capacity of reinforced concrete beams with wrapped GFRP slabs decreases with the increase of shear span ratio. Based on the existing shear bearing capacity model, the shear bearing capacity of reinforced concrete beams with GFRP slabs is checked and calculated, and the calculated values are in good agreement with the experimental values. 4. The relationship between bending moment and curvature of reinforced concrete beams with GFRP slabs is analyzed. The ductility of reinforced concrete beams of GFRP slabs is analyzed, and the calculation formula of short-term flexural stiffness of reinforced concrete beams with GFRP slabs is derived. 5. Exposure tests of reinforced concrete beams with GFRP slabs are carried out in real marine environment. The experimental results show that the bearing capacity and ductility of test beams in real marine environment have decreased significantly. The mechanism of structural degradation of exposed test beams is analyzed, and the degradation model of its flexural capacity is proposed.
【學位授予單位】：浙江大學
【學位級別】：博士
【學位授予年份】：2013
【分類號】：TU375.1

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本文編號：2412904