Experimental Investigation On The Bond Properties Between T Section Steel And Concrete In SRC Structures

In this thesis, referring to the domestic and overseas bond-slip test between reinforced bar and concrete in RC structures as well as steel shape and concrete in SRC structures, the push-out tests of 8 specimens were conducted to study on bond-anchorage properties between T section steel and concrete in SRC structures, which were impacted by three main factors including concrete stress, volume ratios of stirrups and thicknesses of concrete cover of section steel. The research below is about the bond-anchorage problem of T steel reinforced concrete:(1) Based on the data from the test, the factors that affect T steel reinforced concrete anchorage length are analyzed. With the help of Multiple Linear Regression, the calculation formula of T steel reinforced concrete anchorage length is fitted.(2) Based on the test, the data from external load value of each specimen's load side and the relative slip between steel and concrete are analyzed, concluding that the shaped steel deformation is exponentially distributed along the anchorage length, and mathematical expression is obtained through statistical regression of the curves corresponding. The relationship between bond stressesτ(x) and steel shape strainsεss(x) is derived from the force balance equations, and the distribution of bond stress is obtained, i.e. the distribution of bond stress is similar to exponential distribution along anchorage length.(3) According to the principles and methods of steel reinforced concrete bond strength reliability analysis and the ultimate bond strength formula created in literature [15] and combining the experimental sample data, the reliability of T steel reinforced concrete bond strength is analyzed, and the design formula of T shaped steel critical anchorage length is provided.(4) According to mathematical statistics, the design formula of obtaining the anchorage length through two ways are briefly compared and analyzed.(5) According to the ultimate bond strength of steel reinforced concrete and the formula of critical anchorage length established in the previous literature, the shaped steel reinforced concrete with three different sections of steel plate, T steel and H steel are compared under three different factors as concrete strength, concrete cover thickness and transverse stirrup.This experimental study and theoretical analysis shows that:Steel sections of features T play an important role in the bond between the shaped steel and concrete. In practical engineering applications, steel sections with large steel sections of features T can be considered or set the shear connectors, which can improve the natural bond between steel and concrete more effectively, reduce the anchorage length of steel in concrete, and generate higher economic benefits.