Analytical And Experimental Study On Adhesive Anchors

Anchors have been successively used for in-situ soil reinforcement, slope stabilization, deep excavation support and reinforcements of concrete structures. Understanding the mechanism of the anchorage system is essential to achieve an efficient design. The structure of anchorage system is very complicated and it consists of five elements that are three mediums and two interfaces. The mechanical properties of these five elements determine the ultimate load-carrying capacity of the anchorage system directly. In this paper, focus is placed on the fundamental study of bonding behavior of two interfaces, the strength and deformation prosperities of grouting body under loading condition as well as the calculation and prediction of ultimate load-carrying capacity of anchorage system by experimental research, theoretical analysis and numerical simulation. The major contributions are summarized as follows:1 The test on 15 short-anchorage-length pullout specimens under monotonic loading is carried out. The whole processes of bond failure with various rebars are studied. The influences of surface configurations and diameters of rebars, as well as the strength of grout on the bonding strength of rebar-mortar interface are analyzed. Based on the experimental results, three interfacial characteristic parameters including interfacial shearing strength, interfacial shearing stiffness and interfacial frictional strength are calculated.2 Triaxial compressive tests on strength and deformation of grout are carried out. The failure modes of grout under triaxial compression are analyzed. The effect of stress ratios and intermediate principal stress on the strength of grout is studied. The failure criterion in octahedral coordinates is proposed based on the test results.3 A newly developed pushout method is adapted to investigate the bonding strength of the grout-concrete interface. The whole processes of bond failure of grout-concrete interface are analyzed based on the P- δ curves. The influences of strength of grout and diameter of drilled hole on the bonding strength of grout-concrete interface are studied.4 An interfacial mechanics model is proposed and several interfacial characteristic parameters as tokens of bonding strength of interface during the grout pushed out are calculated according to this model. The calculated values of characteristic parameters agreed well with the experimental results.5 The FEM is adapted to analyze the stress distribution in the concrete during the grout is pushed out and study the reason that lead to the failure of concrete.6 An analytical method is presented for push-out of a mortar cylinder from a concrete block. Using the proposed method, the expressions of compressive stress in the mortar and interfacial shear stress at the mortar-concrete interface are gained analytically during the elastic stage...