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Most of the existing mechanical models for shear strength and strain calculation of beam–column joints do not explicitly account for bond conditions of the longitudinal reinforcement of the connected members that are anchored inside the joint region. When considered, bond is accounted for through empirical parameters. In this paper, an analytical method for the definition of the strain distribution along the anchorage of the column longitudinal reinforcement inside a bridge monolithic connection is proposed. The anchorage capacity of the main column reinforcement is considered to be affected by two independent mechanisms. The capacity of the first mechanism depends on the average bond stress along the elastic part of the anchorage that is calculated by a mathematical solution without taking into account the beneficial effect of the transverse reinforcement. The capacity of the second mechanism depends on the coefficient of friction arising between main column bars and transverse reinforcement that encloses and restrains the anchorage. The coefficient of friction is empirically set in relation to the position of the transverse bar; either along the elastic part of the anchorage or in the part where yielding penetrates inside the joint. A parametric evaluation of the main design parameters affecting the anchorage capacity is conducted next. The proposed model is finally used in calculating the joint shear response of selected bridge connection specimens for which reported data of strain distribution along anchorages exist. The calculated values correlate successfully with the associated experimental data. [ABSTRACT FROM AUTHOR]

Depending on the relevant material properties, failure of grouted anchor anchorage to concrete can result from pullout of concrete cones, debonding at either anchor-grout or grout-concrete interface, fracture of anchor, and combination of some of these failure modes. The intention of the present study is to present an analytical method for analyzing the concrete cone failure during the process of interfacial debonding by using deformation compatibility conditions at the anchor-grout and grout-concrete interfaces. The tensile stress in the anchor and interfacial stresses at the two interfaces are formulated at different loading stages. It is assumed that interfacial debonding modeled as an interfacial shear crack only appears at the anchor-grout interface and is initiated from the loaded end. The concrete cone and interfacial debonding failures are analyzed according to the sizes and material properties of the anchorage. Three different failure modes are considered, including concrete cone failure at the unloaded end without interfacial debonding, interfacial debonding plus concrete cone failure at the same height as the interfacial shear crack tip, and interfacial debonding plus concrete cone failure at the unloaded end. In each case, the load for the initiation of the concrete cone failure, and the cone angle are determined analytically. Subsequently, material and structural parameters are adopted to study their influences on the failure modes and calculated results. It is found that if the embedment length is relatively long, the concrete cone failure occurs within a local scope. If the concrete diameter is large enough, the failure mode is the interfacial debonding without concrete cone failure. The conclusions provide useful references for engineering practice such as designing grouted anchor anchorage to concrete in light of different needs and failure modes. [ABSTRACT FROM AUTHOR]

The authors discuss research on the cyclic response of reinforced concrete walls with different anchorage details. They reference the study "Cyclic Response of Reinforced Concrete Walls With Different Anchorage Details: Experimental Investigation" by Sriram Aaleti and colleagues published in the journal in 2014. Topics discussed include the loading history for applying lateral load to wall specimen of a test, horizontal sliding shear cracks and the mechanism of instability of wall specimens.