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Welded-wire reinforcement (WWR) is widely used as the main reinforcement in bridge decks and vertical shear reinforcement in concrete bridge girders. Previous studies on concrete members re...

Secondary circulation is a mechanism that increases vertical exchange between the horizontal layers in open channels. Vertical shear in curved flows induces secondary circulation in the pla...

Six full-scale reinforced-concrete (RC) interior slab-column connections of glass fiber–reinforced polymer (GFRP) were constructed and tested to failure. The specimen consisted of a square slab with a 2,800-mm side length and a 200-mm thickness in addition to a 300-mm-square column stub extended for 1,000 mm above and below the slab. The test specimens were subjected to vertical shear forces and unbalanced moments. The test variables included the moment-to-shear ratio, GFRP double-headed shear studs ratio, and the type of GFRP bar surface texture (ribbed or sand-coated). The test results revealed that increasing the moment-to-shear ratio reduced the vertical shear capacity and increased the deflections and the strains at failure. Moreover, the presence of the GFRP shear studs enhanced the slab capacity but was not able to change the punching shear mode of failure. Furthermore, the used two types of GFRP bars showed comparable behavior. The results were compared with the predictions of the availabl...

The Westergaard expressions for stresses and displacements in a half-space of Westergaard material are shown to be invalid because the vertical shear stress does not vanish at the plane boundary of the half-space. The same inadequacy is discovered in the solution for a horizontally rigid cross-anisotropic half-space deduced from Michell’s expressions. A surprising conclusion is drawn, namely, that there is currently no exact elastic solution for the stresses and displacements in a horizontally rigid cross-anisotropic half-space. The Westergaard theory should cease to be regarded as an exact elastic solution for a problem of the theory of elasticity.

The monolithic structural action of various types of walls of flanged cross section and walls with engaged stiffeners or returns (nonrectangular sections) is critically dependent on the shear capacity of the interface between the components making up the section. An assessment of the shear capacity of the interface may also be required as part of the elastic or inelastic analysis of structural elements. Observation of past earthquake events has confirmed that effectively connected flanges also directly influence the seismic performance of nonrectangular sections by providing a more robust and seismically resistant structural element. To analyze the significance of the parameters that influence the vertical shear resistance of interfaces of flanged sections of masonry obtained using different types of bonding and bonding patterns (header units, shear connectors, and wire ties), a series of specimens with "H-shaped" cross sections was tested. The vertical shear capacity of the interface at the flange-web intersection was assessed in each case and compared to predicted code capacities. Considerable strength reserves and shear ductility were observed in almost all cases. Following the experimental study, a numerical investigation was carried out using a simplified micromodeling finite element approach. It showed that both the size of the specimen as well as the boundary and applied loading conditions on the flanges can significantly influence the observed vertical shear resistance of the interfaces of specimens with the same bonding pattern. Using the results of the numerical investigation, the critical parameters for a test to determine the vertical shear capacity of brick masonry nonrectangular cross sections are assessed and the governing parameters for a suitable shear test suggested.

The technique of adhesively bonding steel or fiber-reinforced plastic plates to the surfaces of reinforced concrete (RC) structural elements is being adopted worldwide to strengthen or repair reinforced concrete buildings and bridges. However, the prevention of premature debonding or peeling of externally bonded plates is a most critical aspect of design. One of the major modes of debonding in plated RC beams is shear peeling induced by the formation of critical diagonal cracks caused by the applied vertical shear forces. In this paper, mathematical models are developed for quantifying the shear peeling resistance of RC beams bonded with plates of different configurations. These models are based on the simplified theory of plasticity concepts for shear in reinforced concrete beams and also on procedures to compute the bond strength between an adhesively bonded plate and a concrete element. The models are validated against 32 test results from reinforced concrete beams adhesively bonded with either steel p...

Massive concrete walls constructed on rock foundations, as well as other nonmoving retaining walls, are customarily designed for at-rest earth pressures. Vertical shear loads applied by the backfill are usually not considered in design of nonmoving walls, even though many field and laboratory measurements have shown that such loads exist. Vertical shear loads can be very beneficial for stability of retaining walls, because they provide restoring moments to counteract overturning moments from lateral earth loads. In this paper, model test results and case history data are reviewed, the results of finite-element calculations are presented, and a simple design procedure is developed. It is shown that significant economies can result from consideration of vertical shear forces in design of nonmoving retaining walls.

Retaining walls that do not move are customarily designed based on the assumption of at-rest conditions, with no consideration of vertical shear loads applied by the backfill. However, field and laboratory measurements have shown that vertical shear loads do act on nonmoving walls. A simple theory for calculating the magnitude of vertical shear loads on nonmoving walls is presented in this paper, and typical results from the theory are discussed. A companion paper presents the results of finite-element calculations, case history data, and recommendations for retaining wall design.

This article comments on earlier research on composite beams with web openings (Park, Kim, Yang, 2003). The beams studied have ribbed slabs with the ribs oriented transversely. The effects of slab width and moment-shear ratio on failure mode and strength were studied and the authors found that the failure mode of concrete slabs depends on the slab width. Strength predictions of a proposed model were also compared with test results and predictions of other strength models. In this commentary, Cho focuses on the truss analogy and discusses several aspects adopted by the authors in the formulation of the shear strength equations at web holes of composite beams against the common knowledge of structural mechanics. Cho makes four points: the authors misunderstood the truss analogy proposed by Cho and Redwood (1992); in the authors' study, the full slab width was assumed to be capable of carrying the vertical shear forces, even though this is not an ordinary understanding of the slab shear behavior; comparisons and evaluations should also include the predictions by the Redwood group methods other than the truss analogy; and the truss analogy predicts better narrow slab beams, rather than wide slab beams.

Results of field and laboratory research on cellular sheetpile structures are summarized. Design for both internal stability and overall stability is considered. It is proposed that for cellular bulkheads embedded in sands, neither sliding nor overturning can occur before a cell fails by tilting in the vertical shear mode. Guides for interlock force analysis and selection of lateral earth pressure coefficients for a newly proposed vertical shear model are given.

Variation of slope deflection method whereby all deformations of combined system of rigid frames and vertical shear trusses or walls are approximated by power series; their arbitrary constants will be determined by partial differentiation of virtual work equations of total system.

THE AUTHOR INVESTIGATED 3 APPROACHES TO THE VERTICAL SHEAR PROBLEM AFTER FINDING TERZAGHI'S ORIGINAL APPROACH AND KRYNINES MODIFICATION OF IT NOT REALISTIC. HE CONCLUDED THAT THE MOST REASONABLE APPROACH IS ESSENTIALLY TERZAGHIS ORIGINAL APPROACH BUT WITH THE NORMAL STRESSES ON THE HORIZONTAL AND VERTICAL PLANES EQUAL TO EACH OTHER. THE DISCUSSER AGREES WITH THESE CONCLUSIONS, BUT GIVES EVIDENCE THAT DESTROYS THE MAIN JUSTIFICATION FOR THE VERTICAL SHEAR FAILURE APPROACH. THEREFORE, THE DISCUSSER AGREES WITH THE AUTHORS STATEMENT THAT ANOTHER METHOD, PREFERABLY BRINCH HANSEN METHOD, SHOULD REPLACE THE VERTICAL SHEAR METHOD. HANSEN'S METHOD CAN BE EASILY PROGRAMMED FOR A COMPUTER.