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This paper presents a novel framework for assessing the impact of construction defects on bridge deck corrosion-induced deterioration. The model developed quantifies the impact of insufficient concrete cover, damage to the rebar epoxy coating, improper curing technique, and excessive water–cement ratio on the lifespan of concrete bridge decks. Regional variations, including freeze–thaw cycles, carbonation, and deicing salt usage, are also considered in the model. Two applications for estimating deterioration and decrease of condition rating are presented. Simulation results using the model developed reveal a substantial loss of life when these defects occur. This work highlights the importance of proper construction practices in ensuring long-term infrastructure integrity. Moreover, it provides a valuable tool for assessing the impact of these common construction defects on bridge deck deterioration. This tool enables bridge managers to make better-informed decisions regarding repair operations and ask contractors for fairer compensations when defective practices are observed during construction. [ABSTRACT FROM AUTHOR]

The document titled "Reviewers" is a compilation of names and affiliations of individuals who reviewed manuscripts for the Journal of Bridge Engineering from July 1, 2022, to June 30, 2023. It acknowledges and expresses gratitude for their contributions and expertise in the field of bridge engineering. The list includes reviewers from various institutions and universities worldwide, highlighting a global perspective on the subject matter. This document serves as recognition for the reviewers' valuable input and represents a diverse range of backgrounds and institutions. [Extracted from the article]

Load distribution factor for truck loads is a key parameter in evaluating the load-carrying capacity of existing bridges. This study aimed to investigate load rating procedures for reinforced concrete bridges using the tools of numerical analysis. In this study, three-dimensional finite-element modeling was used to estimate shear and bending moment demands and capacities for a sample of 10 (five flat slab and five T-beam) reinforced concrete bridges. The results were compared with those obtained using current rating procedures in accordance with AASHTO specifications. This comparison showed that the current two-dimensional analysis with the distribution factor approach resulted in lower estimates of the bridge rating, mainly due to the simplified representation of structural members and lack of consideration of the contribution of nonstructural elements. To further explore the impact of this observation, a focused parametric study was conducted to investigate the effect of geometrical features such as edge elements on moment and shear estimates. The findings confirmed the sensitivity of calculated demand considering superstructure edge elements primarily, railings, curbs, and sidewalks found in these bridges. [ABSTRACT FROM AUTHOR]

Most of the public school buildings in Turkey and Peru are built according to a small number of template plans. Over the years, these template plans are kept the same while the structural designs are varied with the seismic design codes in force. During recent strong earthquakes in Turkey and Peru, the design concepts and construction styles for these template school buildings have been put to test. In this paper, observed earthquake performances of template reinforced concrete school buildings with moment-frames or moment-frames and shear walls are compared. The comparison reveals choices in design that were successful as well as those that were not. The disastrous results of “captive columns” are demonstrated in illustrations from what has been observed in recent earthquakes in these seismically active countries. It is shown that since 1997 the Peruvian practice has been producing school buildings that perform well during strong earthquakes. [ABSTRACT FROM AUTHOR]

An experimental research program was undertaken to define the effects of long-term deformations on the seismic performance of reinforced concrete columns. Thirteen beam–column specimens were subjected to simulated seismic drift histories after the columns sustained axial load for a predefined duration. The experiments are supplemented by computer analyses that simulate: (1) the changes in column internal stresses due to long-term deformation of concrete during the sustained load period, and (2) stress and strain demands from nonlinear flexural response to short-term lateral loading. Columns which sustained load for longer durations were observed to develop inclined cracks at earlier stages of the lateral load tests due to a combination of (1) reduced concrete compression stresses from axial stress redistribution, and (2) transverse tension stresses in the column core due to restrained shrinkage of the concrete. This damage produced decreases in (1) lateral stiffness prior to column hinging, (2) flexural strengths at first yield and ultimate, and (3) toughness (as indicated by energy dissipated through hysteresis). However, the observed reductions in flexural strength did not exceed 15%, and, in most cases, column drift capacity exhibited improvement with sustained load duration. [ABSTRACT FROM AUTHOR]

This paper presents the first series of validation tests for a patented shear reinforcement system for reinforced concrete flat slabs. The system, called “Shearband,” consists of elongated thin steel strips punched with holes, which undulate into the slab from the top surface. The main advantages of the new reinforcement system are structural effectiveness, flexibility, simplicity, and speed of construction. Four reinforced concrete slabs were tested in a specially designed test rig. The slabs reinforced in shear exhibited ductile behavior after achieving their full flexural potential, thus proving the effectiveness of the new reinforcement. This paper reviews briefly existing types of shear reinforcement and identifies the need for more efficient and economic solutions. Details of the experimental setup and results are given, including strain and deflection measurements as well as photographs of sections through the slabs. Finally, comparisons are made with the ACI 318 and BS8110 code predictions, which confirm that the system enabled the slabs to avoid punching shear failure and achieve their flexural potential. In addition, both codes are shown to lead to conservative estimates of flexural and punching shear capacities of reinforced concrete slabs. [ABSTRACT FROM AUTHOR]

This paper describes a theory, according to which the shear failure of reinforced concrete deep beams under two-point or a single-point loading, with a shear span to effective depth ratio (a/d) between 1.0 and 2.5, is due to a crushing of concrete in a compression zone with a restricted depth above the tip of the critical diagonal crack. Simple expressions are derived for the restricted depth of the compression zone, as well as for the ultimate shear force of deep beams with and without web reinforcement. The derived formulas from this analysis are verified by comparisons to extensive sets of experimental data from literature, which have been obtained on deep beams with various strengths of concrete, main steel ratios, shear reinforcement ratios, and shear span to depth (a/d) ratios between 1.0 and 2.5. [ABSTRACT FROM AUTHOR]

Existing microplane models for concrete use three-dimensional spherical microplanes in the analysis of two-dimensional planar members as well as three-dimensional members. Also, they do not accurately describe the postcracking behavior of reinforced concrete in tension-compression. In this study, a new microplane model is developed to overcome the disadvantages of the existing models. Instead of the existing spherical microplanes, the proposed microplane model uses disk microplanes involving a less number of microplanes and two-dimensional stresses and strains. As the result, the proposed model is more effective in numerical calculation. Also, the concept of the strain boundary is introduced to describe accurately the compressive behavior of reinforced concrete with tensile cracks in tension-compression. The validity of the proposed model was verified by comparison with existing experiments. In this paper, the microplane model and the numerical techniques involved in the finite-element analysis are described in detail. [ABSTRACT FROM AUTHOR]

Masonry infill panels in framed structures have been long known to affect strength, stiffness, and ductility of the composite structure. In seismic areas, ignoring the composite action is not always on the safe side, since the interaction between the panel and the frame under lateral loads dramatically changes the stiffness and the dynamic characteristics of the composite structure, and hence, its response to seismic loads. This study presents a simple method of estimating the stiffness and the lateral load capacity of concrete masonry-infilled steel frames (CMISFs) failing in corner crushing mode, as well as the internal forces in the steel frame members. In this method, each masonry panel is replaced by three struts with force-deformation characteristics based on the orthotropic behavior of the masonry infill. A simplified steel frame model is also presented based on the documented modes of failure of the CMISF. The method can be easily computerized and included in nonlinear analysis and design of three-dimensional CMISF structures. [ABSTRACT FROM AUTHOR]

Floor slabs of deep basement structures are subjected to large compressive forces due to soil and hydraulic lateral pressures. In this study, nonlinear finite-element analyses were carried out to improve the existing moment magnifier method so that it is applicable to the long-term behavior of the flat plates. For this purpose, a computer program that can address creep and shrinkage as well as geometrical and material nonlinearity was developed. Parametric studies were performed to investigate the characteristics of the long-term behavior and the load-carrying capacities of flat plates. In the proposed moment magnifier method, the creep factor was introduced to accommodate the effect of creep on the load-carrying capacity. A design example was presented to demonstrate the proposed design method. [ABSTRACT FROM AUTHOR]

The behavior of concrete exposed to fire is highly influenced by stress-temperature path. Any stress-temperature path consists of two basic paths: the path of constant temperature but subjected to increasing stress (TS path), and the path of constant stress but subjected to elevated temperature (ST path). The concrete mechanical strain for the TS path can be obtained experimentally, but it is difficult to obtain the mechanical strain for the ST path due to nonuniform temperature distribution within the concrete specimen. In this paper, through analyzing the stress versus mechanical strain curves of concrete from test results for the TS path, a new concept, known as the "temperature-flow mapping" method, is proposed. Based on this concept, temperature versus mechanical strain relationships of concrete for the ST path can be obtained from those curves for the TS path. Mathematical expressions for the concept are also given in the paper. It is found that the predictions based on this concept are in good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Reinforced concrete columns can be strengthened by a fiber-reinforced polymer (FRP) jacket which provides lateral confinement to the column. This technique is very effective for circular columns, but its effectiveness is much reduced for rectangular columns. One possibility to increase the effectiveness of FRP confinement for a rectangular column is to modify the column section into an elliptical section. For such section modification to be widely adopted in practice, it is necessary to develop a good understanding of the behavior of FRP-confined concrete in elliptical columns. This paper therefore presents the results of an experimental study on FRP-confined concrete in elliptical columns. Test results are first presented, which indicate that although the confining FRP becomes increasingly less effective as the section becomes more elliptical, substantial strength gains from FRP confinement can still be achieved even for strongly elliptical sections. The ultimate axial strain of the confined concrete is also shown to increase as the FRP confinement becomes stronger. Based on the test results, a simple compressive strength model for FRP-confined concrete in elliptical columns is proposed, in which the effect of the section shape is taken into account by a shape factor. [ABSTRACT FROM AUTHOR]

There is considerable uncertainty regarding both the timing and contributions of various individuals to the development of reinforced concrete flat slabs in the United States. The work of George M. Hill and the patent of Orlando W. Norcross are discussed first to provide context. The significant achievements of Claude A. P. Turner from 1905 to the end of 1909 are then described. Turner's conceptual design of flat slabs is discussed. Turner conceived a cage of reinforcement, which he called the "mushroom head," as shear reinforcement. Turner's simple design for moment led to very small areas of steel flexural reinforcement, which drew criticism from structural engineers. Some early flat-slab buildings and bridges and the load tests that Turner performed are discussed. A tangible symbol of Turner's contributions is his extant 1906 Hoffman (a.k.a. Marshall) building, which was designated an ASCE National Historic Civil Engineering Landmark in 2002. The dispiriting history of flat-slab development after the end of 1909 is briefly discussed. There is considerable uncertainty regarding both the timing and contributions of various individuals to the development of reinforced concrete flat slabs in the United States. The work of George M. Hill and the patent of Orlando W. Norcross are discussed first to provide context. The significant achievements of Claude A. P. Turner from 1905 to the end of 1909 are then described. Turner's conceptual design of flat slabs is discussed. Turner conceived a cage of reinforcement, which he called the "mushroom head," as shear reinforcement. Turner's simple design for moment led to very small areas of steel flexural reinforcement, which drew criticism from structural engineers. Some early flat-slab buildings and bridges and the load tests that Turner performed are discussed. A tangible symbol of Turner's contributions is his extant 1906 Hoffman (a.k.a. Marshall) building, which was designated an ASCE National Historic Civil Engineering... [ABSTRACT FROM AUTHOR]

The main aim of this study is to propose a simple and reliable method to predict the buckling length of longitudinal reinforcing bars and also to predict the spalling of cover concrete in reinforced concrete members. Stability analysis is conducted giving due consideration to both geometrical and mechanical properties of the longitudinal reinforcing bars and lateral ties. The tie stiffness required to hold longitudinal reinforcing bars in different buckling modes is derived from energy principles, and it is compared with actual tie stiffness to determine the stable buckling mode. The buckling length is computed as the product of the stable buckling mode and the tie spacing. The proposed buckling length determination method is experimentally verified for various cases. A design method for lateral ties to avoid buckling-induced strength degradation is also recommended. The effect of lateral deformation of longitudinal bars is quantitatively evaluated and incorporated in the simulation of cover concrete spalling. Analytical prediction considering spalling and buckling according to the proposed methods showed better agreement with the experimental result. [ABSTRACT FROM AUTHOR]

The average stress condition in a reinforced concrete (RC) element is not identical to the local stress condition at a crack because of bond slip between the concrete and the reinforcement. After a review of previous research concerning local stresses at cracks, this paper presents local equilibrium and compatibility equations for RC elements given constitutive models for bond and friction. A procedure is described for analyzing the in-plane pure shear response of orthogonally reinforced concrete panels. The procedure considers stress variations between cracks, the crack formation process, and the slip δ[sub t] accompanying the friction across a crack. Corresponding analytical results are compared with previous experimental work. It is shown that after the residual tension at the crack is lost, the slip δ[sub t] increases almost proportionally to the normal crack displacement δ[sub n]. Accompanying local shears τ[sub ct] remain because of friction even when the normal crack displacement continues to increase. [ABSTRACT FROM AUTHOR]

A simplified method for the analysis and design of membrane elements subjected to in-plane shearing and normal stresses is presented. The method proposed is capable of calculating the ultimate strength and the mode of failure of membrane elements. The strength curves in the method are also cast in a tabular format to further simplify the method. The results of the proposed method compare well with experimental results of 14 membrane elements reported in the literature and with the results of the modified compression field theory. Comparisons with the general method and the American Concrete Institute code are also presented. Use of the method is illustrated by two examples, one for design and the other for capacity calculation. [ABSTRACT FROM AUTHOR]

The purpose of this experimental research program was to verify that the transfer and development length of 15-mm (0.6-in.) diameter prestressing strand were less than calculated by the current American Association of State Highway and Transportation Officials Specifications when used in high performance concrete bridge girders. The scope was limited to testing four AASHTO Type II girders, two made from 70 MPa and two from 100 MPa design strength concretes. Transfer length was determined by measuring strand end slip and concrete surface strain. Development length was determined by performing eight flexure tests with varying embedment lengths. Transfer length averaged 447 mm (17.6 in.) and 371 mm (14.6 in.) for the 70 and 100 MPa concretes, respectively. The development length was found to be 2032 mm (80 in.). These values were less than those given by the current AASHTO and ACI code provisions; therefore it is recommended that current code provisions be used for pretensioned concrete girders with strengths up to 100 MPa. [ABSTRACT FROM AUTHOR]

Multicellular concrete box docks are an extensively used structural alternative for building vertical harbor quays or breakwaters. The prefabrication techniques employed for building them guarantee quality, speed, and cost control, conditions difficult to achieve with more traditional technologies. However, a major problem arises from the fact that both their constructive process and their setting in operation may generate levels of strain above those corresponding to normal service. Consequently, intermediate load states need to be considered in the design phase of the box dock. Another aspect to be taken into account is the three-dimensional behavior of the box dock that cannot be completely described using the traditional simplified approaches almost exclusively employed in actual design. It is shown how a global safety factor may be deduced through use of material nonlinear analysis and how this may help in the design process of a box dock. This study is focused on the possibility of eliminating the vertical reinforcement steel bars of box docks. DOI: 10.1061/(ASCE)0733-9445(2002)128:5(603) [ABSTRACT FROM AUTHOR]

Presents a series of comments on shear design of structural concrete.

Presents the results of analytical investigation of the strength and structural behavior of concrete members prestressed with external tendons. Overview on the analytical model; Model validation; Conclusions.

Determines the strength and ductility of an existing concrete bridge and the improvements that can actually be achieved using a carbon fiber reinforced polymer advanced composite retrofit. Objectives of retrofit and in situ tests; Advanced composite retrofit design; Conclusions.

Provides information on a study on the beam-column behavior of a high-performance structural member made of concrete-filled fiber-reinforced plastic tubes. Details on the experimental program; Discussion of results; Conclusions.

Provides information on a study which examined the static and fatigue performance of reinforced concrete beams strengthened with externally bonded carbon-fiber-reinforced plastic sheets. Description of the test program; Details on the test setup and procedure; Discussion of the test results; Conclusions.

Provides information on a study which examined a two-story, two-bay reinforced masonry infilled concrete frame by pseudodynamic testing of a half-scale specimen. Specimen instrumentation and properties; Information on the pseudodynamic test method; Conclusions.