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Due to the shear strain in the plane of the slab, the parts of the slab remote from the steel beam lag behind the part of the slab located in its proximity. This shear lag effect causes a non-uniform stress distribution across the width of the slab. As a result, several standards have introduced the concept of an effective flange width to simplify the analysis of stress distribution across the width of composite beams. Both the computed ultimate moment and serviceability limit states are directly impacted by the effective width. The effect of using a large number of contact points as shear connectors on the effective width of a steel beam flange has not been investigated. A three-dimensional finite element analysis is carried out in this paper. The ABAQUS software (version 6.14) is used for this purpose, where several variables are considered, including the surface area connecting the steel beam and concrete slab, the transverse space, and the number of shear connectors. It was discovered that the number of shear connectors on the steel beam flange has a major impact on the effective width. The many connectors work together to provide a shear surface that improves the effective width by lowering the value of the shear lag.

The existing research primarily focuses on wood-concrete composite beams, with limited studies on the bending performance and effective width of wood-concrete composite slabs. A full-scale composite slab with screw connections was constructed and subjected to static load testing. The study extensively investigated the ultimate bearing capacity, load-deflection curves, interface slips, strain distributions of cross-section and effective width of the wood-concrete composite slab. It was found that the failure mechanism of the composite slab involved both bending and tensile failure of the wood beams. As the applied load intensified, a marked augmentation in the longitudinal strain of the concrete slab was observed; along the width direction, the longitudinal strain of concrete slab manifested a curved distribution. The precise determination of the effective width of the concrete slab within the composite floor could be accurately achieved via the utilization of a simplified computational approach. In order to simplify the analysis, the M-shaped section of composite slab was approximated as T-section composite beams when evaluating the bending behavior. The linear-elastic model was shown to be accurate in predicting the bending stiffness and load-carrying capacity of composite slabs.

The existing research primarily focuses on wood-concrete composite beams, with limited studies on the bending performance and effective width of wood-concrete composite slabs. A full-scale composite slab with screw connections was constructed and subjected to static load testing. The study extensively investigated the ultimate bearing capacity, load-deflection curves, interface slips, strain distributions of cross-section and effective width of the wood-concrete composite slab. It was found that the failure mechanism of the composite slab involved both bending and tensile failure of the wood beams. As the applied load intensified, a marked augmentation in the longitudinal strain of the concrete slab was observed; along the width direction, the longitudinal strain of concrete slab manifested a curved distribution. The precise determination of the effective width of the concrete slab within the composite floor could be accurately achieved via the utilization of a simplified computational approach. In order to simplify the analysis, the M-shaped section of composite slab was approximated as T-section composite beams when evaluating the bending behavior. The linear-elastic model was shown to be accurate in predicting the bending stiffness and load-carrying capacity of composite slabs.

The effective width is a relevant parameter for the design of bridge overhang slabs under concentrated loads. Experimental tests have been used to assess expressions for its calculation. However, the load capacity increases with the width until a transition area is reached. Test specimens may have lacked enough width to reach full shear capacity, affecting thus the evaluation of the results. On the other hand, within the transition area, a threshold value has been hypothesized to match the effective width. This paper aims to provide recommendations for minimal widths that guarantee the full capacity of overhang slabs and to assess the calculation of the effective width by means of the threshold value and other formulations. The effect of the edge beam is also considered. A campaign of validated non-linear FE-simulations based on experiments on range of width-span ratios was performed. The results suggest using a width-span ratio of at least 4.0 for slabs without an edge beam and 5.3 for slabs with an edge beam for the experimental practice. The efficiency of the formulation for the effective widths is diffuse and the use of threshold value leads to unsafe predictions. Instead, linear-elastic FE-analyses are recommended for the design practice.

Most international codes of practice didn't consider the flange contribution of reinforced concrete T-beams in shear strength. In inverted T-beams loaded on the web, if the flange area is considered in shear strength, the results may be overestimated because after the web cracks open, the aggregate interlock which has a more significant contribution to shear decreases, and shear stresses tend to concentrate at the compression zone, which is located in the web of inverted T-beams. To quantify flange contribution, an experimental program backed by a finite element program based on a nonlinear 3D finite element model was carried out. The experimental program investigates the shear response of beams with varying flange geometry and reinforcement. the results showed that by increasing the flange geometry, the shear strength rises but up to a certain point, the contribution of the flange reinforcement to shear must be neglected. In the current analysis, the greatest contribution of flanges was determined to be 44.5% of total shear resisted by control beam without flange. Furthermore, the numerical model was utilized to visualize and quantify characteristics that are difficult to get experimentally, such as shear stress distribution between the web and the flanges. Also, the model was used to solve a matrix of beams to obtain the maximum shear resistance to make an accurate simplified computational model which shows good agreement with the experimental and finite element results.

A new method for evaluating the effective flange width of simply supported rectangular box-girders in bending is illustrated. It aims to overcome the lack in the literature of a general method able to supply the effective flange width for a general distribution of loads along the beam axis, not restricted, i.e., to the few cases reported in standard codes. The method consists of finding an analytical expression for the effective width under sinusoidal loads of arbitrary wavelength and combining the results in the framework of a Fourier analysis. The model allows investigating the shear-lag effects on displacements and stresses. The analytical formulation proposed is validated against numerical results supplied by refined Finite Element analyses.

Effective width is known as an important parameter in the analysis and design of non-rectangular Reinforced Concrete (RC) shear walls. Current design codes, i.e., ACI, CEN, UBC, and BS, propose a constant value for the effective width calculation of flanged sections, which proved to be conservative and ineffective in some cases. Of the conventional non-rectangular RC shear walls, the L-shaped sections have rarely been investigated in the technical literature. As the L-shaped RC shear walls can extensively be employed for structural and architectural reasons, a reliable assessment of the effective width of L-shaped sections is essential. Therefore, this paper attempts to propose applicable formulations for the effective width estimation of L-shaped RC shear walls. In that regard, a number of numerical investigations involving finite element analyses have been conducted in the ABAQUS software in order to evaluate the cyclic performance of L-shaped RC shear walls. The numerical results including the axial strain and displacement distributions have been attained for 42 L-shaped RC shear walls with three different aspect ratios, at which the shear-lag effects have been taken into consideration. In addition, on the basis of the evolutionary polynomial regression (EPR) analyses, applicable formulations have been established to be utilized for the initial estimation of the effective width of the L-shaped sections. The effectiveness of the proposed expressions has been examined by assessing the R-factor of the estimations. On account of the average R-factor of 0.88, the capability of the proposed expressions has been ascertained in assessing the effective width of L-shaped sections. Moreover, in order to further highlight the unavoidable effects of level of axial loading and drift values on the variation of the effective width, different curves have been presented. Furthermore, calculation of the Mean Absolute Relative Error (MARE) index demonstrates that uniform distribution can well estimate the effective width of L-shaped RC walls.

An experimental study with many variables was carried out to investigate the effective width of simply supported composite beams (T and L sec. beams) with and without slab opening. Three full-scale composite slab models with six different carrier simply supported composite beams (three with T-sec. and three with L-sec.) with constant slab rectangularity were tested.� Each model was loaded by a uniform distributed load (within elastic behavior zone) then loaded by means of two-concentrated loads system acting at equal distances from supports till failure. One of them without slab opening and the others with two symmetric slab openings and constant opening position in direction parallel to main supporting beams longitudinal axes. In this research, the tested model features, materials properties and measurement instrumentations are described in brief. The maximum load carrying capacity; crack patterns, deflections at different positions and generated strains in form of estimated effective width were experimentally investigated. Interesting gained results were recorded such that more than 100% of slab effective width is preserved for interior supporting beams if the openings are away enough from carried composite slabs structural carried zones while only 70% was preserved for exterior ones. Also, concentrated loads manner reduced carried composite slab effective width to be85%in average of that recorded for equivalent distributed loads. Some conclusions and recommendations are introduced.

District Heating is a cornerstone for the decarbonisation of the heating and cooling sector in Europe. Nonetheless, this technology is currently absent in a majority of the continent’s urban areas, and hence the need for appropriate methods by which to estimate the cost, as well as underlying cost parameters, to assess the feasibility of developing district heating networks is of general interest. One key underlying cost parameter, the concept of Effective Width, which is the ratio between a land area and the trench length within that land area, is the focus quantity of this work. Effective Width enables a first order assessment of the total route length of pipes in a given urban area and, together with the average diameter of the pipes, allows an estimation of the investment cost of installing district heating pipes. However, initial implementations of the Effective Width have been based on rather limited empirical evidence, such as a small set of cases and often disregarding service pipes due to lack of data. Another shortcoming of previous studies is the extrapolation of established relations into more sparsely populated areas. By assembly of a richer database, which contains building data, heat consumption data in the supplied areas, as well as actual network information (numerical and geographical), provided by several district heating companies in Denmark and Sweden, the objectives of this study are twofold: first, to improve the general understanding of Effective Width and its relation to building density, and secondly, to study the particular case of sparse areas. The results of this study provide new insight to enhance our understanding of the Effective Width concept which may facilitate better assessments of future district heating systems.

Since the introduction of the effective width concept for the estimation of the linear heat density, it has been frequently used by researchers to calculate district heating distribution grid costs in pre-feasibility phases. Some researchers however, still prefer using a detailed modelling approach to get reliable results. This paper aims at highlighting advantages, disadvantages and challenges of using effective width concept for calculation of district heating distribution grid costs in comparison to a detailed, optimisation-based modelling approach such as DHMIN. The outcomes of this paper reveal that although there are differences in obtained indicators such as trench length or distribution gird costs, both approaches deliver very similar patterns in different areas with various heat demand densities and plot ratios. Furthermore, it was revealed that for getting reliable results for a given case study, the input parameters and cost components should always be tuned to that case study regardless of the approach that is used.

Analytical theories related to the buckling criterion and strength of thin-walled structures are classified into flat plate and cylindrical shell theories and others (conical shell and spherical shell). To discuss the accurate predictions for the ultimate load-bearing capacities (ULBCs) of thin-walled steel (TWS) composite members under longitudinal compression and solve the long-standing problem of the different effective width (EW) definitions under different main TWS structural specifications, a simple model of a flat element supported in parallel by two cylindrical shell elements (corner ridgelines) on both longitudinal sides was analyzed. In addition, a simplified method to evaluate the reduction factor of the postbuckling ULBC caused by the initial imperfections was developed. The rational results for releasing additional anti-buckling functions of the ridgeline revealed herein are expected to be beneficial to the structural lightweight optimization for not only civil and construction engineering but also other broad areas such as spacecraft and aircraft engineering.

The production of plastic material continues to increase around the world. Consequently, large amount of waste plastic is generated. This will lead to environmental concern due to its disposal. In order to reduce the environment effects and cost, waste plastic can be recycled and utilized in other applications including construction. This paper investigated the flexural behavior of non-structural concrete beams containing waste plastic meshes as a replacement of traditional steel reinforcement. To achieve this objective, beams with steel reinforcing bars and waste plastic sheets with different effective widths and patterns were prepared. After 28 days of curing, the beams were subjected to an increasing load until failure and the central deflection was measured at each load increment. Furthermore, a numerical analysis was performed on the specimens using ABAQUS software. This will allow the comparison between the experimental and numerical results. The experimental data indicated that using plastic sheets improved the flexural toughness and ductility of concrete beams. Additionally, correlations were carried out between the ultimate capacity of the beams, the flexural toughness and the effective width of the plastic meshes. As the effective mesh width increased, the flexural toughness and ultimate capacity of the concrete beams increased. The results of this investigation will allow greater utilization of waste plastic in construction activities.

Intensification of coal mining from mine seams of 0.55–1.20 m thick requires increasing efficiency of loose coal loading that may be achieved by selecting the optimal parameters of auger operating device of a shearer. The most reliable way to determine effect of the auger parameters on the energy parameters of the shearer operation is experimental research in actual operating conditions. As the subjects of the research, we selected up-to-date UKD400 and UKD200-500 shearers, operating in representative conditions of the Krasny Partizan mine of SE SVERDLOVANTRATSIT and Ternovskaya mine of DTEK PAVLOGRADUGOL PJSC. An adaptive method for specific mining operating conditions is proposed for determining the specific energy consumption of the shearers on material disruption and loading for thin seams in actual operating conditions based on fixing the values of currents of the cutting drive motors. Based on processing of the experimental data, an indicative dependence of the power for rock mass loading on the feed rate and the effective width of the operating device is determined. Increasing the auger effective width results in increasing the loading power and specific energy consumption. At the same time, the higher the shearer feed rate, the greater the growth of the loading power and specific energy consumption. This is due to the beginning of the process of loose rock mass circulation, and the larger the auger effective width, the more intensive the circulation process, and at the lower feed rate of the shearer the process starts. A method is proposed for selecting the auger optimum effective width based on the criteria of minimum specific energy consumption and maximum commercial productivity.

ABSTRACT: Bridges are structures built to overcome obstacles and allow continuity of transport routes. In the search for efficient construction systems, steel-concrete composite structures, especially box girder bridges, emerged. The American AASHTO and European EN 1994-2-2 standards present design procedures for this type of bridge, but there are still doubts about which portion of the concrete slab contributes to each web strength in composite section (effective width). The present paper aims to evaluate, by numerical analysis in the Abaqus® software, the concrete slab effective width and to verify whether the expressions for its calculation in composite I-girder bridges are valid for box girder sections. After analyzing the results, it was found that the standards recommendations for composite I-girder cannot be applied directly to box girders. Finally, based on the numerical analysis, an equation was proposed to calculate the effective width of steel-concrete composite box girder bridges.

Abstract Most of the engineering problems involving structural elements of steel-concrete composite beam type are approximations of the structural problem involving concrete plates connected by connectors to steel beams. Technical standards allow the replacement of the concrete plate element by a beam element by adopting a reduction in the width of the plate element known as effective width. The effective width is obtained, in most technical norms, taking into account only the parameters of beam span length and distance between adjacent beams. Numerical and experimental works found in the literature show that this effective width depends on several other parameters, such as the width and thickness of the concrete slab, and the type of loading. The objective of this work is to verify the influence of the partial interaction in the evaluation of the effective width of composite beams formed by a concrete slab connected to a steel beam with deformable connection, being used in numerical simulation three types of finite elements: a plate element for nonlinear analysis of the concrete slab; a bar element for non-linear analysis of beams with cross-section defined by a polygon; and an interface element which connects the plate and beam elements, simulating the deformation effect of the shear connectors. In the studied examples, it was found that the reduction of the shear connection stiffness at the interface between the concrete slab and the steel beam leads to a decrease in the shear lag effect and, consequently, makes the effective width of the concrete slab closer to the its real width. In another example, curves are constructed to define the effective width of a composite beam with medium stiffness. Considering maximum stresses and maximum displacements, these curves are obtained by forcing the equivalence of the approximate model with the model closest to the real problem.

This paper studies the effects of stiffeners on shear lag in steel box girders with stiffened flanges. A three-dimensional linear finite element analysis using STAAD.Pro V8i program has been employed to evaluate and determine the actual top flange stress distribution and effective width in steel box girders. The steel plates of the flanges and webs have been modeled by four-node isoparametric shell elements, while the stiffeners have been modeled as beam elements. Different numbers (4, 8, and 15) for the steel stiffeners have been used in this study to establish their effects on the shear lag and longitudinal stresses in the flange. Using stiffeners reduced the magnitude of the top flange longitudinal stresses about 40%, but didnt affect the shear lag.

Queue length of vehicles due to stopping of a public vehicle, cause traffic jam. To relate the influence of vehicle volume, by effective width of the road and public vehicle’s stopping time to queue length, linear regression model is used. The result of analysis by states that the best solution to reduce the queue length of vehicle is controlling the public vehicle to stop at the right place and setting a limit of stopping time. Abstract in Bahasa Indonesia : Panjangnya deretan kendaraan jalan raya akibat berhentinya angkutan umum adalah salah satu bentuk kemacetan di jalan raya. Analisa pengaruh panjang antrian ini terhadap volume kendaraan yang lewat, lebar efektif jalan dan waktu henti angkutan umum, menggunakan metode pendekatan dengan cara regresi linier. Hasil analisa mendapatkan solusi yang terbaik berupa penertiban angkutan umum agar berhenti pada tempatnya dan dengan cara yang benar, sekaligus pembatasan lamanya waktu berhenti angkutan kota. Kata Kunci: lebar efektif, panjang antrian, volume kendaraan, waktu henti kendaraan umum

This paper studies the effects of stiffeners on shear lag in steel box girders with stiffened flanges. A three-dimensional linear finite element analysis using STAAD.Pro V8i program has been employed to evaluate and determine the actual top flange stress distribution and effective width in steel box girders. The steel plates of the flanges and webs have been modeled by four-node isoparametric shell elements, while the stiffeners have been modeled as beam elements. Different numbers (4, 8, and 15) for the steel stiffeners have been used in this study to establish their effects on the shear lag and longitudinal stresses in the flange. Using stiffeners reduced the magnitude of the top flange longitudinal stresses about 40%, but didn’t affect the shear lag.

The paste fiber reinforced composite material (hereinafter referred to as FRP) U-shaped hoop of reinforced concrete beams interfacial debonding is an important reinforcement technology research. For the effective width of the CFRP U-shaped hoop reinforcement, it is still a lack of in-depth research, only relying on the test research huge workload, this article (ANSYS) and the numerical simulation in the whole process of the shear load release properties of finite element calculation software. According to the results of finite element analysis, the author studied the CFRP U-shaped hoop to increase the width of the shear capacity of reinforced concrete beams by the impact.

This paper presents the study of an analytical model to estimate the strength of a thin-walled channel steel section beam subjected to axial-compressive loads. The model is based on two different methods of analysis, which are performed by analysing a plastic failure mechanism and elastic behaviour of the beam. These analytical methods can be used to establish plastic-unloading and elastic-inclining-theoretical load-deflection behaviour of the beam. Meanwhile, the axial-compressive strength of the beam is estimated by directly measuring the value of load at an intersection point between two different curves of the theoretical load-deflection behaviour. The accuracy of using this analytical model is also verified by comparing its estimated data of the strength to the one obtained from a number of tests on 38 specimens of thin-walled channel steel section under the test loads of axial compression. It is clearly shown that deviation of the analytical data from the experimental one is still scattered within acceptable limits of ± 20%. A statistical analysis of the scattered data indicates that its mean value is 1.03 with standard deviation of 0.058. This certainly means that the estimated strength, on average, displaces from the actual one by 3% and mostly tends to be conservative.