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This work was undertaken to compare the use of BS 8110 and Eurocode 2 in the design of structures and focused on outlining the relative gains and/or shortcomings of Eurocode 2 and BS 8110 under certain criteria which are loading, analysis, ease of use and technological advancement. To accomplish this, the analysis and design of the main structural elements in reinforced concrete building was undertaken using the two codes. A modest medium rise building was loaded using the two code and analyzed. Analysis was done using CSI start tedds to obtain the shear force and bending moment envelopes. For the beam, it was found that Eurocode 2 gave higher internal supports moments. For the case of maximum span moments and shear force values, the Euroode 2 values lagged behind. Column load and moments values were generally lower for Euroode 2. In summary, the comparative benefits of using Euroode 2 are that it is logical and organized, less restrictive and more extensive than the BS 8110. The new Eurocodes are claimed to be the most technically advanced code in the world and therefore should be adopted by Nigerian engineers. [ABSTRACT FROM AUTHOR]

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This paper describes the shrinkage of concrete made with recycled aggregates derived from demolition of concrete structures and is based on the 18 500 data matrix generated from 286 studies published in English from 38 countries since 1978. Relative to natural aggregates, the shrinkage of concrete increases at a decreasing rate with coarse recycled concrete aggregate content, giving an average increase of 33% at 100% natural aggregate replacement. This difference between the performance of the two concretes decreases with increasing ambient humidity and concrete strength. Increase in concrete shrinkage with fine and all-in recycled concrete aggregate and other recycled aggregates was found to be too high and variable to make them unsuitable for use in structural concrete. The assessment of the Eurocode 2 (2004), ACI 209·2R (2008) and Bažant-Baweja B3 (2000) models showed that, although the accuracy of the three models is similar, the shrinkage of concrete containing coarse recycled concrete aggregate is generally underestimated. Methods are proposed for determining the shrinkage of concrete made with coarse recycled concrete aggregate together with using Eurocode 2, as well as for minimising its effect on the shrinkage of concrete for a given strength and workability by reducing its cement paste content. [ABSTRACT FROM AUTHOR]

The objective of the paper is to analyze the efficiency of design methods proposed in different codes according to the load carrying capacity of concrete structures. In particular, three standard recommendations have been considered: the ACI 318 shear design model, the equation by Eurocode 2 and a new design procedure from Model Code 2010. In the paper the flexural concrete members, which are reinforced longitudinally but without transverse reinforcement, are considered. The design values of the load carrying capacity of such members obtained from these three codes were compared with experimental results. An advanced statistical analysis has been applied to predict of dependent variable (load carrying capacity of tested beams) and to perform a comparative analysis. On the basis of the analysis conclusions have been drawn according to the fit between the design methods and the test data. [ABSTRACT FROM AUTHOR]

The analysis of the mechanical behaviour of a reinforced concrete tie subjected to a monotonic loading in the stabilized cracking stage is performed here by way of a theoretical general model that considers the effect of the so-called Goto cracks (secondary cracks). It is shown, in particular, that the average bond stress along the transmission length depends not only on the concrete strength as assumed by the fib Model Code for Concrete Structures 2010, but also on reinforcement ratio and bar diameter. In this regard, tabulated theoretical values of the average bond stress are proposed as a function of the aforementioned parameters. Moreover, the secondary cracks reduce the effect of tension stiffening on the relative mean strain. On the basis of the main results obtained with the general model, some improvements are suggested for the calculation methods proposed by fib Model Code 2010 and Eurocode 2 concerning the average value of the bond stress and taking into account the influence of the secondary cracks on the mean deformation. An improved calculation method is therefore performed. Finally, the theoretical results of crack spacing and crack width obtained with the general and improved methods are compared with experimental data obtained from extensive research on RC ties. [ABSTRACT FROM AUTHOR]

The fib Model Code for Concrete Structures 2010 introduces a new design concept for punching shear based on critical shear crack theory. This paper presents and provides the background to the design provisions for punching shear according to fib Model Code 2010, Eurocode 2 and the corresponding German National Annex to Eurocode 2. The different punching shear design provisions are critically reviewed by means of parameter studies and a comparison of the calculated resistances and test results. The safety levels of the code provisions are verified and the influence of the different punching parameters on the calculated resistances is examined in detail. [ABSTRACT FROM AUTHOR]

The article provides basic information about the shrinkage of concrete and discusses the major impact on the size and course of the shrinkage. There are the guidelines to estimate the shrinkage strain of concrete bridge structures for the high tensile strength-SCI in accordance with PN-EN 1992-2. The article presents the results of experimental studies which aim was to analyze the course of shrinkage in two types of specimens made of different composition mixes. The studies have also made possible to verify the actual size of the shrinkage strain and designated ones on the basis of the PN-EN 1992-2. [ABSTRACT FROM AUTHOR]

Eurocode 2 consists of four parts that have to be applied in conjunction with the respective National Annexes of the CEN member states. The National Annexes were introduced, in particular, to maintain national safety levels and to account for regional aspects in the different states. The CEN (European Committee for Standardization) will revise and extend all structural Eurocodes by 2018. As part of that process, two main objectives for revising Eurocodes have been formulated: a reduction in the number of Nationally Determined Parameters (NDP) and improving the 'ease of use'. In order to reduce the number of NDP, improve the ease of use and allow for further harmonization without changing the main structure and the design models of Eurocode 2, the National Annexes of EN 1992-1-1 for the different CEN member states have been compared and analysed. Furthermore, the analysis of the National Annexes may help to identify some main aspects for the revision of Eurocode 2. This paper summarizes the analysis of the National annexes of EN 1992-1-1 and makes first proposals for further harmonization. [ABSTRACT FROM AUTHOR]

In this work, a FORTRAN-based computer program was developed to aid the design of reinforced concrete slabs to Eurocode 2 (EC 2) design requirements at constant reliability levels using First Order Reliability Method (FORM).The design variables for the design of the slab were considered random with safety indices calculated using FORM. It was shown among other findings that the FORM design procedure gave more economical designs considering the area of steel required and final depth of section, than the EC 2 design procedure when a target safety level of 3.0 was considered. Also, example of design using the program was included for various values of target safety indices at constant geometrical, loading and end condition of the slab. The developed program is therefore suitable for application. [ABSTRACT FROM AUTHOR]

Copyright of Beton- Und Stahlbetonbau is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An attempt is made to theoretically and experimentally verify the shrinkage curvature models presented in Eurocode 2 and BS 8110. These codes claim that the models originally derived and proven for uncracked sections are suitable, with modification, for predicting the behaviour of cracked sections, although this claim has never been proven experimentally. To achieve verification, an alternative theoretical approach is initially proposed in this paper. In this theoretical model, the effect of shrinkage, creep and the variation in the neutral axis position of the section are taken into account. The stresses developed in the steel and concrete at a cracked section according to this theoretical model are then applied to a finite-element (FE) model representing a portion of the beam from the crack to mid-way between the crack and an adjacent crack. Ultimately, the mean curvature is determined. Experimentally, pairs of beams were cast and subjected to a level of flexural loading to produce a stabilised crack pattern in the constant-moment zone. The behaviour of the beams was monitored for up to 180 days. For any pair of beams, one beam was cast using a high-shrinkage concrete and the other with a low-shrinkage concrete. Each concrete type, however, exhibits similar creep. Therefore, shrinkage curvature can be obtained by subtracting the long-term movements of one beam from the other. These experimentally defined curvatures were compared with the mean curvatures obtained from the FE analysis. The comparison showed reasonable agreement. The curvatures were also compared with uncracked and cracked curvatures predicted by the codes. The curvatures derived in this investigation fell within the boundaries of the uncracked and cracked curvatures predicted by the codes and, for the fully cracked case, the curvatures were closer to the uncracked boundary. [ABSTRACT FROM AUTHOR]

Copyright of Beton- Und Stahlbetonbau is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shrinkage plays an important, sometimes crucial, role in the design of many types of concrete structures as well as in their behaviour after construction. However, the uncontrolled strains are often larger than the expected values. As a matter of fact, there is as yet no perfectly satisfactory physical explanation for shrinkage. In this work, a large database has been set up for shrinkage testing performed by several research centres in Europe. On the basis of the statistical analysis of this database and by observing real structural behaviour, it becomes possible to investigate the current codes of practice regarding the computation of time-dependent shrinkage strains. As comparison with experimental tests has shown that predictions are often inaccurate, a correction factor is proposed in this work to improve the European Code, Eurocode 2, and lead to more satisfactory results. [ABSTRACT FROM AUTHOR]

The results of tests on cracking moment in steel fibre reinforced concrete beams based on waste sand are presented in this paper. The test defined cracking moment was compared with that calculated as proposed by Lok and Xiao, Tan, Paramasivam and Tan and by application of the methods contained in Eurocode 2 as well as in PN-84/B-03264. The best compatibility of the obtained test results with the calculated values was achieved for the Eurocode 2 method. [ABSTRACT FROM AUTHOR]

A number of studies in recent years have attempted to understand and calculate the shear strength of hollow-core slabs, but no consensus has been reached on this issue. The current design methods for hollow-core shear resistance are derived from experimental results and elastic theories that are not usually directly related to the behaviour at the ultimate limit state. Moreover, some manuals on this subject do not discuss anchorage failures, which although not common in this type of slab, may influence the shear strength. This paper considers the anchorage failure of strands using the concepts of Eurocode 2 and presents an analytical methodology for shear design based on the modified compression field theory (MCFT). Furthermore, the safety concepts of Eurocode 2 are properly presented and evaluated using the experimental data available in the literature. The proposed methodology is proved to be accurate and is simple enough for use in design. Comparisons with CSA A23.3 and Eurocode 2 are also shown. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the theoretical deflection behaviours of concrete beams reinforced with fibre-reinforced polymer (FRP) bars. The study evaluated the suitability of the present Eurocode 2 Part 1-1 deflection prediction method for FRP reinforced concrete (RC) flexural members and focuses on the appropriateness of using its modified form.

The structural life of a reinforced concrete beam has previously been defined by several stages which include loading of an intact structure to the serviceability stage, corrosion, load reduction before repair procedures, removal of contaminated concrete, patch repair and finally strengthening. Numerical simulations of this service life cycle without strengthening, where time-dependent effects such as creep and shrinkage were included in the constitutive models, were carried out using the phased analysis in the finite-element software Diana. The results of the simulations showed that the failure load is in good agreement with the failure load corresponding to the upper bound of the 95% confidence interval obtained in a previous probabilistic study based on the experimental results. Initial strains owing to shrinkage of the concrete and the repair material were implemented using the Model Code 1990 model (predefined in Diana) and a model for development of free shrinkage strain in beams exposed to one-side drying. This model was developed by Planas and Elices while the material parameters are based on Model Code 1990 or Eurocode 2. Total strains across the cross-section of the beam calculated in the finite-element analyses are compared with data that are available from the experimental study. [ABSTRACT FROM AUTHOR]

Eurocode 2 presents two alternative methods for accounting for arching action in beams. The simplest option is to reduce the component of shear force owing to loads applied within 2d of the support by the multiple a/2d (where a is the clear shear span and d is the effective depth). Eurocode 2 also allows short-span beams to be designed with the strut-and-tie method (STM), raising the question of which method to use. This paper presents a simple strut-and-tie model for short-span beams. The stress fields used in the STM are shown to be broadly consistent with those calculated with non-linear finite-element analysis. The STM is shown to give good predictions of shear strength, particularly when the concrete strength is calculated in accordance with the recommendations of Collins and Mitchell. The accuracy of the simplified design method in Eurocode 2 is shown to be highly dependent on the stirrup index. The paper also presents data from eight beams tested by the authors which show that aggregate fracture has little if any influence on the shear strength of short-span beams. [ABSTRACT FROM AUTHOR]

The current paper reviews existing design guidelines for strengthening beams in shear with carbon fibre reinforced polymer (CFRP) sheets and proposes a modification to Concrete Society Technical Report TR55. It goes on to present the results of an experimental programme which evaluated the contribution of CFRP sheets towards the shear strength of continuous reinforced concrete (RC) beams. A total of seven, two-span concrete continuous beams with rectangular cross-sections were tested. The control beam was not strengthened, and the remaining six were strengthened with different arrangements of CFRP sheets. The experimental results show that the shear strength of the beams was significantly increased by the CFRP sheet and that it is beneficial to orientate the FRP at 45° to the axis of the beam. The shear strength of FRP strengthened beams is usually calculated by adding individual components of shear resistance from the concrete, steel stirrups and FRP. The superposition method of design is replaced in Eurocode 2 by the variable angle truss model in which all the shear is assumed to be resisted by the truss mechanism. The current paper proposes a methodology for strengthening beams with FRP that is consistent with Eurocode 2. [ABSTRACT FROM AUTHOR]

The equivalent static system of basement walls under earth pressure is very important to determine the required wall thickness. Reversing moments due to eccentric loading at the top and bottom of the wall lead to lower design moments in the middle third of the wall. Eurocode 6 proposes an eccentricity of h/3 for the structural design of basement masonry walls. This limitation results from safety against lateral buckling. In contrast to the design of plain concrete basement walls, no value for the eccentricity is provided in Eurocode 2. However, finite-element simulations show that plain concrete has a sufficient ductility to enable reversing moments at the top and bottom of the wall due to eccentric loading. This is independent of the distortion of the basement floor and foundation. By estimating an equivalent static system with reversing moments a high reduction of the required wall thickness can be achieved. Furthermore, plain concrete walls are less labour- and material-intensive and therefore more economic than basement walls made of masonry or reinforced concrete. [ABSTRACT FROM AUTHOR]

Aiming to evaluate the minimum transversal reinforcement's influence on the behaviour of 6 reinforced concrete beams of 2,200 mm length and rectangular cross section of 250 mm height and width dimensions varying from 120 to 420 mm were cast and tested under shear at the Civil Engineering Laboratory of the Federal University of Para. Flexural reinforcement and the 2,000 mm span were kept constant. Results for failure loads and failure modes, steel and concrete strains and vertical displacements are presented and discussed. The experimental results showed that the NBR 6118 (2007) Code diverges significantly when the width varies. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including the verification of the shrinkage curvature models in Eurocode 2 (EC2), the goals of the structural Eurocodes project, and design code provisions for reinforced concrete design.

They have already become a new landmark: The six new water towers in the Al Jahra area in Kuwait City. Their mushroom-shaped water tanks were post-tensioned using DYWIDAG Strand Tendons. It goes without saying, that these buildings are of decisive importance for the inhabitants of cities in Kuwait (photo: DSI). [ABSTRACT FROM AUTHOR]