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A new model for handling non‐orthogonal cracks within the smeared crack concept is described. It is based on a decomposition of the total strain increment into a concrete and into a crack strain increment. This decomposition also permits a proper combination of crack formation with other non‐linear phenomena such as plasticity and creep and with thermal effects and shrinkage. Relations are elaborated with some other crack models that are currently used for the analysis of concrete structures. The model is applied to some problems involving shear failures of reinforced concrete structures such as a moderately deep beam and an axisymmetric slab. The latter example is also of interest in that it confirms statements that ‘reduced integration’ is not reliable for problems involving crack formation and in that it supports the assertion that identifying numerical divergence with structural failure may be highly misleading.

THE term “fabrication” is perhaps the best description of present methods of aircraft manufacture. Production, in the American sense of continuous output of standardised details and assemblies, is, fortunately for our versatile designers, a production ideal of the future. On the other hand, the term “jobbing shops” once applied to the industry by a well‐known designer is in most cases an unfair description.

In this study, the behavior of a multi-story flat plate structure during fire exposure is investigated using numerical simulations conducted with using ABAQUS software.

A three-dimensional finite element model is then carried out on the RC flat slab structure exposed to standard ISO-834 fire at different location arrangements. The model examines mid-span deflection, shear demand on the columns, bending moment and the membrane action of the floor slab.

The latter plays a main role to increase the capability and ductility of the slab at longer fire exposure to compensate the reduction in the flexural capacity. Also, shear demand in columns becomes bigger in cases of more than one surrounding slab exposed to fire at the same time.

This work focuses on the influence of the horizontal force on columns due to thermal expansion of slab which should be taken into account in the design of multistory multi-bay building considering it the same as the resulted horizontal force from the wind and seismic effect, the traveling fire and the restraint effect.

This paper aims to estimate the bearing capacity of a surface strip and circular footings lying on layered sand using numerical limit analysis.

Lower and upper bound limit analysis, as well as finite elements and second-order conic programming (SOCP), are used in this analysis. The yield criterion of Mohr-Coulomb is used to model soil behavior. Using this technique, stringent lower and upper bounds on ultimate bearing capacity can be achieved by assuming an associated flow law.

The obtained results indicate that the exact collapse load is typically being bracketed to within 6% about a mean of both the bounds. The obtained results are compared with the existing literature wherever applicable.

To the best of the authors’ knowledge, no study has used lower and upper bound limit analysis, as well as finite elements and SOCP, to estimate the bearing capacity of a surface strip and circular footings lying on layered sand.

Many problems are identified in the static analysis of a building based on ‘slabs, walls, columns’ by the classical method consisting of isolating the corresponding slab at each level and of subdividing it into finite elements by replacing walls and columns by localized fixed bearing points. Better adapted methods are indicated, particularly modelling the whole structure using ‘shell’ elements. A specially developed ‘slab, wall, column’ model is defined based on simplifying hypotheses which break down the effects of horizontal and vertical loads. The scope is precisely outlined and practical examples are given integrating the soil‐structure interaction and the placing of prestressing.

THE burr and its elimination are a major problem throughout the Aerospace industry. Removing burrs costs the industry millions of pounds each year. Burrs afflict a variety of processes. Punching, shearing, drilling and routing operations on metal all result in some degree of burr formation. Most manufacturers will need to eliminate burrs to ensure safer handling of parts and to improve the appearance and the quality of the finished product. Moreover, allowing burrs to remain will impair the functionality of the part. This is particularly true where metal parts are being manufactured to close tolerances such as the Aerospace industry.

This paper presents a review concerning the analytical and inverse methods of small punch creep test (SPCT) in order to evaluate the mechanical property of component material at elevated temperature.

In this work, the effects of temperature, specimen size and shape on material properties are mainly discussed using the finite element (FE) method. The analytical approaches including membrane stretching, empirical or semi-empirical solutions that are currently used for data interpretation have been presented.

The state-of-the-art research progress on the inverse method, such as non-linear optimization program and neutral network, is critically reviewed. The capabilities of the inverse technique, the uniqueness of the solution and future development are discussed.

The state-of-the-art research progress on the inverse method such as non-linear optimization program and neutral network is critically reviewed. The capabilities of the inverse technique, the uniqueness of the solution and future development are discussed.

The purpose of this study is to develop the performance model of buildings designed by the seismic code 2800 against the explosion wave and determination of safety distance.

Analytical models of three-, five- and ten story structures that used moment frame system and also a ten-storey building with shaer wall designed based on the seismic code 2800 in term of design and nonlinear analysis were generated for use with Perform-3D software. Extensive parametric analysis is executed on different explosive loads with 100, 500, 1,000 and 5,000 Trinitrotoluene, soil types 2 and 3, models eqs and eqbs, the number of story buildings and the effect of shear wall to determine the safety distance based on collapse threshold performance (CP) level criterion.

The results indicate that by increasing the explosives mass from 100 to 5,000 kg and the number of the stories three and five induce increasing the safety distance of CP level in buildings to 4.5 meter and 3 meter times, respectively. Ten-story structures modeled on shear wall show very good performance because of stiffness rising and high energy absorption. In addition, by increasing the stories from five to ten, the amount of the safety distance reduces the CP level to 3.9 meter times.

The results of this work are meaningful for explosion-resistant design and damage assessments of reinforced concrete moment framed structures subjected to explosive explosion.

Fig. 1 shows one of the many useful testing machines produced by W. and T. Avery Ltd. This particular apparatus illustrated, called the Avery Self‐Indicating Universal Testing Machine, was designed with the primary object in view of producing a tensile tester specially adapted for applying loads to aeroplane struts. The machine has been installed, among other places, at the works of Short Brothers (Rochester and Bedford) Ltd. It is arranged to take specimens up to a maximum length of 10 ft. and has a capacity of 50 tons.

The introduction of ever more complicated machinery and associated operating procedures is placing an increasing strain on the maintenance function. The options available to a company engaged in the manufacture of a range of sheet metal products, for which a flexible manufacturing facility has been installed, are examined. The introduction of this system has caused the company to examine its maintenance procedures, which are based on a traditional breakdown and repair approach, and has prompted an investigation into the possibility of implementing a condition based approach to maintenance. This investigation is presented here, together with a review of currently available options, and an outline of the planned move towards condition based maintenance.