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The purpose of this study is experimental research of the mechanical behavior of slab reinforced by cork composite patch submitted to an eccentric progressive compressive load applied to on impact rectangle of dimensions 28 × 23 cm². An analytical model and numerical modeling by finite elements are performed. This study is motivated by the evaluation of the effectiveness of this type of partial reinforcement to improve strength and ductility. The results are given by load-displacement curves, tensile damages cartography and ultimate strength histogram.

In experimental protocol, the following two parameters have been considered: the dimensions of the patch and the eccentricity of the load. The sections of the patches are calculated so that the ratio (XP/YP) patch is proportional to the ratio (LD/lD), with a step of 6 cm longitudinally and 4 cm transversely. Several dimensions patches are considered: (6 × 4) cm², (12 × 8) cm² and (18 × 12) cm². The eccentric punching loading test was performed with an eccentricity of the load (1/3) L’ and (2/3) L’ compared to the center of gravity of the slab. Taking into account the eccentricity of the load in estimating the rupture strength, the equations are developed. Thus, numerical simulations are carried, to extract tensile damages cartography.

The results show that the rupture begins with the appearance of cracks in the unreinforced area. For an eccentricity of 1/3L’, the best strength/section ratio is obtained for patch (12 × 8) cm², whereas for an eccentricity de 2/3L’, the patch (6 × 4) cm² gives a better resistance. The results highlight the influence of the composite on the ultimate load. The force-displacement relations are little modified in the elastic phase. The experimental results have been compared with the theoretical models showing a good correlation.

The strength and ductility are depended on the dimensions of the patch and the eccentricity of the load. The use of a patch to cover the most stressed area, in the event of an eccentric axial load is a very economical solution compared to the total reinforcement. The damage field shows that the evolution of cracks depends on dimensions and the position of the patch. Indeed, the eccentricity of the vertical load induces an additional bending moment that will influence the fracture surface. The rupture load and ultimate displacement increase with the surface of the patch.

This paper aims to study the influences of eccentricity on the fastener load and bearing strength of the eccentric connection in the aircraft structure.

The special experiment is designed for the researches. The fastener loads of the eccentric connection are gained by using the derived formulas and numerical analysis, and the fastener load rules is verified by the experiment. The bearing strength of the eccentric connection is investigated by the experiments under different eccentricities compared with that gained from the experiment.

The study results are summarized as follows. Magnitude of the fastener load in the eccentric connection is greatly affected by distance from the fastener to the centroid of the fastener cluster and that from the fastener to the concentrated load. With the increase of eccentricity of the homolateral concentrated load, the fastener load increases, and difference of the fastener loads becomes larger, forming the short plate effect of the bucket. It means that fastener with the maximum load (the shortest plate of the bucket) leads to decrease of the bearing strength of the eccentric connection (the capacity of the bucket).

The investigation on the influence of eccentricity on the bearing strength of eccentric connection is firstly presented. The vector expression of the fastener load in eccentric connection is firstly derived. And the influencing mechanism of the fastener load on the bearing strengths of the different eccentric connections is demonstrated. The study results can provide guidance for the structure design of the eccentric connection.

Advanced fibre-reinforced polymer (FRP) composites have been increasingly used over the past two decades for strengthening, upgrading and restoring degraded civil engineering infrastructure. Substantial experimental investigations have been conducted in recent years to understand the compressive behaviour of FRP-confined concrete columns. A considerable number of confinement models to predict the compressive behaviour of FRP-strengthened concrete columns have been developed from the results of these experimental investigations. The purpose of this paper is to present a comprehensive review of experimental investigations and theoretical models of circular and non-circular concrete columns confined with FRP reinforcement.

The paper reviews previous experimental test results on circular and non-circular concrete columns confined with FRP reinforcement under concentric and eccentric loading conditions and highlights the behaviour and mechanics of FRP confinement in these columns. The paper also reviews existing confinement models for concrete columns confined with FRP composites in both circular and non-circular sections.

This paper demonstrates that the performance and effectiveness of FRP confinement in concrete columns have been extensively investigated and proven effective in enhancing the structural performance and ductility of strengthened columns. The strength and ductility enhancement depend on the number of FRP layers, concrete compressive strength, corner radius for non-circular columns and intensity of load eccentricity for eccentrically loaded columns. The impact of existing theoretical models and directions for future research are also presented.

Potential researchers will gain insight into existing experimental and theoretical studies and future research directions.

In order to understand the status of the bridge reinforcement process, the construction process monitoring of the reinforced bridge is carried out. The T-beam bridge was tested using the truck loading test. The displacements and concrete strains of the bridge at mid-span were measured during the test.

This paper describes an innovative technique, external prestressing, used to strengthen a 36-year-old prestressed T-beam bridge. This paper introduces the construction process of the prestressed reinforcement method, and makes a theoretical analysis of the reinforced bridge through the establishment of the reinforcement model.

This study showed that the structural capacity and performance of the bridge were enhanced with externally prestressed steel strand strengthening.

The innovative reinforcement method of prestressed T-shaped bridge is put forward, which has guiding significance for similar bridge reinforcement and maintenance.

This is the final part of the article by Gerhard H. Junker of the European Research and Engineering Standard Pressed Steel Co, Unbrako. Previous parts have covered mechanism of self loosening, design to prevent self‐loosening and test methods.

Concrete-filled steel hollow (CFHS) column is an innovation to improve the performance of concrete or steel column. It is believed to have high compressive strength, good plasticity and is excellent for seismic and fire performance as compared to hollow steel column without a filler.

Experimental and numerical investigation has been carried out to study the performance of CFHS having different concrete in-fill and shape of steel tube.

In this paper, an extensive review of experiment performed on CFHS columns at elevated temperature is presented in different types of concrete as filling material. There are three different types of concrete filling used by the researchers, such as normal concrete (NC), reinforced concrete and pozzolanic-fly ash concrete (FC). A number of studies have conducted experimental investigation on the performance of NC casted using recycled aggregate at elevated temperature. The research gap and the recommendations are also proposed. This review will provide basic information on an innovation on steel column by application of in-filled materials.

Design guideline is not considered in this paper.

Fire resistance is an important issue in the structural fire design. This can be a guideline to define the performance of the CFHS with different type of concrete filler at various exposures.

Utilization of waste fly ash reduces usage of conventional cement (ordinary Portland cement) in concrete production and enhances its performance at elevated temperature. The new innovation in CFHS columns with FC can reduce the cost of concrete production and at the same time mitigate the environmental issue caused by waste material by minimizing the disposal area.

Review on the different types of concrete filler in the CFHS column. The research gap and the recommendations are also proposed.

Strain gauge loadcells have been used for many years to measure the contents weight of tanks, hoppers and the many various specialist processing vessels found in industrial manufacturing processes. Many of these applications have been extremely successful, providing the user with accurate and repeatable measurements with which to monitor and control chemically reactive, sometimes complex, blending operations. The benefits of a non‐contact measurement which is a direct indication of weight are self evident and have brought a reduction in manufacturing costs and improvement of product quality to those companies which have correctly applied the technique.

Investigate the fire performance of eccentrically loaded concrete partially encased column (PEC), using the advanced calculation method (ANSYS 18.2, 2017) and the simple calculation method in Annex G of Eurocode 4 (EN 1994-1-2, 2005). This work examines the influence of a range of parameters on fire behaviour of the composite column including: eccentricity loading, slenderness, reinforcement, fire rating and fire scenario. In this study, ISO-834 (ISO834-1, 1999) was used as fire source.

Currently, different methods of analysis used to assess the thermal behaviour of composite column exposed to fire. Analytical method named simplified calculation methods defined in European standard and numerical simulations named advanced calculation models are treated in this paper.

The load-bearing capacity of the composite column becomes very weak in the presence of the fire accident and eccentric loading, this recommends to avoid as much as possible eccentric loading during the design of construction building. The reinforcement has a slight influence on the temperature evolution; moreover, the reinforcement has a great contribution on the load capacity, especially in combined compression and bending. When only the two concrete sides are exposed to fire, the partially encased composite column presents a high load-bearing capacity value.

The use of a three-dimensional numerical model (ANSYS) allowed to describe easily the thermal behaviour of PEC columns under eccentric loading with the regard to the analytical method, which is based on three complex steps. In this study, the presence of the load eccentricity has found to have more effect on the load-bearing capacity than the slenderness of the composite column. Introducing a load eccentricity on the top of the column may have the same a reducing effect on the load-bearing capacity as the fire.

Microfocussed ion guns. A range of Microfocussed ion guns is available from VG Ionex which addresses a growing interest in many exciting new fields such as high resolution SIMS analysis, micro‐machining, ion beam lithography and sub‐micron surface engineering. The guns produce intense and highly stable beams with spot sizes down to less than 500 Angstroms. The current densities produced are in the range 1 Amp.cm−2. Gallium is the most popular source material but alternative metals and alloys are available for special applications. The guns are available as separate items or as part of complete systems.

The problems of achieving accurate temperature profiles in large scale and difficult environments like paint manufacture, are solved by the Distributed Temperature Sensor (DTS) from York Ltd.