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Concrete-filled hollow section (CFHS) is widely used in steel construction. The combination of concrete and steel decreases buckling and deformation of steel. However, studies reveal that using normal concrete increases the dead weight of a structure. Therefore, a lightweight concrete, such as foamed concrete (FC), is proposed to reduce the weight of the structure. The purpose of this study is to determine the strength of modified fibrous foamed CFHS (FCFHS).

Steel and polypropylene fibres were used with rice husk ash, and short column fibrous FCFHSs were tested under compression load. Greased and non-greased methods were adopted to determine bond strength and confining effect between steel and concrete.

Results indicate that the use of fibre in FCFHSs improves the strength of CFHS from 9% to 11%. The non-greased method confirms that an interaction exists between steel and concrete with a confinement coefficient of more than 2.0.

It can be shown that the modified fibrous foamed concrete can increase the strength of the concrete and can be used as concrete filled in steel construction industry.

The primary objective of this study is to produce one-way slabs made of LWFC with low density and sufficient compressive strength suitable for structural purpose then investigate their flexural behavior under various types of reinforcement and thickness of the slab and the influence of addition of PP fibers reinforcement on the mechanical behavior of reinforced concrete slabs. The specimens were tested using four-point loading. The results concerning load capacity, deflection and failure mode and crack pattern for each specimen were obtained. Also, an analytical investigation of PP fiber and GFG contribution on the flexural behavior of foamed concrete slabs is studied to investigate the significant role of PP fiber on the stress distribution in reinforced foam concrete and predict the flexural moment capacity.

The materials used in this study are cement, fine aggregate (sand), water, PP fibers, foaming agent, chemical additives if required, steel reinforcing rebars and glass fiber grid. The combination of these constituent materials will be used to produce foamed concrete in this research Then this study will present the experimental program of one-way foamed concrete slabs including slabs reinforced with GFR grids and another with steel reinforcements. The slabs will be tested in the laboratory under static loading conditions to investigate their ultimate capacities. The flexural behavior is to the interest of the slabs reinforced with GFR grids reinforcements in comparison with that of one with steel reinforcing rebars. Three groups are considered. (1) Group I: two slabs of PP fiber foamed concrete with minimum required reinforcements. (2) Group II: two slabs of PP fiber foamed concrete with glass fiber grids. (3) Group III: two slabs of PP fiber foamed concrete with the minimum required reinforcements and glass fiber grids.

The experimental results proved the effectiveness and efficiency of this the new system in producing a low density of concrete below 1900 kg/m³ had a corresponding strength of about 17 MPa at least. Besides, the presence of PP fibers had a noticeable improvement on the flexural strength values for all the examined slabs. It was found that the specimens reinforced with steel reinforcement mesh carried higher flexural capacity compared to these reinforced with GFG only. The specimens reinforced with GFG exhibited the lowest flexural capacity due to GFG separation from the concrete substrate. Also, an analytical investigation to predict the flexural strength of all tested specimens was carried out. The analytical results were agreed with the experimental results. Therefore, LWFC can be used as a substitute lightweight concrete material for the production of structural concrete applications in the construction industries today.

Foamed concrete is a wide field to discuss. To achieve the objectives of the project, the study is focused on the foamed concrete with the following limitations: (1) because the aim of this research is to produce foamed concrete suitable for structural purposes, it is decided to produce mixes within the density range 1300–1900 kg/m³. (2) Simply-supported slabs are of considered. (3) This study also looks out by using GFR and without it.

The main objectives of this study were producing structural foamed concrete slabs and investigate their flexural response for residential uses.

Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

ITALY Coating of metal with polyethylene. Polyethylene shows no particular degree of adhesiveness on metal surfaces. The following technique alone will give satisfactory results: an intermediate layer of polyvinyl alcohol or polyvinylformal or polyvinylbutyral is sprayed on with a flame spray gun, forming a crinkly coat. As soon as this undercoat has been applied the first polythene coat is sprayed on. This will homogenise the intermediate layers and give a smooth and even coat. The intermediate layer is sprayed on by blowing 80 to 100 g. of polyvinyl‐acetate powder per sq. m. of surface through a flame gun. The polythene is then applied in one, or preferably more, coats. Dry air is an excellent carrier for the powders, and the gun is operated with propane or hydrogen. —(G. Guzette, Ind. Vernice, 7 (12), 319–320.)

In the present article, the authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. Here, the main thrust is placed on the spalling phenomenon of concrete elements when exposed to elevated temperatures and fires.

In this context, it has been long established that prolonged thermal insult on concrete members will lead to egress of water, both physically bound as well as those present as water of hydration within the concrete matrix, in the form of steam through microchannels and associated pathways of least resistance, often resulting in the flaking of the surface of the structure. The latter process can ultimately lead to the exposure of the ferrous-based reenforcement elements, for instance, to higher temperatures, thus inducing melting. This, in turn, can result in substantial loss of strength and load-bearing capacity of the structural element that is already undergoing disintegration of its base matrix owing to heat/fire. Even though spalling of concrete structures has long been recognized as a serious problem that can often lead to catastrophic failure of infrastructures, such as buildings, bridges and tunnels, the utility of intumescent coating as a mitigation strategy is relatively new and has not been explored to its fullest possible extent. Therefore, in the latter parts of the review, the authors have endeavored to discuss the different types of intumescent coatings, their modes of actions and, in particular, their wider applicability in terms of protecting concrete elements from detrimental effects of severe or explosive spalling.

Given that spalling of concrete components is still a very serious issue that can result in loss of lives and destruction of critical infrastructures, there is an urgent need to formulate better mitigating strategies, through novel means and methods. The use of the intumescent coating in this context appears to be a promising way forward but is one that seems to be little explored so far. Therefore, a more systematic investigation is highly warranted in this area, especially, as the authors envisage a greater activity in the building and commissioning of more infrastructures worldwide incommensurate with augmented economic activities during the post-COVID recovery period.

The authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. The authors have also included the results from some recent tests carried out at the facilities using a newly commissioned state-of-the-art furnace.

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The purpose of this article is to reviews state-of-the-art developments in four-dimensional (4D) printing, discuss what it is, investigate new applications that have been discovered and suggest its future impact.

The article clarifies the definition of 4D printing and describes notable examples covering material science, equipment and applications.

This article highlights an emerging technology cycle where 4D printing research has gained traction within additive manufacturing. The use of stimuli-responsive materials can be programmed and printed to enable pre-determined reactions when subject to external stimuli.

This article reviews state-of-the-art developments in 4D printing, discusses what it is, investigates new applications that have been discovered and suggests its future impact.

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The purpose of this paper is to present an applied method to design the low-speed contact between a mass and surface of a beam using an analytical solution based on the first-order shear deformation beam theory. Also, a simulation of impact process is carried out by ABAQUS finite element (FE) code.

In theoretical formulation, first strains and stresses are obtained, then kinetic and potential energies are written, and using a combination of Ritz and Lagrange methods, a set of system of motion equations in the form of mass, stiffness and force matrices is obtained. Finally, the motion equations are solved using Runge–Kutta fourth order method.

The von Mises stress contours at the impact point and contact force from the ABAQUS simulation are illustrated and it is revealed that the theoretical solution is in good agreement with the FE code. The effect of changes in projectile speed, projectile diameter and projectile mass on the results is carefully examined with particular attention to evaluate histories of the impact force and beam recess. One of the important results is that changes in projectile speed have a greater effect on the results than changes in projectile diameter, and also changes in projectile mass have the least effect.

This paper presents a combination of methods of energy, Ritz and Lagrange and also FE code to simulate the problem of sandwich beams under low velocity impact.

A bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view is given. The bibliography at the end of the paper contains 1,726 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1996‐1999.