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An h‐adaptive finite element code for solving coupled Navier‐Stokes and energy equations is used to solve the thermally driven cavity problem for Rayleigh numbers at which no steady state exists (greater than 1.9 × 10⁸). This problem is characterised by sharp thermal and flow boundary layers and highly advection dominated transport, which normally requires special algorithms, such as streamline upwinding, to achieve stable and smooth solutions. It will be shown that h‐adaptivity provides a suitable solution to both of these problems (sharp gradients and advection dominated transport). Adaptivity is also very effective in resolving the flow physics, characterised by unsteady internal waves, are calculated for three Rayleigh numbers; 2 × 10⁸, 3 × 10⁸ and 4 × 10⁸ using a Prandtl number of 0.71 and results are compared with other published results.

An h‐adaptive finite element code for solving coupled Navier‐Stokes and energy equations is used to solve the thermally driven cavity problem. The buoyancy forces are represented using the Boussinesq approximation. The problem is characterised by very thin boundary layers at high values of Rayleigh number (>10⁶). However, steady state solutions are achievable with adequate discretisation. This is where the auto‐adaptive finite element method provides a powerful means of achieving optimal solutions without having to pre‐define a mesh, which may be either inadequate or too expensive. Steady state and transient results are given for six different Rayleigh numbers in the range 10³ to 10⁸ for a Prandtl number of 0.71. The use of h‐adaptivity, based on a posteriori error estimation, is found to ensure a very accurate problem solution at a reasonable computational cost.

Reinforced concrete slabs in fire have been heavily studied over the last three decades. However, most experimental and numerical work focuses on long-duration uniform exposure to standard fire. Considerably less effort has been put into investigating the response to localised fires that result in planarly non-uniform temperature distribution in the exposed elements.

In this paper, the OpenSees for Fire framework for modelling slabs under non-uniform fire exposure is presented, verified against numerical predictions by Abaqus and then validated against experimental tests. The thermal wrapper developed within OpenSees for Fire is then utilised to apply localised fire exposure to the validated slab models using the parameters of an experimentally observed localised fire. The effect of the smoke layer is also considered in this model and shown to significantly contribute to the thermal and thus thermo-mechanical response of slabs. Finally, the effect of localised fire heat release rate (HRR) and boundary conditions are studied.

The analysis showed that boundary conditions are very important for the response of slabs subject to localised fire, and expansive strains may be accommodated as deflections without severely damaging the slab by considering the lateral restraint.

This work demonstrates the capabilities of OpenSees for Fire in modelling structural behaviours subjected to non-uniform fire conditions and investigates the damage pattens of flat slabs exposed to localised fires. It is an advancing step towards understanding structural responses to realistic fires.

Perforated composite beams are an increasingly popular choice in the construction of buildings because they can provide a structurally and materially efficient design solution while also facilitating the passage of services. The purpose of this paper is to examine the behaviour of restrained perforated beams, which act compositely with a profiled slab and are exposed to fire. The effect of surrounding structure on the composite perforated beam is incorporated in this study using a virtual hybrid simulation framework. The developed framework could also be used to analyse other structural components in fire.

A finite element model is developed using OpenSees and OpenFresco using a virtual hybrid simulation technique, and the accuracy of the model is validated using available fire test data. The validated model is used to investigate some of the most salient parameters such as the degree of axial and rotational restraint, arrangement of the openings and different types of fire on the overall fire behaviour of composite perforated beams.

It is shown that both axial and rotational restraint have a considerable effect on time-displacement behaviour and the fire performance of the composite perforated beam. It is observed that the rate of heating and the consequent development of elevated temperature in the section have a significant effect on the fire behaviour of composite perforated beams.

The paper will improve the knowledge of readers about modelling the whole system behaviour in structural fire engineering and the presented approach could also be used for analysing different types of structural components in fire conditions.

In present study, a full-scale testing of reinforced concrete (RC) frame sub-assemblage has been investigated under fire subsequent to simulated seismic loading. First part of the sequential loading consisted of a quasi-static cyclic lateral loading corresponds to life safety level of structural performance on the test frame. In the second part of the test, a compartment fire was ignited to the pre-damaged test frame for one hour duration simulating fire following earthquake (FFE) scenario. The results showed that the first cracking was observed at the end joints of the roof beams after the frame experienced a 30 mm cyclic lateral displacement. One hour heating and eleven hour cooling was tracked and temperatures were recorded. A knocking sound was heard from the fire compartment after 5 minutes of the fire ignition. An excessive degradation of the concrete material at a number of locations of the frame sub-assemblage was observed during visual inspection after the fire test. The Nondestructive tests (NDT) were also conducted to ascertain the damage in the RC frame at the various stages of loading. The test results developed an understanding of the behaviour of RC frame sub-assemblage in FFE.

Evaluation of mechanical properties of undamaged and damaged steel rebars at elevated temperature finds its applications in development of steel material models likely to be used in designing reinforced concrete structural members subjected to earthquake triggered fire. In the present experimental investigation, 84 rebar specimens (cylindrical) of length 700 mm and diameters 8 mm, 10 mm, 16 mm and 20 mm were tested. Test specimens were prepared from the materials used in construction of full-scale reinforced concrete frame subjected to earthquake and fire. The specimens were initially stressed to a certain known limit (0.58 times yield stress f_y) to simulate damage caused by an earthquake. After inducing the damage, they were exposed to a desired temperature level (20 °C, 250 °C, 500 °C and 750 °C) in a circular furnace arrangement coupled with a 400 kN universal testing machine. The temperature was sustained inside the furnace for about 30 minutes to ensure a steady state heat transfer inside the specimen. The bars were then tested under uniaxial tensile loading conditions to failure. The elongation was recorded by using two LVDTs fixed between gauge lengths of 265 mm at the mid-height. Results obtained in the tests were utilized to carry out multiple linear regression analysis and propose constitutive models for damaged steel rebars and various relationships: Tensile Strength, Peak-Strain, Elongation and Elastic Modulus vs. Temperature, Stress vs. Strain at elevated temperatures.

This study aims to examine Islamic banks’ (IBs’) obligations to uphold society’s moral and ethical dimensions. Furthermore, it explores the perspectives of practitioners and Shariah scholars on the role of IBs as agents to advance social and ethical well-being.

Qualitative methodology, with constructivist philosophy, was used. Semi-structured interviews were conducted with Shariah scholars and Islamic banking officials in Pakistan. The thematic analysis uncovered diverse dimensions catering to fulfill the requirements of social and ethical upliftment of society.

The study reveals discrepancies in the perception of IBs’ advisory board members and managers regarding the social responsibilities of IBs. Results show that practitioners of IBs disregard the overall societal welfare upliftment and faith and spiritual upliftment as a responsibility of IBs. However, they consider the inclusiveness, transparency and assurance of Hifz-e-Maal (safeguarding the wealth) among the prime duties of IBs.

This study serves as a call for policymakers, emphasizing that, to achieve the desired social outcomes, it is imperative to address the perceptual inconsistencies among stakeholders of the Islamic financial system.

This study compels policymakers to confront perceptual inconsistencies in Islamic banking, advocating for regulations that guarantee wider societal welfare and spiritual advancement in addition to financial objectives.

This study could help broaden the understanding of the Islamic financial system, particularly the aspects that may hamper getting the desired results of this system.

OpenSees is an open-source object-oriented software framework developed at UC Berekeley. The OpenSees framework has been recently extended to deal with structural behaviour under fire conditions. This paper summaries the key work done for this extension and focuses on the validation and application of the developed OpenSees to study the behaviour of composite steel-concrete beams under fire conditions. The performance of the developed OpenSees are verified by four mechanical tests and two fire tests on simply supported composite beams. A parametric study is carried out using OpenSees to study the influence of boundary condition as well as composite effect of slab on the behavior of composite beams exposed to fire. The stress and strain along the beam section is output and compared with yield stress limit at elevated temperature to explain these influences in detail. The results show that the stress distribution in the web of the steel beam is more complex due to the support effects.

In this paper we report the progress of our work so far on extending of the OpenSees framework so that it can be used to model structures subjected to fire. The work has focussed on understanding the C++ based object oriented structure of the OpenSees framework, so that all developments remain consistent with it. New classes have been added to introduce temperature dependent material properties for steel and concrete materials. New element classes have also been added to analyse 2D truss and frame structures subjected to fire. This paper will provide an overview of the developments already implemented and present results from using the implemented code to solve a number of benchmark problems and from modelling real fire tests.

Three-dimensional (3D) printing technology allows geometric complexity and customization with a significant reduction in the structural environmental impact. Nevertheless, it poses a serious threat to the environment when organic binders are used. Binder jet printing of alkali-activated geopolymer precursor can represent a successful and environmental-friendly alternative.

The present work reports about the successful 3D printing of metakaolin-based alkali-activated concrete, with dimensional integrity and valuable mechanical behavior.

The geometric behavior was studied as a function of alkali activator flow rate, and the minimum geometric deviation with complete saturation was recorded at 103 mg/s. The printed specimen is characterized by a modulus of rupture as high as 4.4 MPa at 135 mg/s.

The 3D printed geopolymer-based concrete can be potentially used in a wide range of structural applications from construction to thermal insulation elements.

The analysis of the 3D geopolymer-based concrete printing system and material conducted in this paper is original.