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The purpose of this study is to develop an analytical model that is capable of predicting the behavior of shear endplate beam-column assemblies when exposed to fire, taking into account the thermal creep effect.

An analytical model is developed and validated against finite element (FE) models previously validated against experimental tests in the literature. Major material and geometrical parameters are incorporated in the analysis to investigate their influence on the overall response of the shear endplate assembly in fire events.

The analytical model can predict the induced axial forces and deflections of the assembly. The results show that when creep effect is considered explicitly in the analysis, the beam undergoes excessive deformation. This deformation needs to be taken into account in the design. The results show the significance of thermal creep effect on the behavior of the shear endplate assembly as exposed to various fire scenarios.

However, the user-defined constants of the creep equations cannot be applied to other connection types. These constants are limited to shear endplate connections having the material and geometrical parameters specified in this study.

The importance of the analytical model is that it provides a time-effective, simple and comprehensive technique that can be used as an alternative to the experimental tests and numerical methods. Also, it can be used to develop a design procedure that accounts for the transient thermal creep behavior of steel connections in real fire.

In fire condition, the limiting temperature of a restrained steel beam depends on a few parameters, e.g. temperature distributions along and across the beam, beam’s load ratio and span length. The purpose of this study is to investigate the structural fire behaviour of axially restrained steel beams under different beam’s load ratios, taking into consideration the effect of the beam’s end connections configuration.

A three-dimensional finite element (FE) computer model has been developed to simulate the structural fire behaviour of axially restrained steel beams and their end connections. After successfully validating the developed model against the outcomes of the available large-size fire resistance experiments, the FE model has been used in a parametric study to investigate the beam’s load ratio effect on the behaviour of the axially restrained steel beams and their end connections.

The parametric study showed that increasing the beam loading level significantly increased the beam deflections at elevated temperatures; where, increasing the beam’s load ratio from 0.5 to 0.9 reduced the beam fire resistance by about 100 s. In contrast, decreasing the beam’s load ratio from 0.5 to 0.3 allowed the beam to easily achieve a 30-min fire resistance rating with no fire protection applied.

Experimental parametric studies are difficult to control in a laboratory setting and are also expensive and time consuming. Therefore, the reasonable accuracy of the validated FE model in reproducing the experimental fire behaviour of steel beams and their end connections makes it a very useful tool for both numerical and analytical studies.

This study aims to develop a rational model to predict the thermal axial forces developed in shear tab connections with composite beams when subjected to transient-state fire temperatures.

Finite element (FE) models are first developed in ABAQUS and validated against experimental data available in the literature. Second, a parametric study is conducted to identify the major parameters that affect the behavior of shear tab connections with composite beams in the fire. This includes beam length, shear tab thickness, shear tab location, concrete slab thickness, setback distance and partial composite action. A design-oriented model is developed to predict the thermal induced axial forces during the heating and cooling phases of a fire event. The model consists of multi-linear springs that can predict the stiffness and strength of each component of the connection with the composite beam.

The FE results show that significant thermal axial forces are generated in the composite beam in the fire. This is prominent when the beam bottom flange comes in contact with the column. Fracture at the toe of the welds governs the behavior during the cooling phase in most FE simulations. Also, the rational model is validated against the FE results and is capable of predicting the thermal axial forces developed in shear tab connections with composite beams under different geometrical properties.

The proposed model can predict the thermal axial force demand and can be used in performance-based approaches in future structural fire engineering applications.

The purpose of this paper is to report the first of four planned fire experiments on the 9.1 × 6.1 m steel composite floor assembly as part of the two-story steel framed building constructed at the National Fire Research Laboratory.

The fire experiment was aimed to quantify the fire resistance and behavior of full-scale steel–concrete composite floor systems commonly built in the USA. The test floor assembly, designed and constructed for the 2-h fire resistance rating, was tested to failure under a natural gas fueled compartment fire and simultaneously applied mechanical loads.

Although the protected steel beams and girders achieved matching or superior performance compared to the prescribed limits of temperatures and displacements used in standard fire testing, the composite slab developed a central breach approximately at a half of the specified rating period. A minimum area of the shrinkage reinforcement (60 mm²/m) currently permitted in the US construction practice may be insufficient to maintain structural integrity of a full-scale composite floor system under the 2-h standard fire exposure.

This work was the first-of-kind fire experiment conducted in the USA to study the full system-level structural performance of a composite floor system subjected to compartment fire using natural gas as fuel to mimic a standard fire environment.

This study aims to investigate the thermal creep behavior of steel frame assemblies with shear tab connections subjected to transient-state fire temperatures. Different key parameters are investigated to study their effect on the global response of the steel frames in fire.

Finite element (FE) models of connection assemblies are first analyzed using Abaqus under transient-state temperature conditions and validated against experimental work available in the literature. Upon acquiring the validated conditions, parametric studies are carried out to study the effect of key geometric and heating parameters on the overall response of the frame assembly to fire temperatures. Thermal creep material is also incorporated in the analyses through a user-defined subroutine, and a comparison between including and excluding creep material is illustrated to show the effect of thermal creep on the structural behavior.

The results reported herein indicate that having a rigid column increases the thermal-induced axial forces, thus increasing the development of thermal creep strains. Slow heating rates can cause axial stress relaxation in the restrained beam and increase the mid-span deflection and consequently the development of beam catenary action. The results also show that reaching higher initial cooling temperatures and having longer cooling phase durations result in more tensile forces at the end of the cooling phase.

Previous studies were limited to isolated steel connections under steady-state conditions. This study investigates the creep behavior of shear tab connection assemblies under transient-state conditions of fire when creep effects are explicitly considered. This can provide a rational and realistic assessment of the steel behavior in fire events.

In order to improve the robustness of bare-steel and composite structures in fire, a novel axially and rotationally ductile connection has been proposed in this paper.

The component-based models of the bare-steel ductile connection and composite ductile connection have been proposed and incorporated into the software Vulcan to facilitate global frame analysis for performance-based structural fire engineering design. These component-based models are validated against detailed Abaqus FE models and experiments. A series of 2-D bare-steel frame models and 3-D composite frame models with ductile connections, idealised rigid and pinned connections, have been created using Vulcan to compare the fire performance of ductile connection with other connection types in bare-steel and composite structures.

The comparison results show that the proposed ductile connection can provide excellent ductility to accommodate the axial deformation of connected beam under fire conditions, thus reducing the axial forces generated in the connection and potentially preventing the premature brittle failure of the connection.

Compared with conventional connection types, the proposed ductile connection exhibits considerable deformability, and can potentially enhance the robustness of structures in fire.

This paper gives a review of the finite element techniques (FE) applied in the analysis and design of machine elements; bolts and screws, belts and chains, springs and dampers, brakes, gears, bearings, gaskets and seals are handled. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of this paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An Appendix included at the end of the paper presents a bibliography on finite element applications in the analysis/design of machine elements for 1977‐1997.

The effect of bolt stripping failure on the ductility of steel end plate beam-column connections has received relatively little investigation to date. The objective with the present work is to establish a validated numerical model of end plate connections at elevated temperatures, which predicts the mechanical behaviour and failure modes observed in the experimental tests including the bolt stripping failure. Furthermore, the validated FE model was used to investigate the effect of stripping failure on both the rotational and load-bearing capacity of end plate connection.

The analysis was conducted on a validated numerical model of end plate connections at elevated temperatures, which predicts the mechanical behaviour and failure modes observed in the experimental tests including the bolt stripping failure. The material was modelled considering ductile damage initiation and evolution featured in ABAQUS/Standard.

This study demonstrates that thick end plates can prevent stripping failure which significantly improves the rotational capacity of the connection. This failure mode can develop readily with thin end plates; however the effect is often unrealistically mitigated through idealised experimental tests. The rotational capacity of a connection can be 5.0 times higher if stripping failure is avoided, particularly at elevated temperatures. Eurocode 3 part 1.8 does not consider the possibility of stripping failure when discussing the requirements for plastic analysis. It is concluded in the present study that by allowing for the possibility of bolt stripping, the mode of failure can often shift from end plate failure to bolt stripping, this in turn significantly reduces the connection rotational capacity.

The effect of bolt stripping failure on the ductility of steel end plate beam-column connections has received relatively little investigation to date.

In Southeast Asia, the renewable energy produced from hydropower systems has significant potential. Therefore, adequate development is needed to prevent future energy-related crises. This study, therefore, aims to determine the variations effects in geometry and the geometrical factors on turbine performance.

The developed aspects are selected to determine the blade shape, its number and multistage requirements. The study was conducted in 3D simulation, with Ansys software used to calculate a series of computational fluid dynamic problems. The aspect ratio applied in this study utilized the ratio of the overall diameter of the rotor height (D / H), which is 1.

The results showed that the highest C_p-max value, number of blades and stages were 0.2, two and three, respectively. Furthermore, these attributes combined to improve the performance of hydroturbines.

The research was fully conducted using numerical simulation, which requires sustainable research in the form of laboratory experiments. Also, pioneer experiments were conducted using benchmarking to ensure the results obtained are reliable.

Hydropower is one of the best renewable energy sources in Indonesia with a large potential in the archipelago and tropical countries due to rivers and various water sources. The current generated is a useful reference for Savonius design.

The originality of this study is to examine the three aspects of the geometry of the rotor, such as the number and shape of blades, as well as the stages in the same boundary conditions. Therefore, the comparison of the effects of changes in geometry on turbine performance is more acceptable and complete compared to the pioneer works, which focused on a parameter. This research combines several aspects to determine the effect of rivers and various water sources on the hydroturbine.

Few modeling approaches exist for cycloidal rotors because they are a prototypal technology. Thus, the purpose of this study was to develop new models for their analysis and validation. These models were used to analyze cycloidal rotors and a helicopter that uses them instead of a tail rotor.

Three different models were developed to study the aerodynamic response of cycloidal rotors. They are a simplified analytical model resolved algebraically; a multibody model resolved numerically; and an unsteady computational fluid dynamics (CFD) model. The models were validated using data coming from three different experimental sources, each with rotor spans and radii of roughly 1 m. The CFD model was used to investigate the influence of rotor arms. The efficiency and the stability of the rotor in different configurations were studied. An aeroelastic multibody simulation was used to verify the influence of flexibility on the rotor response.

The analyses suggested that cycloidal rotors can increase the efficiency of a helicopter at high velocities while flexibility reduces it and may lead to instabilities.

These models do not consider the effect of boundary layer friction on the trailing vortices generated by the rotor blades.

These models allow a four-step aerodynamic optimization procedure. First, a range of optimized configurations is obtained by the analytical model. Second, the multibody model refines that range. Third, the CFD model detects eventual problematic blade interactions.

The models presented should serve researchers and industrials looking for a means to measure the performance of cycloidal rotors concepts. The results presented also guide an initial cycloidal rotor design.