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This paper aims to present the results of an extensive experimental programme on the fire behaviour of timber beam-to-column shear connections, loaded perpendicularly to the grain.

The experimental programme comprised tests at normal temperature and loaded fire resistance tests on beam-to-column connections in shear. Twenty-four full-scale tests at normal temperature were performed covering nine different connection typologies, and 19 loaded fire resistance tests were conducted including 11 connections typologies.

The results of the fire resistance tests show that the tested typologies of steel-to-timber dowelled connections reached more than 30 and even 60 minutes of fire resistance. However, aspects such as a wider gap between the beam and the column, reduced dowel spacing, and the presence of reinforcement with self-drilling screws all have a negative influence on the fire resistance.

The experimental programme addressed the fire behaviour of timber beam-to-column shear connections loaded perpendicularly to the grain in a systematic way testing a wide range of common connection typologies significantly enlarging their experimental background.

This paper aims to investigate and assess a perspective of combining high-strength-steel endplate with mild-steel beam and column in endplate connections.

First, experimental tests on high strength steel endplate connections were conducted at fire temperature 550°C and at an ambient temperature for reference.

The moment-rotation characteristic, rotation capacity and failure mode of high-strength-steel endplate connections in fire and at an ambient temperature were obtained through tests and compared with those of mild-steel endplate connections. Further, the provisions of Eurocode 3 were validated with test results. Moreover, the numerical study was carried out via ABAQUS and verified against the experimental results.

It is found that a thinner high-strength-steel endplate can enhance the connection’s rotation capacity both at an ambient temperature and in fire (which guarantees the safety of an entire structure) and simultaneously achieve almost the same moment resistance with a mild steel endplate connection.

In this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, are presented.

An analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections is presented. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors.

In this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, is presented. The required yield and plastic moments in this model are provided as an extension to Roark's relationships. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors. A reasonable agreement has been found between the analytical model results and the experimental/numerical modeling results.

This article is extracted from the author’s doctoral thesis, and all its achievements belong to the authors of the article.

In this study, the application of a novel combined steel curved damper (SCD) and steel plate shear wall (SPSW) system in the 5-, 10- and 15-storey steel moment-resisting frames (SMR) subjected to earthquake excitation has been investigated. The proposed system is called here as the SMR-WD (steel moment resisting–wall damper).

At the beginning of this research, an SMR-W and an SMR-D are separately modeled in ABAQUS software and verified against the available experimental data. After that, three different heights SMR-WD systems (5-, 10- and 15-storey) are designed and simulated. Then, their performances are examined and compared to the corresponding SMR-W under the effects of six actual earthquake records.

The obtained results show that the proposed system increases the mean values of the base shear for 5-, 10- and 15-storey SMR-WD equal to 27, 20.15 and 16.51%, respectively compared to the corresponding SMR-W. Moreover, this system reduces the drift of the floors so that the reduction in the average values of maximum drift for 5-, 10- and 15-storey SMR-WD is equal to 10, 7 and 29%, respectively with respect to the corresponding SMR-W. The results also reveal that the considered system dissipates more energy than SMR-W so that the increase in the mean values of the energy absorption for 5-, 10- and 15-storey SMR-WD is 30.8, 25.6 and 41.3%, respectively when compared to the SMR-W. Furthermore, it is observed that SMR-WD has a positive effect on the seismic performance of the link beams and panel zones of the frames. By increasing the height of the structure in the SMR-WD, the energy dissipation and base shear force increases and the drift of floors decreases. Hereupon, the proposed SMR-WD system is more useful for tall buildings than SMR-W frames.

For the first time, the application of a novel combined steel curved damper (SCD) and steel plate shear wall (SPSW) system in the 5-, 10- and 15-storey steel moment-resisting frames (SMR) subjected to earthquake excitation has been investigated.

This study aims to reveal more information and understanding on performance and failure mechanisms of high strength steel endplate connections after fire.

An experimental and numerical study on seven endplate connections after cooling down from fire temperature of 550°C has been carried out and reported herein. Moreover, the provisions of European design standard for steel structures, Eurocode 3, were validated with test results of high strength steel endplate connections.

In endplate connections, a proper design using a thinner high strength steel endplate can achieve the same failure mode, similar residual load bearing capacity and comparable or even higher rotation capacity after cooling down from fire. It is found that high strength steel endplate connection can regain more than 90 per cent of its original load bearing capacity after cooling down from fire temperature of 550°C.

The post-fire performance of high strength steel endplate connection has been reported. The accuracy of Eurocode 3 for endplate connections is validated against test results.

In fire condition, the time to failure of a timber connection is mainly reliant on the wood charring rate, the strength of the residual wood section, and the limiting temperature of the steel connectors involved in the connection. The purpose of this study is to experimentally investigate the effects of loaded bolt end distance, number of bolt rows, and the existence of perpendicular-to-wood grain reinforcement on the structural fire behavior of semi-rigid glued-laminated timber (glulam) beam-to-column connections that used steel bolts and concealed steel plate connectors.

In total, 16 beam-to-column connections, which were fabricated in wood-steel-wood bolted connection configurations, in eight large-scale sub-frame test assemblies were exposed to elevated temperatures that followed CAN/ULC-S101 standard time-temperature curve, while being subjected to monotonic loading. The beam-to-column connections of four of the eight test assemblies were reinforced perpendicular to the wood grain using self-tapping screws (STS). Fire tests were terminated upon achieving the failure criterion, which predominantly was dependent on the connection’s maximum allowed rotation.

Experimental results revealed that increasing the number of bolt rows from two to three, each of two bolts, increased the connection’s time to failure by a greater time increment than that achieved by increasing the bolt end distance from four- to five-times the bolt diameter. Also, the use of STS reinforcement increased the connection’s time to failure by greater time increments than those achieved by increasing the number of bolt rows or the bolt end distance.

The invaluable experimental data obtained from this study can be effectively used to provide insight and better understanding on how mass-timber glulam bolted connections can behave in fire condition. This can also help in further improving the existing design guidelines for mass-timber structures. Currently, beam-to-column wood connections are designed mainly as axially loaded connections with no guidelines available for determining the fire resistance of timber connections exerting any degree of moment-resisting capability.

Basically, connections are used to transfer the force supported by structural members to other parts of the structure. The flush end-plate bolted beam to column connection is one type that has been widely used because of its simplicity in fabrication and rapid site erection. The purpose of this study is to determine the moment-rotation curve, moment of resistance (MR) and mode of failure, and the results were compared with existing results for normal flat web connections.

In this study, the connection modeled was the flush end-plate welded with triangular web profile (TriWP) steel beam section and then bolted to a UKC column flange. The bolted flush end-plate semi-rigid beam to column connection was modeled using finite element software. The specimen was modeled using LUSAS 14.3 finite element software, with dimensions and parameters of the finite element model sizes being 200 × 200 × 49.9 UKC, 200 × 100 × 17.8 UKB and 200 × 100 with a thickness of 20 mm for the endplate.

It can be concluded that the MR obtained from the TriWP steel beam section is different from that of the normal flat web steel beam by 28%. The value of MR for the TriWP beam section is lower than that of the normal flat web beam section, but the moment ultimate is higher by 21% than the normal flat web. Therefore, it can be concluded that the TriWP section can resist more acting force than the normal flat web section and is suitable to be used as a new proposed shape to replace the normal flat web section for a certain steel structure based on the end-plate connection behavior.

As a result, the TriWP section has better performance than the flat web section in resisting MR behavior.

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 paper aims to predicting the behavior of welded angle connections (moment-rotation-temperature) in fire using artificial neural network 10.

An artificial neural networking model is described to predict the moment-rotation response of semi-rigid beam-to-column joints at elevated temperature.

Data from 47 experimental fire tests and verified finite element model are used for training and testing and validating the neural network models. The model’s predicted values are compared with actual test results. The results indicate that the models can predict the moment-rotation-temperature behavior of semi-rigid beam-to-column joints with very high accuracy. The developed model can be modified easily to investigate other parameters that influence the performance of joints in fire.

The results indicate that the models can predict the moment-rotation-temperature behavior of semi-rigid beam-to-column joints with very high accuracy. The developed model can be modified easily to investigate other parameters that influence the performance of joints in fire.

The purpose of this paper is to show that the growing global trend of quality assurance indicates the potential of precast concrete (PC) to improve construction quality and productivity, reduce wasteful construction, and achieve design standardization and to accelerate construction time. However, its current approach for dynamic characteristics, such as stiffness and displacement on beam-column connection system design, is not effective in achieving the required quality and operational requirements.

A design tool based on the literature and data analysis in product planning and safety is proposed for the practice of PC building construction.

The results reveal the need for improvement of PC building performance in the construction industry, especially for the beam-column connection system. The issues include improper design, improper specification and defective concrete and steel components compared to other manufacturing methods.

A novel and sophisticated technique based on physical internet-enabled building information modeling (PI-BIM) is proposed to improve the planning process and safety for PC buildings in Malaysia.