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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.

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.

This work examines the effects of strain rate on the effective yield strength of high-strength steel at elevated temperatures, through tensile coupon tests at various strain rates, to propose appropriate reduction factors considering the strain rate effect.

The stress–strain relationships of 385 N/mm2, 440 N/mm2 and 630 N/mm2-class steel plates at elevated temperatures are examined at three strain rate values (0.3%/min, 3.0%/min and 7.5%/min), and the reduction factors for the effective yield strength at elevated temperatures are evaluated from the results. A differential evolution-based optimization is used to produce the reduction-factor curves.

The strain rate effect enhances with an increase in the standard design value of the yield point. The effective yield strength and standard design value of the yield point exhibit high linearity between 600 and 700 °C. In addition to effectively evaluating the test results, the proposed reduction-factor curves can also help determine the ultimate strength of a steel member at collapse.

The novelty of this study is the quantitative evaluation of the relationship between the standard design value of yield point at ambient temperature and the strain-rate effect at elevated temperatures. It has been observed that the effect of the strain rate at elevated temperatures increases with the increase in the standard design value of the yield point for various steel strength grades.

THE previous articles in this series, concerning the titanium, magnesium and aluminium alloys, followed a very similar form, in that in each case consideration of the aircraft engineering applications was preceded by a metallurgical appreciation of the alloy systems under review. In the case of steels, a comprehensive article on similar lines would be nothing less than a monograph, and if steels are to be discussed within the space of a single article, then a quite different approach must be adopted. This review will not, then, examine steels generally in any great metallurgical detail, but will rather consider their special merits in aircraft engineering, particularly in the context of supersonic aircraft.

This article is written from the viewpoint of a structures engineer who has to make the best use of the materials available, rather than that of the metallurgist who aids their production or development.

The purpose of this study is to clarify both tensile and shear strength for self-drilling screws, which are manufactured from high-strength, martensitic-stainless and austenitic stainless-steel bars, and the load-bearing capacity of single overlapped screwed connections using steel sheets and self-drilling screws at elevated temperatures.

Tensile/shear loading tests for the self-drilling screw were conducted to obtain basic information on the tensile and shear strengths at elevated temperatures and examine the relationships between both. Shear loading tests for the screwed connections at elevated temperatures were conducted to examine the shear strength and transition of failure modes depending on the test temperature.

The tensile and shear strengths as well as the reduction factors at the elevated temperature for each steel grade of the self-drilling screw were quantified. Furthermore, either screw shear or sheet bearing failure mode depending on the test temperature was observed for the screwed connection.

The transition of the failure modes for the screwed connection could be explained using the calculation formulae for the shear strengths at elevated temperatures, which were proposed in this study.

This paper aims to present technical aspects of the assessment method and evaluation of fire damaged steel structures. The current work focuses on the behavior of structural normal steel (hot-rolled and cold-formed) and high-strength bolts after exposure to elevated temperatures. Information on stainless steel, cast iron and wrought iron is also presented.

Because of the complexity of the issue, an elaborate presentation of the mechanical properties influencing factors is followed. Subsequently, a wide range of experimental studies is extensively reviewed in the literature while simplified equations for determining the post-fire mechanical properties are proposed, following appropriate categorization. Moreover, the reinstatement survey is also comprehensively described.

Useful conclusions are drawn for the safe reuse of the structural elements and connection components. According to the parametric investigation of the aforementioned data, it can be safely concluded that the most common scenario of buildings after fire events, i.e. apart from excessively distorted structures, implies considerable remaining capacity of the structure, highlighting that subsequent demolition should not be the case, especially regarding critical infrastructure and buildings.

The stability of the structure as a whole is addressed, with aim to establish specific guidelines and code provisions for the correct appraisal and rehabilitation of fire damaged structures.

The Carpenter Steel Company in the USA have announced developmet of a high‐strength, high‐ductility stainless steel. Called Carpenter Custom‐455, the new steel has a yield strength in excess of 240,000 p.s.i.—the highest in the stainless family.

The key purpose of conducting this review is to identify the issues that affect the structural integrity of pipeline structures. Heat affected zone (HAZ) has been identified as the weak zone in pipeline welds which is prone to have immature failures

In the present work, literature review is conducted on key issues related to the structural integrity of pipeline steel welds. Mechanical and microstructural transformations that take place during welding have been systematically reviewed in the present review paper.

Key findings of the present review underline the role of brittle microstructure phases, and hard secondary particles present in the matrix are responsible for intergranular and intragranular cracks.

The research limitations of the present review are new material characterization techniques that are not available in developing countries.

The practical limitations are new test methodologies and associated cost.

The fracture of pipelines significantly affects the surrounding ecology. The continuous spillage of oil pollutes the land and water of the surroundings.

The present review contains recent and past studies conducted on welded pipeline steel structures. The systematic analysis of studies conducted so far highlights various bottlenecks of the welding methods.

The purpose of this study is to put forward a high-strength bolt end-plate connection of prefabricated concrete beam-column joint and carry out the pseudo-static test.

ABAQUS finite element software is used to study the fire resistance performance of high-strength bolt end-plate prefabricated joint. This mainly considers the influence of axial compression ratio, screw preload, end-plate thickness and steel hoop thickness.

The results show that the thickness of end-plate and steel hoop has a certain effect on the fire resistance. The change of screw preload has little effect on the fire resistance limit. Compared with the cast-in-place concrete beam-column joint, the deformation trend of column-beam end of the fabricated joint is basically the same as that of cast-in-place joint.

To study the mechanical performance of this kind of joint more comprehensively, the finite element software is used to study the prefabricated concrete beam-column joint with end-plates, and the effects of axial compression ratio, screw preload, end-plate thickness and steel hoop thickness on the fire resistance of joints are mainly considered.