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The purpose of this paper is to establish a maturity evaluation model for the application of construction steel structure welding robotics suitable for the actual situation and specific characteristics of engineering projects in China and then to assess the maturity level of the technology in the application of domestic engineering projects more scientifically.

The research follows a qualitative and quantitative analysis method. In the first stage, the structure of the maturity model is constructed and the evaluation index system is designed by using the ideas of the capability maturity model and WSR methodology for reference. In the second stage, the design of the evaluation process and the selection of evaluation methods (analytic hierarchy process method, multi-level gray comprehensive evaluation method). In the third stage, the data are collected and organized (preparation of questionnaires, distribution of questionnaires, questionnaire collection). In the fourth stage, the established maturity evaluation model is used to analyze the data.

The evaluation model established by using multi-level gray theory can effectively transform various complex indicators into an intuitive maturity level or score status. The conclusion shows that the application maturity of building steel structure welding robot technology in this project is at the development level as a whole. The maturity levels of “WuLi – ShiLi – RenLi” are respectively: development level, development level, between starting level and development level. Comparison of maturity evaluation values of five important factors (from high to low): environmental factors, technical factors, management factors, benefit factors, personnel and group factors.

In this paper, based on the existing research related to construction steel structure welding robot technology, a quantitative and holistic evaluation of the application of construction steel structure welding robot technology in domestic engineering projects is conducted for the first time from a project perspective by designing a maturity evaluation index system and establishing a maturity evaluation model. This research will help the project team to evaluate the application level (maturity) of the welding robot in the actual project, identify the shortcomings and defects of the application of this technology, then improve the weak links pertinently, and finally realize the gradual improvement of the overall application level of welding robot technology for building steel structure.

IN ANY survey of stainless steel applications it is soon apparent that in the vast majority of cases it is the corrosion resistance of the material which is the deciding factor in its selection. Appearance, non‐toxicity, retention of strength at high and low temperatures, and ease of fabrication are all important in varying degrees, but the widespread applications of stainless steel— a material which celebrated its first half‐century only a few years ago—follow principally from its inherent ‘stainless’ properties which confer a remarkable degree of resistance to attack in a wide variety of environments.

The purpose of this study was to determine correlation between an accelerated cyclic corrosion test (S6‐cycle test) specified in Japanese Industrial Standards K5621 and field exposure tests, and to open up applications of the accelerated tests in various regional environments.

The S6‐cycle corrosion test was carried out on structural steels for 30, 60, 90, 120 and 150 days and metal coating films for 100, 200 and 300 days. Comparing the weight loss of the steels with 1‐, 3‐, 5‐ and 9‐year field exposure test data at 31 sites in Japan. Correlation of the S6‐cycle tests to the field exposure tests was determined by acceleration coefficients.

The correlation between the S6‐cycle test and the field test on uncoated structural steels can be determined by acceleration coefficients based on flying salt amount. The coefficients were applicable for durability prediction of uncoated, zinc hot‐dip galvanized and painted steels.

In determination of the accelerated coefficients, only the flying salt amount was considered. Others factors such as temperature and humidity will be considered in future work.

Using the S6‐cycle corrosion test and its accelerated coefficients, the thickness loss of uncoated structural steels and zinc hot‐dip galvanizing is predictable in a short time. Corrosion degradation of coated steels is also predictable approximately.

This paper contributes to open up the application of accelerated cyclic corrosion test to evaluating corrosion resistance of steel bridge members.

In this research work thick‐film manufacturing technology on stainless steel baseplates was developed. Adequate adhesion of dielectric IP211 to the steel substrate was achieved only by sand blast roughening. Standard PdAg thick‐film conductors were not solderable to IP211. The solution was to have a separate multilayer dielectric under conductors to be soldered. The reliability of soft soldering and gold wire bonding of thick‐film metallisation on stainless steel and other baseplate materials was evaluated. The technology developed was applied to manufacturing an intelligent signal node. Present expertise enables the manufacture of thick‐film hybrids on stainless steel baseplates. Development of an industrial production line would, however, involve considerable effort.

The steel construction market has undergone gradual development in the past decades given its profound impacts on environment, economy and society. The purpose of this paper is to facilitate a better understanding of the major drivers and issues behind the market development of the steel construction industries around the world.

A three-step desktop research was conducted to select relevant research outputs published in the past 20 years. The research methodology in conducting these studies and their research trends were analyzed. Then the potential influencing factors for the market development of steel construction were identified through a content analysis of the selected studies.

A total of 59 articles were identified accordingly. These influencing factors were divided into five main themes: contextual, institutional, industrial, project-related and individual factors. In terms of the frequencies of these factors appeared in previous studies, “continuous development of standards, codes, and specifications” and “advance in product and process technology” were the top two driving forces in the market development of steel construction, while “cost issues” was the most frequently reported obstacle.

The study takes an initiative to establish a practical classification framework that can be dedicated to illuminating the critical issues or success factors affecting the development of the steel construction market. This framework can help policymakers, industry practitioners and researchers achieve sustaining success in steel construction in the developed, emerging and inactive markets.

Stainless steel has different advantages when compared to conventional carbon steel. The corrosion resistance and aesthetic appearance are the most known; however, its better behaviour under elevated temperatures can also be important in buildings design. In spite of the initial cost, stainless-steel application as a structural material has been increasing. Elliptical hollow sections integrate the architectural attributes of the circular hollow sections and the structural advantages of the rectangular hollow sections (RHSs). Hence, the application of stainless-steel material combined with elliptical hollow profiles stands as an interesting design option. The purpose of the paper is to better understand the resistance of stainless-steel-beam columns in case of fire

The research presents a numerical study on the behaviour of stainless-steel members with slender elliptical hollow section (EHS) subjected to axial compression and bending about the strong axis at elevated temperatures. A parametric numerical study is presented here considering with and without out-of-plane buckling different stainless-steel grades, cross-section and member slenderness, bending moment diagrams and elevated temperatures.

The tested design methodologies proved to be inadequate for the EHS members being in some situations too conservative.

The safety and accuracy of Eurocode 3 (EC3) design methodology and of a recent design proposal developed for I-sections and cold-formed RHSs are analysed applying material and geometric non-linear analysis considering imperfections with the finite element software SAFIR.

The purpose of this paper is to investigate the performance of intumescent coating on tension rod systems and their components. Steel tension rod systems consist of tension rods, fork end connectors and associated intersection or gusset plates. In case of fire, beside the tension rods themselves, the connection parts require appropriate fire protection. Intumescent fire protection coatings prevent a rapid heating of the steel and help secure the structural load-carrying capacity. Because the connection components of tension rod systems feature surface curvature and a complex geometry, high demand is placed on the intumescence and thermal protection performance of the coatings.

In this paper, experimental studies were carried out for steel tension rod systems with intumescent coating. The examined aspects include the foaming and cracking behaviour, the influence of different dry film thicknesses, the heating rate of the steel connecting parts in comparison to the tension rods, and the mounting orientation of the tension rods together with their fork end connectors.

The results show that a decrease in surface curvature and/or an increase in mass concentration of the steel components leads to a lower heating rate of the steel. Moreover, the performance of the intumescent coating on tension rod systems is influenced by the mounting orientation of the steel components.

The findings based on fire tests contribute to a better understanding of the intumescent coating performance on connection components of tension rod systems. This subject has not been extensively studied yet.

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.

Duplex stainless steels have become important competitors to austenitic stainless steels in many applications and a great deal of attention has focused on the welding aspects. The introduction of modern grades with improved properties and a competitive price level have increased their use in the offshore, petrochemical and shipbuilding industries, for example. In particular the newer grades, with their higher nitrogen content and improved weldability, have moved duplex stainless steels from a position as “interesting” materials to one of “useful in practice”. However, duplex stainless steels differ from austenitic grades in some respects, and know‐how combined with the use of appropriate welding procedures and consumables is therefore the key to successful welding.

Concrete-filled steel hollow (CFHS) column is an innovation to improve the performance of concrete or steel column. It is believed to have high compressive strength, good plasticity and is excellent for seismic and fire performance as compared to hollow steel column without a filler.

Experimental and numerical investigation has been carried out to study the performance of CFHS having different concrete in-fill and shape of steel tube.

In this paper, an extensive review of experiment performed on CFHS columns at elevated temperature is presented in different types of concrete as filling material. There are three different types of concrete filling used by the researchers, such as normal concrete (NC), reinforced concrete and pozzolanic-fly ash concrete (FC). A number of studies have conducted experimental investigation on the performance of NC casted using recycled aggregate at elevated temperature. The research gap and the recommendations are also proposed. This review will provide basic information on an innovation on steel column by application of in-filled materials.

Design guideline is not considered in this paper.

Fire resistance is an important issue in the structural fire design. This can be a guideline to define the performance of the CFHS with different type of concrete filler at various exposures.

Utilization of waste fly ash reduces usage of conventional cement (ordinary Portland cement) in concrete production and enhances its performance at elevated temperature. The new innovation in CFHS columns with FC can reduce the cost of concrete production and at the same time mitigate the environmental issue caused by waste material by minimizing the disposal area.

Review on the different types of concrete filler in the CFHS column. The research gap and the recommendations are also proposed.