Performance Of Steel Structures Research Articles

Prediction of mechanical properties of light gauge steels at elevated temperatures

The deterioration of the mechanical properties of yield strength and modulus of elasticity is considered as the primary element affecting the performance of steel structures under fire. However, the variation of mechanical properties for light gauge and high strength steels at elevated temperatures is not known. Steels with thicknesses less than 1 mm and yield strengths greater than 500 MPa are commonly used in Australia. Therefore, an extensive experimental study into the deterioration of mechanical properties for both low and high strength light gauge steels under elevated temperatures was conducted to derive accurate reduction factors for mechanical properties in fire safety design. This study included light gauge cold-formed steels with three steel grades and six thicknesses from 0.4 to 1.2 mm. This paper presents the details of the experimental study, the results, the empirical equations for the reduction factors and a stress–strain model at elevated temperatures.

A New Structural Analysis Method to Assess the Long-Term Mechanical Performance of Steel Structures Considering Corrosion and Repair Yoshiaki GOTO and Naoki KAWANISHI

A New Structural Analysis Method to Assess the Long-Term Mechanical Performance of Steel Structures Considering Corrosion and Repair Yoshiaki GOTO and Naoki KAWANISHI

Advanced Analysis for Performance-based Design of Steel Structures Exposed to Fires

This paper presents an advanced plastic hinge analysis method that can be used to assess the performance of steel structures exposed to fire. The main feature of the analysis is to use as few elements as possible to model each structural member and to obtain a realistic representation of the global nonlinear effects of the structure. Natural fires are simulated using the proposed multizone and radiation models. The transient heat transfer is computed using a finite element method. Bounding surface theory is employed to allow for gradual plastification of steel cross sections. Performance-based assessments are carried out on a multistory car park structure and an arched frame exposed to localized car combustion. The effects of beam span, fire source location, and fire spread on the structural behaviors are investigated.

Seismic Design Guidelines and Provisions for Steel-Framed Buildings: FEMA 267/267A and 1997 AISC Seismic Provisions

One of the important surprises of the Northridge earthquake of January 17, 1994, was the widespread and unanticipated brittle fracture of welded steel beam-to-column connections. Although no casualties or collapses occurred during the Northridge earthquake as a result of these connection failures, and many WSMF buildings were not damaged at all, a wide spectrum of brittle connection damage did occur, ranging from minor cracking to completely severed columns. This paper summarizes two of the most important documents that have been developed in response to the damage suffered to steel moment frame buildings in the Northridge earthquake. The first, FEMA 267, Interim Guidelines: Evaluation, Repair, Modification and Design of Welded Steel Moment Frame Structures, was generated from studies undertaken as part of a project initiated by the U.S. Federal Emergency Management Agency (FEMA) to reduce the earthquake hazards posed by steel moment-resisting frame buildings. The second document addressed in this paper is the 1997 edition of the American Institute of Steel Construction (AISC) Seismic Provisions for Structural Steel Buildings (commonly referred to as the AISC Seismic Provisions) that incorporates the new information generated by the FEMA-sponsored project and other investigations on the seismic performance of steel structures, and has been adopted by reference into the 2000 International Building Code (IBC).

Ductility and Hysteresis Model of Steel Column Members.

To design steel structures more efficiently, it is necessary to appropriately evaluate the earthquake resistance performance of steel structures. In this study, we conducted cyclic loading tests of steel column members and steel frame pier models. Based on the test results, we investigated a quantitative evaluation method of steel members load carrying capacity and ductility and their hysteresis property. In addition, we investigated a method for evaluating earthquake resistance performance of steel rigid frame piers by using a simple analytical model.

Advanced analysis for the assessment of steel frames in fire

This paper describes the methodology of an advanced analysis technique for studying the large-displacement inelastic behaviour of building frames subjected to localised fire. The main feature of the proposed analysis is its use of one element per member to model each structural component and thereby obtain a realistic representation of material and geometrical nonlinear behaviour of the overall framework. Both ISO fire and natural fires can be simulated by the analysis model. The transient heat transfer is calculated by using a refined finite element mesh, whereas the structural responses are calculated with a nonlinear finite element technique based on an elasto-plastic beam–column formulation. Numerical studies are carried out on portal frames and multi-storey frames exposed to natural fires. The computed results are compared and contrasted with those from the conventional approach based on ISO standard fire, so that the advantage of using advanced analysis for direct assessment of the performance of steel structures in fire can be highlighted. Effects of fire load and ventilation resulting in localised fires in building frames are studied. The design implication of fire spreading in the storey of a building in which cooling and heating are taking place simultaneously is discussed.

Earthquake design and performance of steel structures

The 1994 Northridge earthquake has shown that steel structures may experience local failure modes that have not been observed in earlier earthquakes. The attention of the public and the engineering community has been drawn particularly to frequently observed fractures at welded beam-to-column connections. The local failures have raised design and research issues that have become the focus of extensive professional and research efforts directed towards improvement of the performance of steel structures in future earthquakes.

Performance of steel structures during the 1994 Northridge earthquake : R. Tremblay, P. Timler, M. Bruneau & A. Filiatrault, Canadian Journal of Civil Engineering, 22(2), 1995, pp 338–360

Performance of steel structures during the 1994 Northridge earthquake : R. Tremblay, P. Timler, M. Bruneau & A. Filiatrault, Canadian Journal of Civil Engineering, 22(2), 1995, pp 338–360

Performance of steel structures during the 1994 Northridge earthquake

The performance of concentrically braced steel frames and moment resisting steel frames during the January 17, 1994, Northridge, California, earthquake is examined. Most of the observations made during the reconnaissance visits confirmed the current knowledge on the inelastic response of these structural systems. This permits the anticipation of proper seismic behavior for buildings designed according to the seismic provisions that have been recently introduced in the Canadian building code and standard for steel structures. In some cases, however, the observed damage raised concerns that should be addressed in future investigations or next editions of these codes. Preventing potentially hazardous nonstructural damage, avoiding premature nonductile failures anywhere along the lateral load paths, limiting structural and nonstructural damage due to brace buckling, and accounting for the vertical ground motion are among those issues. Key words: earthquake, seismic, steel, concentrically braced frames, moment resisting frames, weld.

Hysteretic behaviour of steel members: Analytical models and experimental tests

Abstract The seismic performance of steel structures is highly dependent on the hysteretic behaviour of their members. The assessment of this behaviour cen be done by means of experimental tests and the use of analytical models that take into account the main phenomena involved in a non-linear response. An overview of experimental methodologies for cyclic tests, including a more detailed investigation of the ECCS recommendations, is presented. Analytical models for the simulation of hysteretic behaviour and comparisons with some experimental results are shown. Finally, it is demonstrated how a cumulative damage model for failure assessment allows for the evaluation of q factors for structural design.

Performance of Steel Structures in the September 19 and 20, 1985 Mexico Earthquakes

A description of the various types of steel structures built in Mexico City includes comparisons of the older types of steel construction with more modern buildings. Performance of steel buildings in the September 1985 earthquake was related to the local geotechnical conditions including foundation behavior. The collapses of the Edificio 21 Atlas and Conjunto Pino Suarez buildings raise important earthquake resistant design and research issues.

The effects of seawater on the integrity of offshore structures

SynopsisThis paper reviews the knowledge of deterioration processes which occur when steel and concrete structures are situated in seawater. The basic corrosion mechanisms of steel, together with possible methods of protection, are outlined briefly. With regard to coatings and cathodic protection, recent developments to counteract the increasingly severe conditions encountered by oil-production platforms in the North Sea, are discussed. Concrete structures usually provide a naturally-inhibitive internal environment to confer protection from corrosion to encased steel reinforcements, but mention is made of the possibilities of such protection becoming ineffective during long service in severe offshore conditions.The basic features of corrosion fatigue are described in the light of recent research but some aspects, which are of great importance for the performance of steel structures, are shown to be not well documented or understood. Corrosion fatigue of concrete structures has not been studied extensively, a particularly neglected area being the elucidation of the fundamental mechanisms of deterioration.