The National Institute of Standards and Technology (NIST) Construction Metrology and Automation Group, in cooperation with the NIST Intelligent Systems Division, is researching robotic structural steel placement through an ongoing program entitled ‘‘Performance of Innovative Technologies for Automated Steel Construction.’’ This program, initiated in response to an American Institute of Steel Co...

Cast steel nodes are being increasingly popular in steel structure joint application as their advanced mechanical performances and flexible forms. This kind of joints improves the structural antifatigue capability observably and is expected to be widely used in the structures with fatigue loadings. Cast steel node joint consists of two parts: casting itself and the welds between the node and th...

The use of fly ash is not only in harmony with the concept of sustainable development, but also beneficial to some mechanical properties of concrete. This paper discusses steel corrosion rate time-changing law in concrete with different replacing ratios of low calcium fly ash(10%~30%) and the microcosmic characteristic of concrete-steel interface. The steel corrosion rate was tested by linear p...

The dependency of uniform corrosion of structural steel on the average grain size (D) should be quantified for design purposes. In the present work, a spectrum of grain sizes was obtained by simple heat treatment routes in st37 structural steel. It was revealed that the corrosion current density (icorr) increased by grain refinement, which was related to the increased density of grain boundarie...

This paper attempts to improve the computational efficiency of the well known particle swarm optimization (PSO) algorithm for tackling discrete sizing optimization problems of steel frame structures. It is generally known that, in structural design optimization applications, PSO entails enormously time-consuming structural analyses to locate an optimum solution. Hence, in the present study it i...

This study presents the optimal drift design method to control the elastic and inelastic performance of steel moment frames. This is formulated as a problem that minimizes the lateral displacement at the top of a building satisfying the constraints on the total structural weight and the column-to-beam strength ratios at the joints. This uses the resizing method based on the linear static analys...

Calculations were performed to quantify the damage parameters in the leading candidate structural and plasma facing materials when used in magnetic and inertial confinement fusion systems and when irradiated in fission reactors. The structural materials considered are ferritic steel, austenitic steel, vanadium alloy and SiC/SiC composite. Plasma facing materials included beryllium, tungsten, an...

The study of mechanical behavior of the structural steel S400 under quasi- static and dynamic loading has been the subject of this investigation. In oder to obtain different stress - triaxiality conditions the specimens were notched with 1, 1.5, 2 and 3.5 mm notch radius. The results of fractography show as the velocity of tension increases, ductility reduces and a ductile-brittle transition oc...

The twin-roll strip casting process is a typical steel-strip production method which combines continuous casting and hot rolling process. The production line from molten liquid steel to the final steel-strip is shortened and the production cost is reduced significantly compared to the conventional continuous casting. The twin-roll strip casting process can produce 1-5 mm thin steel strip direct...

Steel containing 0.03% carbon, 1.35% copper and 0.84% nickel had yield strength in the 540-625 MPa (78-90 Ksi) range depending on thickness, ultimate tensile strength in the 625-690 MPa (90100 Ksi) range, and 25-30% elongation when air cooled after hot rolling. No brittle heat-affected zone was formed during manual or automatic submerged arc welding without pre-heating or postheating. The fract...