In steel trapezoidal box girder bridge systems, the U-shaped steel girder is designed to act compositely with the concrete deck to form a closed box for live loading. During the construction stage, however, the behavior is not well understood. The usual practice of assuming the system to be non-composite during construction requires substantial top flange bracing to form a quasi-closed box sect...

HEPS-TF is the test facility of HEPS (High Energy Photon Source) of China. The magnet girders are used for supporting and positioning of the magnets. As the beam emittance is very low, the girder must has high adjusting precision and high stability. Besides, the girder should also be beam-based aligned. For these issues, two girder systems are designed. Both of them use cam mover mechanisms for...

Based on the theory of vehicle track coupling dynamics, the local vibration of the high-speed railway box girder is analyzed by the Finite Element Method and the model is simulated with the solid elements. Through the study of vibration characteristics of the selected 6 sensitive points, the local vibrations in different parts of the box girder are figured out. It is compared the response of th...

The LCLS x-ray FEL has recently achieved its 1.5Angstrom lasing and saturation goals upon first trial. This was achieved as a result of a thorough pre-beam checkout, both traditional and beam-based component alignment techniques, and high electron beam brightness. The x-ray FEL process demands very tight tolerances on the straightness of the electron beam trajectory (<5 μm) through the LCLS und...

Cantilevers are a part of our life, they everywhere: bridg–es, building’s balconies, traffic signs, car parking shades even the aircraft’s wings. The long cantilevers buildings always present as big challenge to structural engineers in their practice life. behavior these depends on several factors, such rigidity slab, columns or walls, span continuity... etc. But real dilemma lies economical ch...

composite steel concrete composite floor used mainly in the commercial and office building has lighter weight and is considered very economical. the light weight natures of this type of floor causes some vibration problems when it is subjected to loadings such as human footstep loading. the dynamic characteristics of these floors are dependent on several parameters such as joist span, girder sp...

Abstract: Based on the characteristics of box girder with corrugated steel webs, the existing prestressing force, the effect of shear deformation of composite girder on the deflection, “folding effect” in longitudinal direction of corrugate steel webs and the arrangement of external tendons were considered comprehensively. With the experiment results of five literatures integrated, N/fcA (the a...

In this study, the free vibration analysis of smart vibration control (SVC) systems based on Reddy – Levinson model and modified strain gradient theory is developed. This system consist of a micro beam at middle and two magneto-electro-elastic (MEE) composite micro beams at top and bottom which connected by enclosing elastic medium and simulated by Winkler and Pasternak foundation. The effects ...

This study investigates the seismic behavior of deconstructable composite steel/concrete floor systems consisting of precast concrete planks and deconstructable clamping connections attaching the planks to the steel floor beams. The system is proposed to promote sustainable design of composite steel/concrete floor systems in steel buildings via reuse of the structural steel and concrete compone...