Search results for "Joints"

Seismic Performance of Earthquake-Resilient RC Frames Made with HSTC Beams and Friction Damper Devices

2021

Seismic behavior of RC frames with hybrid steel-trussed concrete beams is affected by panel zone damage due to a large amount of longitudinal reinforcement. Here the seismic efficiency of innovative frames characterized by friction damper devices (FDDs) at beam-to-column connections is compared against traditional frame. Three configurations are investigated: FDDs alone; FDDs with column-to-foundation connections having preloaded threaded bars and disk springs; FDDs with self-centering friction devices. Non-linear analyses show that FDDs alone prevent plastic hinge formation at beam ends and beam–column joint damage. FDDs with self-centering friction devices effectively limit both peak and …

On the mechanical behavior of BFRP to aluminum AA6086 mixed joints

2013

The aim of this work is to analyze the possibility to join aluminum alloy AA6086 and composite laminates reinforced with basalt fibers, an innovative material which use is growing in several applications as an alternative to glass fibers. To this goal, three joining techniques were investigated: mechanical by Self Piercing Riveting (in the next called SPR), adhesive by co-curing technique and mixed in which the joining techniques (i.e. adhesive and mechanical) were combined. Two manufacturing technologies (i.e. hand lay-up and vacuum bagging) were used both to produce composite substrates and to realize co-curing adhesion between the substrates to be joined. Mixed joints were realized by in…

On the moving loads problem in discontinuous homogeneous beams and layered beams with interlayer slip

This manuscript contains the main part of my research performed in this last triennium at the Department of Civil, Environmental, Aerospace and Materials Engineering, University of Palermo, and at the Department of Basic Sciences in Engineering Sciences (Unit of Applied Mechanics), University of Innsbruck, Austria. The research adheres to a common procedure of solving a scientistic problem. That is, introduction to the problem, selection of the mathematical and physical tools to model the problem, proposed solution, and numerical validation. The thesis proposes a novel modal superposition approach to the moving loads problem on discontinuous homogeneous beam and layered beam with interlayer…

Morphology of the dorsal and lateral calcaneocuboid ligaments.

2008

Background: The dorsolateral calcaneocuboid ligaments have different configurations. In the literature they are only described as either the dorsal or lateral calcaneocuboid ligament. However, recent reconstructive surgical techniques may benefit from a better understanding of the anatomy. The aims of this study were to classify the morphology and attachments of the dorso-lateral calcaneocuboid ligaments and to determine their dimensions. Materials and Methods: The dorso-lateral aspects of the calcaneocuboid joint of 30 cadaver feet were dissected to expose the associated ligaments. Further, we evaluated possible bony landmarks of the calcaneus that could imply which shape or course the li…

Topology Management in wireless sensor networks

2020

Wireless sensor networking is ingratiating itself into almost every area of human endeavors. Its drivers include its usages, improvements in microelectronics and manufacturing techniques. The network is made up of multiple tiny sensor nodes deployed in the area to be sensed, with nodes having processing, communicating, and sensing capabilities that enable them to perform their function collaboratively. Nodes sense events and transmit their data to the sink directly or through intermediate nodes acting as relay.Despite all the tremendous advances that have been made on this technology over the past few years, energy has not kept pace. This is based mostly on the fact that battery is its main…

Experimental test results vs. analytical prediction of welded joint strength in hybrid steel trussed concrete beams (HSTCBs)

2013

The aim of the paper is to provide practical guidelines for the design of welded joints of steel truss for encased composite steel–concrete beams. The results of experimental tests are presented and interpreted. The steel truss is made of a steel plate acting as the bottom chord, made of S355 structural steel, coupled with steel rebars which form the upper chord, and steel inclined web rebars (V-reverse) welded to the two chord elements, both of them made of steel B450C. Butt welded joints of web bar to bottom steel plate and fillet welding joints of inclined web bars to top chord bars were tested, as they are different from the ones which are normally used due to the coupling of different …

Validation of a subject specific 3-actuator torque-driven model in human vertical jumping.

2013

In this study, a forward dynamic subject specific 3-actuator torque-driven model of the human musculoskeletal system was created based on measurements of individual characteristics of a subject. Simulation results were compared with experimental vertical squat jumping with and without adding weights. By analyzing kinematic and kinetic experimental data at the instant of the toe-off for the same initial conditions, it was shown that a simple computer simulation using a suitable cost function could reproduce the real task performed by humans. This investigation is the first step in a wider project that will incorporate elastic components, and that will evaluate the advantages of the individua…

Re-analysis of fatigue data for welded joints using the notch stress approach

2010

Abstract Experimental fatigue data for welded joints have been collected and subjected to re-analysis using the notch stress approach according to IIW recommendations. This leads to an overview regarding the reliability of the approach, based on a large number of results (767 specimens). Evidently, there are some limitations in the approach regarding mild notch joints, such as butt joints, which can be assessed non-conservatively. In order to alleviate this problem, an increased minimum notch factor of Kw ⩾ 2.0 is suggested instead of the current recommendation of Kw ⩾ 1.6. The data for most fillet-welded joints agree quite well with the FAT 225 curve; however a reduction to FAT 200 is sugg…

A New Friction Stir Welding Based Technique for Corner Fillet Joints: Experimental and Numerical Study

2010

Friction stir welding (FSW) is an energy efficient and environmentally "friendly" (no fumes, noise, or sparks) welding process, during which the sheets are welded together in a solid-state joining process. FSW is mature for simple configurations but a significant lack of knowledge is found when dealing with different designs such as T-sections, corner welds and box sections. The present work explores the feasibility of producing corner fillet geometries using FSW. Although such a kind of geometry has traditionally been considered unfeasible for the process, it seems to have a great potential to be used for T-joint configurations, a recurrent design pattern in transport applications. A speci…

On the material flow in fsw of T-joints: influence of geometrical and tecnological parameters

2008

Friction stir welding (FSW) now definitively reached a large interest in the scientific community and what is more in the industrial environment, due to the advantages of such solid state welding process with respect to the classic ones. The latter aspects are relevant also with reference to joints characterized by a complex geometry. What is more, advanced FEM tools permit to develop effective engineering of the processes; quantitative results can be acquired from numerical simulations once basic information, as the process mechanics and the material flow, are certain. Material flow plays a fundamental role in FSW since it determines the effectiveness of the joints or, in turn, the insurge…