It is common to use sound insulation as a last resort for noise control in an urban city. Sound insulation of air-conditioned building is of importance. The stiffeners have important effects on the sound insulation properties of a stiffened structure. The experimental studies on the stiffened structures are vital for the study of the stiffener effects. Based on this concern, a simple stiffened ...

Presently, wrapping of the welds at the ends of stiffeners is not done to avoid the undercutting of the stiffener corners and the attendant weld repair. The fatigue performance of stiffeners with undercuts was evaluated in a factorial design fatigue experiment. Undercuts at the flange edge and filling of the stiffener cope with the fillet weld were also evaluated. The undercuts did not influenc...

Thin-shell deployable reflector structures that are folded elastically in a nearly-inextensional mode have been recently realized, exploiting the recent availability of high-modulus, ultra-thin composite materials. An inherent, and significant limitation of this approach is that these structures remain “floppy” in their deployed configuration. This paper presents a general concept for increasin...

Background and Objectives. A key factor for the long-term function of a dental implant is the manner in which stresses are transferred to the surrounding bone. The effect of adding a stiffener to the tissue side of the Hader bar helps to reduce the transmission of the stresses to the alveolar bone. But the ideal thickness of the stiffener to be attached to the bar is a subject of much debate. T...

We have recently proposed a new concept for deployable reflectors consisting of a thin parabolic carbon-fibre-reinforced-plastic (CFRP) shell stiffened along the edge by an elastically collapsible stiffener. Here we show that a stiffener accounting for less than 10% of the total mass of the reflector increases the stiffness of the softest deformation mode of the deployed reflector by 48 times, ...

The paper presents the development of a new plate/shell stiffener element and the subsequent application in determine frequencies, mode shapes and buckling loads of different stiffened panels. In structural modelling, the plate and the stiffener are treated as separate finite elements where the displacement compatibility transformation takes into account the torsion – flexural coupling in the s...

A vibration based damage identification algorithm is implemented to assess the damage of a thin–walled composite structure. The structure analysed is a skin with stiffeners, as frequently applied in aircraft components. Both experimental and numerical studies on a single composite skin–stiffener structure showed that the modal strain energy damage index (MSE–DI) algorithm is a suitable method f...

Thin-shell deployable reflector structures that are folded elastically in a nearly inextensional mode have been recently realized, exploiting the recent availability of high-modulus, ultrathin composite materials. An inherent and significant limitation of this approach is that these structures remain “floppy” in their deployed configuration. This paper presents a general concept for increasing ...

This paper proposes a continuous leakage location method based on the ultrasonic array sensor, which is specific to continuous gas leakage in a pressure container with an integral stiffener. This method collects the ultrasonic signals generated from the leakage hole through the piezoelectric ultrasonic sensor array, and analyzes the space-time correlation of every collected signal in the array....

The stiffened rectangular plate was usually adopted in the blast airtight doors. In order to improve the buckling capacity of stiffened rectangular plate under uniform normal compression, the optimization model of stiffened rectangular plate was set up based on APDL and ANSYS commands, and the sequential linear programming method was executed to optimize the thickness of plate and the sizes of ...