Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Reliability Analysis Of Shallow Foundations Bearing Capacity On Sand, Ali Alhajami Jul 2013

Reliability Analysis Of Shallow Foundations Bearing Capacity On Sand, Ali Alhajami

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Bearing capacity of shallow foundation is one of the most challenging problems for engineers. The difficulty comes from multiple sources of variability and uncertainty. There is an uncertainty in live load. Soil properties including: unit weight, cohesion, and angle of friction represent sources of variability in the determining bearing capacity. The current theories used in practice only estimate bearing capacity and does not give an exact value for it because of these sources of variability. Currently, there are Terzaghi, Meyerhof, Vesic, and Hansen theories for dealing with this problem. Based on previous research Terzaghi theory was found to be the …


Active Tuned Mass Damper Control Of Wind Turbine Nacelle/Tower Vibrations With Damaged Foundations, Breiffni Fitzgerald Jan 2013

Active Tuned Mass Damper Control Of Wind Turbine Nacelle/Tower Vibrations With Damaged Foundations, Breiffni Fitzgerald

Breiffni Fitzgerald

The aim of this paper is to develop an active structural control scheme to control wind turbine nacelle/tower out-of-plane vibration. An active tuned mass damper (ATMD) is designed an placed inside the turbine nacelle. An EulerLagrangian wind turbine model based on energy formulation is developed for this purpose, which considers the structural dynamics of the system and the interaction between in-plane and out-of-plane vibrations. Also, the interaction between the blades and the tower including the ATMD is considered. The wind turbine is subjected to gravity and turbulent aerodynamic loadings. A three-dimensional (3D) model of a wind turbine foundation is designed …