Buy article PDF
The purchased file will be sent to you
via email after the payment is completed.
US$ 35
|
Structural Engineering and Mechanics Volume 42, Number 2, April25 2012 , pages 191-210 DOI: https://doi.org/10.12989/sem.2012.42.2.191 |
|
|
|
An Extended Force Density Method for the form finding of cable systems with new forms |
||
P.G. Malerba, M. Patelli and M. Quagliaroli
|
||
| Abstract | ||
| The Force Density Method (FDM) is a well known and extremely versatile tool in form finding of cable nets. In its linear formulation such method makes it possible to find all the possible equilibrium configurations of a net of cables having a certain given connectivity and given boundary conditions on the nodes. Each singular configuration corresponds to an assumed force density distribution. Its improvement as Non-Linear Force Density Method (NLFDM) introduces the possibility of imposing assigned relative distances among the nodes, the tensile level in the elements and/or their initial undeformed length. In this paper an Extended Force Density Method (EFDM) is proposed, which makes it possible to set conditions in terms of given fixed nodal reactions or, in other words, to fix the positions of a certain number of nodes and, at the same time, to impose the intensity of the reaction force. Through such extension, the (EFDM) enables us to deal with form findings problems of cable nets subjected to given constraints and, in particular, with mixed structures, made of cables and struts. The efficiency and the robustness of method are assessed through comparisons with other form finding techniques in dealing with characteristic applications to the prestress design of cable systems. As a further extension, the EFDM is applied to structures having some parts not yet geometrically defined, as can happen in designing new creative forms. | ||
| Key Words | ||
| cable structures; form finding; force finding; force density method; new structural forms | ||
| Address | ||
| P.G. Malerba: Department of Structural Engineering, Politecnico di Milano, 20133 Milan, Italy M. Patelli: Studio Malerba, 20133 Milan, Italy M. Quagliaroli: Department of Structural Engineering, Politecnico di Milano, 20133 Milan, Italy | ||