000013149 001__ 13149
000013149 005__ 20161114160329.0
000013149 04107 $$aeng
000013149 046__ $$k2009-06-22
000013149 100__ $$aCole G., L.
000013149 24500 $$aThe effect of diaphragm wave propagation on the analysis of pounding structures

000013149 24630 $$n2.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000013149 260__ $$bNational Technical University of Athens, 2009
000013149 506__ $$arestricted
000013149 520__ $$2eng$$aBuilding pounding is frequently observed during earthquakes in regions of dense urban populations, with damage levels ranging from cosmetic to catastrophic for buildings with insufficient separation. While the numerical modeling of pounding has significantly progressed in recent years, significant uncertainty still remains in many collision properties. The collision force itself is highly dependent on the stiffness of the so called ‘collision element’, yet this stiffness is not well characterized in the existing literature. This paper identifies building pounding as the collision of two distributed masses and subsequently analyses the collision in terms of the one dimensional wave equation. Collision properties are derived from wave theory and numerically verified, building on the work of previous researchers [1]. An ‘instant wave’ method is proposed as a distributed mass equivalent to stereo mechanics. Numerical approximations of distributed masses are assessed in terms of displacement response. Two building configurations are subjected to 10 second excitations with 5 % modal damping. The collision element stiffness in lumped mass models is also investigated to determine the most accurate response. It is found that at least three nodal masses connected by axial spring elements should be used to represent each diaphragm in order to provide consistently accurate displacement results. The contact element stiffness should be calculated with γ = 1 and the element stiffness of the stiffer diaphragm should be used in this calculation.

000013149 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000013149 653__ $$aPounding, Wave Propagation, Distributed Mass, Collision Element, Building, Impact. Abstract. Building pounding is frequently observed during earthquakes in regions of dense urban populations, with damage levels ranging from cosmetic to catastrophic for buildings with insufficient separation. While the numerical modeling of pounding has significantly progressed in recent years, significant uncertainty still remains in many collision properties. The collision force itself is highly dependent on the stiffness of the so called ‘collision element’, yet this stiffness is not well characterized in the existing literature. This paper identifies building pounding as the collision of two distributed masses and subsequently analyses the collision in terms of the one dimensional wave equation. Collision properties are derived from wave theory and numerically verified, building on the work of previous researchers [1]. An ‘instant wave’ method is proposed as a distributed mass equivalent to stereo mechanics. Numerical approximations of distributed masses are assessed in terms of displacement response. Two building configurations are subjected to 10 second excitations with 5 % modal damping. The collision element stiffness in lumped mass models is also investigated to determine the most accurate response. It is found that at least three nodal masses connected by axial spring elements should be used to represent each diaphragm in order to provide consistently accurate displacement results. The contact element stiffness should be calculated with γ = 1 and the element stiffness of the stiffer diaphragm should be used in this calculation.

000013149 7112_ $$aCOMPDYN 2009 - 2nd International Thematic Conference$$cIsland of Rhodes (GR)$$d2009-06-22 / 2009-06-24$$gCOMPDYN2009
000013149 720__ $$aCole G., L.$$iDhakal R., P.$$iCarr A., J.$$iBull D., K.
000013149 8560_ $$ffischerc@itam.cas.cz
000013149 8564_ $$s858109$$uhttps://invenio.itam.cas.cz/record/13149/files/CD200.pdf$$yOriginal version of the author's contribution as presented on CD, section: Seismic safety assessment of structures - ii (MS).
000013149 962__ $$r13074
000013149 980__ $$aPAPER