Takashi Ueki

Study of Dynamic Collapse of Single Layer Reticular Domes Subjected to Earthquake Motion and the Estimation of Statically Equivalent Seismic Forces

The present paper investigates the dynamic response characteristics of single layer reticular domes subjected to horizontal earthquake motions from the following view points: (1) how to estimate the statically equivalent seismic forces applied to domes both for high rise and low rise; and (2) how to estimate the collapse accelerations under which the domes collapse dynamically. For these purposes, linear response analyses, linear buckling analyses, geometrically and materially nonlinear static analyses and geometrically and materially nonlinear earthquake response analyses are performed. Based on the results, the collapse accelerations are expressed as a function of the safety factor for domes under self weight. The expression for the collapse accelerations leads to an approximate measure by which structural designers may balance the static resistant capacity under self weight and the dynamic resistant capacity under earthquake motions.

Buckling Load of Elliptic Paraboloidal Single Layer Reticulated Roofs under Uniform Load

The present paper discusses buckling strength of elliptic paraboloidal reticular roofs under a uniform load on a rectangular plan. The roofs are assumed as three way single layers with a pin-support at all peripheries on a rectangular plan. The buckling analyses are performed for linear buckling, elastic buckling and elastic-plastic buckling. The results of buckling loads are formulated based on two procedures for practical design use. One is an explicit but approximate formula for elastic buckling loads using a knock down factor and the other one is an implicit expression for buckling loads interpreted into a column buckling strength in terms of generalized slenderness ratio.

Buckling Load of Elliptic Paraboloidal Single Layer Reticulated Roofs with Simple Supports under Uniform Load

The present paper discusses buckling strength of elliptic paraboloidal reticular roofs under uniform load with a rectangular plan. The roofs are assumed as three way single layers with a simple support at all peripheries of a rectangular plan. The buckling analyses are performed for linear buckling, elastic buckling, and elastic-plastic buckling. The results of buckling loads are formulated based on two procedures for practical design use. One is an explicit formula for elastic buckling loads using a knock down factor and the other one is an implicit expression for buckling loads interpreted as a column buckling strength in terms of generalized slenderness ratio.

Estimation of Buckling Loads of Elliptic Paraboloidal Single Layer Lattice Domes under Vertical Loads

The present paper presents an effective evaluation method for elasto-plastic buckling loads of elliptic paraboloidal lattice domes for roof on a rectangular plan. The roofs are assumed as three way of single layer with a pin-support or a simple-support at all peripheries on a rectangular plan. The buckling loads are evaluated using a simple procedure adopting a linear buckling analysis, a knockdown factor for imperfection sensitivity, and column buckling strength for axial forces in terms of a generalized slenderness proposed in ordinary recommendations.