Keywords : Static seismic load, Single layer lattice dome, Continuum shell analogy, Elasto-plastic buckling analysis, Buckling load factor, Incremental dynamic analysis 静的地震荷重，単層ラチスドーム，連続体置換，弾塑性座屈解析，座屈荷重係数，動的増分解析Although large numbers of attempts have been made to evaluate buckling strength of single layer lattice domes under equallydistributed vertical loads, stability under seismic loads has not been studied enough yet. In this paper, evaluation method on buckling strength of single layer lattice domes based on continuum shell analogy under equivalent static seismic loads proposed in the previous studies is investigated. First, the buckling behavior under distributed loads proportional to the static seismic loads is researched taking shape parameters into account. Next, the buckling strength for vertical loads and the buckling strength for static seismic loads is evaluated using continuum shell analogy, and converted to elasto-plastic buckling strength using knockdown factors and Dunkerley formulation. The effectiveness of the proposed evaluation is discussed against the results of time-history response analyses. FV' 15) FV /FH 14)FV'/FH'FH' (1) (2), ,

Although large numbers of attempts have been made to evaluate buckling strength of cylindrical lattice shell roofs under equally-distributed vertical loads, stability under seismic loads has not been studied enough yet. In this paper, evaluation method on buckling strength of cylindrical lattice shell roofs based on continuum shell analogy under equivalent static seismic loads proposed in the previous studies is investigated. First, the buckling behavior under distributed loads proportional to the static seismic loads is researched taking shape parameters into account. Next, the buckling strength for vertical loads and the buckling strength for static seismic loads is evaluated using continuum shell analogy, and converted to elasto-plastic buckling strength using knockdown factors and Dunkerley formulation. The effectiveness of the proposed evaluation is discussed against the results of time-history response analyses.

The present paper discusses the semi-active vibration control of double-layer cylindrical lattice shells with variable damping mechanisms. Some attempts to install the passive or active control devices to the lattice shell roofs are proposed for the purpose of controlling the seismic response of shell and spatial structures. Nowadays reserches of semi-active control is developed that produces any adjustable control forces by using variable damping mechanisms. However, there are few applications of this control method to the spatial strucutures. First, we attempt to apply the semi-active control method to a double-layer cylindrical lattice shell to reduce the seismic response. Second, the control effects are analysed and the results obtained by time history analysis are compared with of the passive and active control. Moreover, an arrangement method of variable dampers that considers the unique vibration characteristics of the lattice shells is proposed.

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