Yasunori Arizumi

Finite strip analysis of curved composite girders with incomplete interaction

This paper presents a finite strip analysis of curved composite girders with incomplete interaction. In the present analysis curved composite girder bridges are modelled by curved strip elements for the concrete slab and steel girder and spring elements for the shear connectors. The shear connectors are assumed as a two-dimensional spring element along the nodal line. The proposed method is applied to the analysis of curved box girders, curved plates and curved composite girder bridges with complete and incomplete interaction. Some analytical results obtained by this method are compared with the test results and theoretical values obtained by other methods, and they are in good agreement. Slip behavior of curved composite box girders is also discussed based on the results by the proposed method.

Instability of Axially Loaded Compression Members under Lateral Rigid Body Excitations

The global compressive capacity of steel members subject to lateral rigid body dynamic excitation is examined numerically with a dynamic nonlinear finite-element analytical algorithm that uses the implicit Newmark-β integration procedure combined with the Newton-Raphson iterative scheme. The algorithm was validated with experimental results. Parametric studies on 180 box, tube, and W shapes are presented. The members included initial geometric imperfections along their lengths. On the basis of the parametric study, a simplified formula for the buckling capacity of a steel member under lateral rigid body excitations is presented that may be considered for the use in the development of a design formula.

A PRACTICAL ESTIMATION OF DYNAMIC PHYSICAL PROPERTIES OF SUBSURFACE LAYERS IN OKINAWA PREFECTURE

ある特定地域における地震災害防災を検討する場合に, サイスミックゾネーションマップが重要な資料となる. しかし, 沖縄県のような島嶼地域特有の小地形を考慮する必要がある場合には, 従来利用されてきたマップメッシュの妥当性及び細分化の検討が必要となる. その細分化によるマップメッシュの増大に伴い, 必要とされる地盤情報も増大する. したがって, 地盤情報に関する資料不足が問題となることが想定される. そこで, 本研究では, 地形分類図および過去の地盤情報について統計処理した結果を利用することで, これらの資料不足に対する補完手法を提案するものである.