Advances of thin shell finite elements and some applications—version I

A survey of finite element models for the analysis of moderately thick shells

A finite element formulation and Gaussian quadrature procedure, using both the direct complex matrix inversion and the modal superposition methods, are presented for studying the stationary random response of shell structures, such as a cooling tower. The random distributed loads are assumed as stationary in time but can be nonhomogeneous in space. A 48 d.o.f. quadrilateral shell element with bi‐cubic Hermitian polynomial interpolation functions as displacement shape functions is adopted. The shape functions are used to form the matrix of cross‐spectral densities of the generalized nodal forces for distributed loads. The shape functions are also used to interpolate the response quantities at an arbitrary pair of points located within two different elements. Cross‐spectral densities of displacement and stresses are first obtained for a simply supported cylindrical panel subjected to purely random load, using both the direct and modal superposition methods, which are in excellent agreement with an earlier a...

Finite Element Random Response Analysis of Cooling Tower

Intending to achieve optimum finite element modeling of column supported cooling towers for seismic response studies according to the distributions of dominating bending and membrane stresses and intending to model the vulnerable shell‐column region using discrete column elements and quadrilateral shell elements, a set of elements is adopted, modified or extended. The set includes: (1) A 16 d.o.f. column element; (2) a 48 d.o.f. doubly curved quadrilateral general shell element; (3) a 42 d.o.f. doubly curved general‐membrane transition element; (4) a 21 d.o.f. and 39 d.o.f. doubly curved triangular membrane filler elements; and (5) a 28 d.o.f. doubly curved quadrilateral membrane element. Examples are given to evaluate a single type, combined types, and the whole set of elements with results in good agreement with alternative solutions. These elements may be used for accurate and efficient free vibration analysis of column supported cooling towers. The modeling may be used in seismic response analysis of ...

Shell Elements for Cooling Tower Analysis

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Cooling Tower Structures

Dynamic analysis of column‐supported hyperboloidal shells

A finite element analysis of a tank supported on columns attached to the shell wall is conducted based on an analytical model of the system. The effectiveness of a radial stiffener on reducing the design forces is demonstrated and the mechanism of axial load transfer between the columns and the shell is investigated. Also the distribution of the important design forces away from the column center line is considered.

Column Supported Cylindrical-Conical Tanks

Direct dynamic analysis of shells of revolution using high-precision finite elements☆

The computation of stresses within a finite element displacement method analysis of a shell of revolution is considered. The common procedure of applying the kinematic and constitutive laws to the displacement functions is examined and justified for models where the displacements are represented by high-order polynomial expansions. Also, two alternative computational formats within this technique are explored. The influence of the column-supported base condition on a hyperboloidal shell of revolution is studied with respect to the stresses calculated from a response spectrum analysis. These studies emphasize the importance of accurately modelling the base region of a column-supported shell such as a hyperbolic cooling tower.

Herman Suryoutomo

Papers

Dynamic analysis of column‐supported hyperboloidal shells

Column Supported Cylindrical-Conical Tanks

Direct dynamic analysis of shells of revolution using high-precision finite elements☆

Stresses in column-supported hyperboloidal shells subject to seismic loading