Since the mid-1960s when the forms of curved shell finite elements were originated, including those pioneered by Professor Gallagher, the published literature on the subject has grown extensively. The first two present authors and Liaw presented a survey of such literature in 1990 in this journal. Professor Gallagher maintained an active interest in this subject during his entire academic career, publishing milestone research works and providing periodic reviews of the literature. In this paper, we endeavor to summarize the important literature on shell finite elements over the past 15 years. It is hoped that this will be a befitting tribute to the pioneering achievements and sustained legacy of our beloved Professor Gallagher in the area of shell finite elements. This survey includes: the degenerated shell approach; stress-resultant-based formulations and Cosserat surface approach; reduced integration with stabilization; incompatible modes approach; enhanced strain formulations; 3-D elasticity elements; drilling d.o.f. elements; co-rotational approach; and higher-order theories for composites. Copyright © 2000 John Wiley & Sons, Ltd.

A survey of recent shell finite elements

System identification in structural engineering

Finite element analysis of vehicle-bridge interaction

Diagnostic instrumentation and monitoring of bridges are essential for reliable structural condition assessment and performance evaluation. This management step applies particularly to structurally deficient bridges that cannot be accurately evaluated by inspection and/or analysis alone. Reliable evaluation is an economic and engineering requirement before any decision-making for preventive action. Thus, field diagnostic capabilities are indispensable tools to enable evaluation and support field-calibrated modeling, analysis, identification, and load rating. The reliability of structural evaluation for objective bridge management is determined by the dependable performance of all the system components. Although instrumentation and monitoring procedures appear to be well established, some misconceptions still keep recurring critically in practice. To improve the state-of-practice of structural diagnostics, available field systems and methods need re-evaluation of their instrumentation and monitoring perfor...

Bridge Instrumentation and Monitoring for Structural Diagnostics

The paper presents an experimental study of the actual dynamic effects for a preselected typical highway bridge. Knowledge of the dynamic impact factors is important for accurate determination of the ultimate load capacity and performance assessment of constructed bridges. Static and dynamic field tests were performed on a two-lane concrete highway bridge built in 1999 on U.S. 90 in northwest Florida. During the tests, one or two fully loaded trucks crossed over the bridge, which was instrumented with strain gauges, accelerometers, and displacement transducers. A wooden plank was placed across the lanes for some runs to trigger extensive dynamic vibration and to simulate poor road surface conditions. Data collected from the tests were used for comprehensive assessment of the bridge under dynamic loading. Impact factors obtained from the tests with higher speeds were found larger than corresponding values recommended by bridge codes. Analysis revealed that stiff vehicle suspension, road surface imperfection, and "bouncing" of the truck loading contributed to the high impact factors. Experimental data were also used for validation of the finite-element models developed for the vehicle-bridge system.

Experimental Evaluation of Dynamic Effects for a Selected Highway Bridge

Dynamic structural assessment of a highway bridge via hybrid fe model and in situ testing

A practicable and highly accurate flat shell hybrid element for engineering applications on a PC

A finite element computer system and analysis of a bridge structure

Cost effective high precision hybrid elements are presented in a hierarchical form for vibration analysis of plates. The elements are constructed by introducing computer installed hierarchical element generator algorithms which take advantage of the exact analytical treatment of the energy integrals automatically. Additional benefits accrue from: (i) the careful selection of assumed stresses and displacements satisfying finite element requirements, and maintaining the correct stiffness rank and invariance; (ii) the ability to reduce computational costs associated with various operations and the independence with respect to element geometries, which serve to build up a methodology to handle the generation of finite elements in any general purpose finite element system efficiently. Extensive numerical studies are made to predict the natural frequencies and harmonic response of plates with different boundary conditions. Accuracy of the solutions is assessed by comparison with the well established results. The noteworthy aspects of the applications are that the proposed elements are faster than those cited previously, and show a more favourable comparison to the analytical solutions for a wider range of vibration modes by maintaining rapid convergence characteristics.

H. Alaylioglu

Papers

Dynamic structural assessment of a highway bridge via hybrid fe model and in situ testing

A practicable and highly accurate flat shell hybrid element for engineering applications on a PC

A finite element computer system and analysis of a bridge structure

Effective hybrid hierarchical element generator for vibration analysis of plates

Hybrid plate vibration models for coarse-mesh analysis