Rolled steel plates were subjected to ultrasonic inspection in order to examine acoustical anisotropy and non-homogeneity along the thickness direction. Two vertical planes of the plate were observed under a microscope in order to investigate changes in microstructure. Shear wave velocities, which depend on both propagation and polarization directions, were measured for both 40 mm and 26 mm thick steel plates. Changes in the shear wave velocities V_L are found along the thickness direction. Especially, strong local anisotropy is found due to elongated ferrite grains in the near-surface zone. A high angle beam probe should be used carefully for ultrasonic testing on a plate exhibiting strong anisotropy.

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This research aims to determine the effect of loading pattern on the damage of a reinforced concrete bridge column. Five specimens were tested with uni-directional or bi-directional cyclic loading patterns combined with a uniform axial load. From the test results, the theoretical plastic hinge zone length was calculated considering the yield penetration effect and the energy dissipated by the specimens was obtained.

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By its geometrical nonlinearity, the realization of a desired suspension structure depends on the shape-finding procedure. In an actual suspension structure, cable members are usually combined with bending members. For a beam-cable structure, in this study, the displacement method is employed to deal with the structural equilibrium, but in which each cable member is treated as the elastic catenary through a force-method computation. Thereafter an iterative scheme of shape finding is developed for such a mixture of cable and beam members, which is based on the tangent coefficients to change of the cable natural lengths on each updated equilibrium configuration.

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The purpose of this study is to identify the causes of fatigue cracks found in a plate girder-on-steel frame pier bridge. The complexities of this type of structure make the stress configurations near crack locations complicated. A three-dimensional finite element model, incorporating both superstructure and substructure was created to study the stress development mechanisms near crack locations. Field tests were carried out to investigate structural behaviors, such as conditions of bridge bearings, and to validate the finite element modeling. The results indicate that fatigue cracks are caused by dysfunctional bridge bearings, poor structural details and deformations of some members.

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A swarm of earthquakes began in the northern portion of the Gulf of Aqaba on November 22, 1995 with amaximum local wave magnitude of M_L 6.2 and focal depth of about 15 km, causing damage to buildings in the Aqaba region. More than 8000 after shocks were recorded during the next 40 days. Observations related to damage to structures and soil liquefaction are presented by photos and discussed. Generally, engineered low-rise buildings with one to four stories above ground behaved satisfactorily. The hotel area in Aqaba on the shoreline appears to be riskier for flexible buildings during major earthquakes. Therefore, denser inland alluviums or rock sites should be considered for constructing new high-rise buildings and hotels.

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The development of a nonlinear homogenization for media having lattice-like periodic microstructure is presented. For continuum media, conventional homogenization methods lead to classical continuum boundary value problems at both micro- and micro-scales. However, discretizing latticelike micro-structures, such as cellular solids, by frame elements is a natural step. The main difficulty in applying frame elements to micro-scale problems is inconsistencies between the kinematic field of the frame elements and the micro-scale displacement field. Numerical examples of cellular solids demonstrate the feasibility and strengths of the computational efficiency of the method presented.

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