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Steel poles are extensively used as street light posts and various other applications within the power distribution network. For partially buried pole, the effect of corrosion below and at the ground level significantly controls the overall load capacity. In this study, number of in-service steel pole specimens extracted from field were assessed for the corrosion damage. The level of corrosion was estimated by remaining wall thickness measured using ultrasonic testing and the surface corrosion was estimated using 3D laser scanning to adopt an appropriate existing model for buried steel structures. A relationship between maximum and average corrosion pit depth and loss of embedment depth was then developed. Finally, the corrosion parameters, combined with uncertainty in loading and soil properties were employed to perform time-dependent reliability assessment for steel light poles which can be used to assist the asset maintenance team in planning the replacement or strengthening works for steel pole.

This paper discusses the derivation of a set of dynamic load factors for calculation of walking response on the basis of measurements made during a biomechanics research carried out with young adults. Firstly, a quite large number of experimental data on single footstep force were collected. The single footstep forces were then superimposed to generate the force time history for a continuous walk. This was followed by the transformation of the resultant force to the frequency domain from which the dynamic load factors for the first ten harmonics of a pacing rate can be extracted. A statistical analysis was employed on the dynamic load factors to acquire their design values in terms of the 90-th or 95-th percentile. The waking force function recommended by various design guides and that developed in the paper were then used in a comprehensive finite element model to predict the vibration level of a building floor. Current design guides on floor vibration normally suggest using four harmonics in the walking force whereas load factors for ten harmonics were developed in this paper. The acceleration response of the floor was found to increase by 5-33 % when walking harmonics beyond the fourth harmonic were considered. The inclusion of higher harmonics would therefore lead to a more conservative estimation of the floor response.

Microwave modeling and simulation are essential to designing microwave circuits and systems. Although fundamental concepts and approaches for modeling and simulation are mature, the drive to higher frequencies, tighter design margins, and more functionality/complexity of circuits continue to defy the capabilities of existing modeling and simulation methods. Newer algorithms are being developed to address the speed, accuracy and robustness of design algorithms. Coupled with the advent of more powerful computers and algorithms, microwave design automations are solving much more complex problems in much shorter time than previously imaginable. This paper describes the advances and state-of-the-art in automated modeling and simulation. Automated data-driven modeling approaches covering data sampling/generation, model structure adaptation, and model training/validation are described. Simulation of nonlinear microwave circuits is described covering formulations of simulation equations and advanced solution algorithms addressing problem size, convergence speed and solution accuracy. The descriptions highlight fundamental concepts, advanced methodologies, and future trends of development.

Crossarms are widely used in power distribution and telecommunication sectors to support overhead cables. These structures are horizontally attached to the top of vertically erected utility poles and are essential elements in connecting overhead cables to the poles. Timber is the dominantly used material type for crossarms in the existing distribution networks. Nevertheless, there are alternative crossarms made from steel, composites, polymers, and even from concrete. This paper reviews the studies on the condition assessment of timber crossarms considering the aspects of decay identification and flexural strength assessment. The limitations and shortcomings of the conventional inspection techniques for crossarms are presented. Then, the studies on the developments of non-destructive test methods to address these issues are reviewed. Further, the results from the experimental work conducted to assess the structural capacity of in-service crossarms are presented and analysed. In addition, the possible future advancements of alternative crossarm types are also discussed, considering the mechanical strength, durability performance, and sustainability aspects. This paper aims to highlight the advantages and disadvantages of different condition assessment techniques for crossarms, indicating the importance of an integrated approach combining both the conventional and non-destructive testing techniques.

This paper presents a method for determining values of dynamic parameters of the Hunt and Crossley model in order to estimate the amount of force generated at the point of contact (contact force) in an impact. A two-degree-of-freedom lumped-mass-system based on a non-linear visco-elastic model as proposed by Hunt and Crossley has been widely used to accurately model contact force. The primary difficulty associated with the Hunt and Crossley contact force model is the need to determine the unknown dynamic parameters of the model, which can be obtained by calibrating the model against results from high-speed impact experiments. Spherical impactors have to be placed in the gas-gun barrel for accelerating onto the target specimen. An innovative and inexpensive method proposed in this paper describes the use of compression testing on a test rig employing cylindrical specimens of colliding bodies to obtain the dynamic parameters thereby waiving away the need of costly and time-consuming impact experiments. Method name: Compression testing-based contact force determination methodology, Keywords: Dynamic stiffness, Impact, Hunt and Crossley model

The objective of this paper is to review key issues concerned with the proper engineering of non-structural components in buildings for their safe and satisfactory performances in projected seismic conditions in regions of low and moderate seismicity. Initially, the paper provides an overview of the conventional force-based provisions for the calculation of the required strengths for full restraints of non-structural components. Given the relatively small displacement demand of the ground in conditions of low and moderate seismicity, provisions for protection of non-structural components should only target at items which have been identified to be vulnerable to overturning and their failure can have serious consequences. In this context, the displacement-based (DB) model for overturning and its linearisation is presented. The DB model can potentially become very useful as technical reference when it comes to identifying potentially hazardous items which risk overturning if unrestrained. The paper concludes with a discussion on engineering for earthquake safety in buildings in a broader context than merely regulating the structural design of the building.

While the design and technology of conventional low rise light framed residential structures are relatively simple, their response to lateral loading is quite complex. This is due to the high degree of redundancy, the irregular geometry and interaction between the structural and non-structural components. In addition, the designated lateral bracing elements within one structure may exhibit significantly different behaviour due to the different bracing actions and different materials. This paper focuses on the bracing capacity of plasterboard clad walls which could be considered either structural or non-structural. While such walls may be installed purely as partition walls, they may provide lateral strength and stiffness due to the complex load paths. The paper presents in detail the possible load transfer mechanisms to a variety of typical walls. It also highlights the difficulty with performing racking tests on isolated walls due to the complex boundary conditions surrounding walls in real structures. In addition, the paper reports racking test results that demonstrate the effects of different boundary conditions on the load carrying capacity and the failure modes.