The continuous developments of Building Information Modelling (BIM) in Architecture, Engineering and Construction (AEC) industry supported by the advancements in material resourcing and construction processes could offer engineers the essential decision-making procedures to leverage the raising demands for sustainable structural designs. This article brings together the theory of Life Cycle Assessment (LCA) and the capabilities of BIM to survey the current developments in the energy efficiency of structural systems. In addition, the article explores the engineering dimensions of common decision-making procedures within BIM systems including optimisation methods, buildability limitations and safety and code compliance checks. The research presents critical expositions in both the engineering and sustainable energy domains. The article then argues that future innovations in the sustainable decision-making of buildings' structures would require BIM-integrated workflows in order to facilitate the conflicting nature of both energy efficient and engineering performance indexes. Finally, the study puts forward a series of research guidelines for a consolidated decision paradigm that utilises the capabilities of BIM within the engineering and sustainable energy domains in a synergistic manner.

Bender elements are piezoelectric transducers frequently employed for the measurement of the small-strain shear modulus of soils. The measurement is based on transmission of a mechanical signal through a soil sample. A very common set-up involves transmission along the axis of a cylindrical sample, with source and receiver transducers mounted, for instance, in the end platens of a triaxial apparatus. Current test interpretation is generally based on the assumption of plane wave transmission between transducers. However, this model does not explain the heavily distorted transmission usually observed. The result is substantial measurement uncertainty. Although other phenomena do play a role, it is here proposed that a main culprit for signal distortions is sample-size effects due to lateral boundary reflections. To support this hypothesis, results from a series of numerical 3D simulations of the problem are analysed. Velocity estimates obtained from the simulated traces using plane-wave based time and frequency domain methods are compared with the known exact value. Errors in velocity determination are shown to be very important and directly related to lateral boundary influences. Comparison with some experimental data confirms the need to include sample-size effects in a renewed interpretative framework for bender tests.

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Shear modulus measurement using bender elements in laboratory samples has become very popular. However, the test results are hard to interpret. Simple plane wave test models are too coarse and result in substantial measurement uncertainty: near 100% in G0. A possible refinement of the test model is based on Stokes's fundamental solution for an isolated source. Near-field effects appear, and they have been regularly quoted as a major source of uncertainty in tests. There are some criteria in use for avoidance of near-field distortions, but they are signal dependent and not always successful. After some consideration of Stokes's fundamental solution the authors propose a new frequency domain signal-independent criterion to avoid near-field effects. Time-domain criteria are also given, but they are shown to be signal dependent. Applying this criterion to some experimental results the authors then also show how near-field induced errors are not responsible for much of the observed signal distortion. Uncertainty in signal arrival lasts well beyond the end of the Stokes source near field.

Abstract. Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.

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