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Determination of the early-age compressive strength of concrete is essential for quality assurance, safety, and economy of construction projects. Due to manual operation on construction site, conventional maturity meters are not efficient for live monitoring of the early-age concrete strength. Higher levels of automated and computerised improvements have been made possible by recent developments in wireless communications, sensor technologies, and data processing methods across the construction industry. For real-time monitoring of the early-stage concrete strength, the current study presents an innovative Internet of Things (IoT)-enabled system developed by concrete data sensors (CDS), an Australian-owned private business. The CDS sensor system (the system) communicates with temperature sensors via long-range wide-area network and is linked to a cloud-based platform for data storage. The suggested system’s effectiveness was assessed using three concrete mixtures and developed maturity relationships. It was observed that the predicted early-age compressive strength of the mixes matches well with the actual compressive strength and that the system can effectively automate the characterisation of maturity.

This paper presents the capacity and structural behaviour of hardwood veneer-based circular hollow sections (CHS) tested in bending, shear and compression. The sections were manufactured from early to mid-rotation (juvenile) Gympie messmate (Eucalyptus cloeziana) plantation thinned logs. In total twenty-one 167 mm Outside Diameter (OD) × 1.2 m long CHS were manufactured in seven sets of three nominally identical sections. Two different wall thicknesses were investigated to produce nine compact and twelve more slender cross-sections. The sections were also manufactured in three different structural grades. A sudden failure mode was observed in the compression zone of the slender sections tested in bending. In compression, the compact sections showed a ductile behaviour, while the slender sections showed a more brittle behaviour, with the sections bursting into longitudinal strips. While a relationship was observed between the bending and compressive capacities, and the structural grade, no such relationship was noticed for the shear capacity. Comparison to steel and concrete sections of similar outside diameter proved that the timber sections are the most efficient in terms of bending and compressive capacity to linear weight ratio. The timber sections fall behind their steel and concrete counterparts in terms of shear efficiency, however they still have enough shear capacity for representative structural applications.

Benefits to the construction industry through the use of off-site manufactured (OSM) buildings are well documented. However, and like most innovations, the uptake of OSM has been rather slow. While relevant potential improvements and barriers are widely discussed in the literature, there is a gap in understanding how key project stakeholders (i.e. clients and manufacturers) perceive the value created by adopting OSM into their projects. This paper attempts to fill that gap by developing a value-based model, with its constituents firmly rooted in the seminal literature. The model depicts factors critical to value-creation from both product and process perspectives, allowing for causal relationships among all the inputs and outputs. A systems approach was adopted where causal relationships involving key identified stakeholders are modelled. Industry consultations have led to the identification of the levels of influence and dependency that each factor has on the value creation process.

The construction industry provides extensive impacts to the environment with population increases further driving these pressures. In an attempt to mitigate these impacts, the industry as a whole has promoted and developed numerous green building rating systems (GBRS). These GBRS assign scores to buildings based on a variety of assessment criteria to determine a structures environmental impact. Previous research has identified shortfalls in certain areas related to these GBRS. In order to gain further insight into these systems an industry survey was conducted to establish an alternate perspective. The outcomes of this survey were consistent with that of previous research, identifying the requirement for an increase in the Embodied Energy (EE) consideration of structures in GBRS. The average estimation of the contribution of EE to a structures life cycle consumption was 28.4%. The survey findings also identified a number of other key areas through which changes in the consideration of sustainable development could be improved. The use of these findings and their comparison to previous research outcomes would assist in the development of supplementary mechanisms to improve the assessment of the environmental performance of structures.

Construction material consumption is greater than any time in history. Australia produces approximately 30 million tonnes of finished building products each year, with over 56% of this quantity, by mass, being attributed to concrete and a further 6%, steel. Globally, 23 trillion kilograms of concrete alone is consumed annually, with growing population driving increasing demands. This study assesses the environmental performance of various concrete slab systems. Historically, the focus of environmental performance in buildings has been Operation Energy (OE) requirements, however Zero Energy Buildings (ZEB) are changing this. Specifically the study investigates the environmental performance of concrete structures varying design parameters and construction techniques to optimise its embodied energy (EE). These structures are designed in accordance with all relevant Australian codes and standards. The various slab systems investigated include: beam & slab, flat slab and flat plates while concurrently considering the use of conventionally reinforced and post-tensioned construction methods. Designs were compared in terms of EE outcomes given fixed design criteria, with results indicating reductions between 23.7% and 49.1% when utilising post-tensioned construction methods.

Summary The incorporation of sustainable development (SD) principles into all industries is increasingly important. The contribution of the building industry to a wide range of environmental impacts is extensive with the construction, operation and maintenance of buildings accounting for approximately 50% of all energy usage and anthropogenic greenhouse gas (GHG) emissions globally. In the building design process, structural engineers play a limited role in the sustainability of a design. The decisions on the incorporation of such aspects are usually at the mercy of the architect and client. A literature review was conducted to record and present the variability in research on issues directly related to the environmental performance of structures. There are inconsistencies in the published contribution of embodied energy (EE) and proportion of life cycle energy usage in structures. Outcomes demonstrate that due to this variability, environmental performance of structures is difficult to validate. A systematic approach beginning with standardized calculation procedure and database generation for EE of building materials is essential for practitioners to deliver sustainable structural designs. An analysis of a typical concrete office structure indicates potential benefits through the use of quantifiable environmental performance measures, delivering efficient solutions. Comparisons of slab construction techniques indicate overall EE reductions up to 40% being achievable. Copyright © 2014 John Wiley & Sons, Ltd.

There is currently growing interest in quantifying the direct and indirect carbon emissions embodied in construction materials and their components production. Previous research shows that indirect emission could be higher than direct emission for energy intensity materials such as cement and steel reinforcement. Quantifying direct emissions alone would underestimate the carbon emissions associated with a material and in turn its environmental impact. The assessment of indirect emissions is a challenging task involving upstream processes of material production. This paper investigates the existing literature on the quantification of embodied carbon by both direct and indirect emissions as well as demonstrating the application of a hybrid life cycle assessment method in building construction. The focus of this paper is the Malaysian context however the principles apply universally. A typical 2-storey residential building has been investigated to determine the total carbon emissions when comparing two construction techniques: conventionally reinforced concrete and precast concrete panels. This paper demonstrates the application of hybrid life cycle assessment by expanding the boundaries of process methods and reducing the sensitivities of I–O life cycle assessment to the raw material price fluctuation for product manufacturing.

The main aim of this research is to utilise the focus of sustainable design to compare the material and subsequent environmental impacts of multi‐storey structures situated in Australia. The structure types under investigation were characterised by post‐tensioned and conventionally reinforced floor and roof flat plate slab systems. The foundation designs are undertaken for isolated spread footings on 32 structural model types with constant external dimensions which were composed of floor and roof slabs of varying concrete strength, span length and construction method, with all footing designs providing equivalent structural performance. The results from this study have reinforced the evidence that post‐tensioned construction can have significant effects in reducing material requirements and provide increased structural and environmental efficiency. Through reducing the frame mass, the footing systems were able to be designed using significantly less embodied energy when compared to the reinforced concrete structures. It is also noted that further investigation in the foundational requirements of these models is warranted, with the need to investigate the use of mat foundations for cases where isolated spread footings have required more than 50% of the structural plan area and for the footings that have required excessively thick sections to resist large shearing actions for larger spanned cases at 10 and 13.33 m.

Modular construction methods have been adapted globally for the past few decades and are becoming more common due to their ease of use and flexibility. Structural connections between modules are required for integrity and robustness but details vary depending on the form of the module and the particular application. The behaviour of connections in analysis and design of modular buildings should particularly be taken into account in detail because of their effects on the distribution of internal forces and on structural deformations. The purpose of this paper is to present and analyse the behaviours of an innovative steel bracket connection. Experiments, including shear loading and simply supported tests, were carried out to establish directly the ultimate resistance as well as failure modes of the connections. The finite element software, Strand7, was subsequently utilised to produce models for comparison with test results. A parametric study has been carried out to investigate the effects of varying bolthole dimension and bolthole spacing on the structural behaviours of the steel bracket connection using linear analysis. The model presented in this paper was formed as a baseline for future in-depth investigations to ensure design optimisation of the steel bracket connection.

The purpose of this research is to propose a design technique of concrete mix proportions satisfying service life through genetic algorithm (GA) and neural network (NN)

Vertebral hemangioma is the most common spinal axis tumor. This rare presentation of a vertebral hemangioma extended contiguously from one cervical vertebra to another, encasing the vertebral artery, and thereby mimicking other tumors of the spine. We discuss the differential diagnosis of bridging vertebral masses.

This research determines environmental advantages achievable through application of alternate concrete slab construction methods for a typical concrete office building. The collaborative pilot study has been conducted to compare the significant material reductions on alternate slab systems to improve sustainable design methods. These structures were designed in accordance with all relevant Australian standards, incorporating with various concrete strengths and various geometric parameters such as number of columns, spans with respect to slab thickness. The results indicated that environmental advantages are achievable through the application of alternate concrete slab construction methods for the typical office structure. Analysis results indicated an 18.2 to 37.0 % reduction in concrete volume and 21.0 to 43.6% reduction in steel mass for the post tensioned structure to compare with the conventional reinforced concrete slab. Similar results were observed when comparing reductions in embodied energy 28.1 to 40.9%.

The paper presents the ongoing research which aims to develop a life cycle energy assessment (LCEA) methodology for systematic estimation of embodied energy (EE) and carbon emission (CE) in building and construction processes in Malaysia. On top of that, this will include environmental and economic aspects of EE and CE, which involves of "carbon-added" and "value-added" at each stage of the supply chain. The paper purpose the methodology to identify and quantify the EE and CE in the construction in Malaysia. The methodology includes calculating environmental and economic impacts of life cycle carbon inventories, incorporating "carbon added" and "value-added" along the whole supply chains, accounting for the background economy in which activities are embedded. A particular novelty of this research is that it develops an integrated methodology and a set of tools that will systematically assess of environmental and economic implications at each stage of the supply chain.

In Australia, approximately 30 million tonnes of finished building products are produced each year, with over 56% of this quantity, by mass, being attributed to concrete and a further 6%, steel, highlighting the importance of maximising design efficiencies. The cement industry has been reported responsible for 5% of global carbon dioxide emissions while the construction, operation and maintenance of buildings are estimated to account for 50% of all energy usage and more than 50% of all anthropogenic greenhouse gas (GHG) emissions globally. This research determines some environmental advantages achievable through application of alternate concrete slab construction methods for a typical 10-storey office structure. Structural analysis results indicate a 36.9% reduction in concrete volume and 43.4% reduction in steel mass in a post tensioned slab structure in comparison with a conventional reinforced slab system. Similar results were observed when comparing reductions in embodied energy and global warming potential. These results highlight the improvements possible by the incorporation of improved sustainable design methods Paper presented at the 22nd Australasian Conference on the Mechanics of Structures and Materials (ACMSM22) held in Sydney Australia, from 11-14 December 2012