Life cycle assessment of a residential building: quantity take-off and data input techniques

LCA is a useful tool to assess the environmental impact of buildings. However, to do so accurately requires availability of regional life cycle inventory data, relevant scaling factors and reliable estimation of variables. This paper reports on how building plans, quantity take-off and scaling factors can be used to build an LCA model of a residential building. AccuRate and SimaPro were used to model the data. It was found that the environmental impact varies substantially with the phase of the building life cycle. Varying building life span affects the robustness of results

Use of Markov chain for deterioration modelling and risk management of infrastructure assets

Current annual expenditure for management and renewal of Infrastructure assets around the world is 500 billion US dollars. With an aging stock of infrastructure, innovative methods for management of risk of failure and optimizing of maintenance expenditure becomes extremely important. Whilst different infrastructure assets may have different attributes, governing issues are similar in nature. Prediction of deterioration of some infrastructure is complex since they can constitute of a number of discrete elements with a vast range of influencing factors. A major issue currently faced by local government agencies in Australia is the inability to predict maintenance and replacement expenditure with a reasonable accuracy, which creates situations where emergency repairs would use the funds kept for routine maintenance, which then creates a vicious circle of deterioration

Predicting the remaining life of timber bridges

This paper documents the current state of knowledge relating to the deterioration of timber bridges in Australia. The aim of this research, was to comprehend the present state of knowledge regarding maintenance of timber bridges and address any gap in knowledge. This involved: identifying key defects in timber, investigat-ing the inspection methods utilised to detect these faults and finding the preven-tive measures used to mitigate bridge deterioration. Enclosed are figures which demonstrate how simple industry practices and procedures implemented by each states’ governing authority can reduce these impacts and concludes with an em-pirical model for predicting the remaining lifespan of a bridge

Analysis of flood impact on reinforced concrete(Pre-stressed) girder bridges – a case study

In recent years, frequencies of flood events in Australia have increased. It is noted that flood events cause the most damage to infrastructure compared to any other natural hazards in the world. Bridge structures located over waterways are prone to failure under flood events. Failure of a bridge can impact on the community significantly by reducing the evacuation capability and recovery operations during and after a disaster. A recent research project commenced at RMIT University aims to examine failure of road bridges under flood events. The paper has reviewed different bridge design codes used over several years in Australia for designing the bridges. Various failure mechanisms of bridges due to flood events have been investigated and the most common failure mechanisms of the bridges in Queensland have been identified by examining bridge inspections conducted after the 2011 and 2013 flood events. A case study bridge, which failed under flood loading, has been modeled and the effects of different flood scenarios have been investigated. The impacts of different types of debris, urban and regional, have also been studied. Damage indices have been derived for a concrete girder bridge to demonstrate the methodology for vulnerability modeling of bridge structures

A reliability based approach for sustainable management Of public buildings

Management of aging community buildings is a major cost to many local government organizations in Australia. One of the major challenges is integrating physical or engineering condition ratings with the sustainability issues and community service driven parameters. A new research project continuing at RMIT University in Melbourne is exploring an innovative reliability based approach for deterioration prediction and decision making for sustainable management of community buildings. The paper will present the practices adopted in management of community buildings by six local government agencies in Australia, identifies the community needs and gaps in knowledge. A new integrated methodology for management of community buildings is presented as well as the development of a software tool for implementation of the methodology in local government. The tool covers a building hierarchy, condition monitoring method, deterioration prediction and a decision making process

Seismic resilience of retrofitted reinforced concrete buildings

The fundamentals of the seismic resilience and evaluation method are presented. The evaluation is based on a non-dimensional analytical function for loss variation and a linear recovery function for a community in an average state of preparedness within a specified 'recovery period'. The loss function is a normalized function where the drop of functionality right after the extreme event. The formulated framework, applied for a complex system of six hospitals (considering direct and indirect losses), is employed for low and medium-rise retrofitted reinforced concrete buildings in which the seismic performance has been evaluated by the displacement-based design method. Although this type of design prevents loss of people life it cannot maintain functionality or limit damages. A newly developed Resilience-Based Earthquake Design is promising to address these demands. This research shows that the FRP retrofit is more effective than steel bracing in terms of improving performance and ductility in low-rise RC buildings and the measuring seismic resilience shows an enhanced value as opposed to the un-retrofitted structure

Comparison of three HVAC systems in an office building from a life cycle perspective

This study aims to explore the life cycle environmental impacts of typical heating ventilation and air condition (HVAC) systems including variable air volume (VAV) system, chilled beam system and underfloor air distribution (UAD) system through a case study based on an RMIT office building. Life cycle assessment (LCA) is employed to evaluate the environmental impacts associated with different life cycle phases of HVAC systems. Using carbon emissions as the environmental indicator, ranges of impact for each HVAC system in different life cycle stages are calculated and compared based on the information uncovered in the literature review and relevant LCA inventory database. The system designs on case study are outlined based on the characteristics of a case building. The building was originally equipped with VAV system and was then designed with the chilled beam system and UAD system for comparison purposes. The lists of materials and products used in these three HVAC systems are illustrated, forming the basis of the life cycle assessment. Inventory analyses diagrams have been established based on the activities of HVAC systems in four life cycle stages: manufacturing, construction, operation & maintenance, and demolition. Calculation methods for carbon emissions are established. In particular, inventory data have been developed for manufacturing of HVAC products as well as transportation. We found that the environmental impacts between these three HVAC systems are found to be of different magnitude in different life cycle phase. For instance, the embodied energy of UAD system is the lowest in manufacture stage while that of the chilled beam system is the highest. However, chilled beam system has much more energy saving potential than the other two air conditioning systems in operation stage, and also from a life cycle perspective, the chilled beam system has the lowest environmental impact over a 50 year time frame, and VAV system has the highest environmental impact among the three HVAC systems compared

Incorporation of biosolids in fired clay bricks

In Australia, thousands of tonnes of biosolids are produced and millions of dollars expended for their management annually. Biosolids are derived from wastewater sludge which is the major solid component collected from the wastewater treatment process. This study investigated the incorporation of biosolids into fired clay bricks. Geotechnical characteristics of three biosolids samples produced from Eastern Wastewater Treatment Plant (ETP) in Melbourne were investigated to assess their suitability as a partial replacement material for the clay in fired-clay bricks. Results of classification tests including liquid limit, plastic limit and sieve analysis indicated that the three biosolids samples are silty clayey sand with low to high plasticity. Linear shrinkage of biosolids samples varied from 10% to 15% and organic content from 6% to 14%. Control clay bricks with 0% biosolids and clay-biosolids bricks with 25% by weight biosolids were made and properties including compressive strength, shrinkage, density, initial rate of absorption (IRA), water absorption, thermal conductivity and other properties were determined. The overall results of this preliminary study are promising. Some of the results of this stage of this investigation are presented and discussed in this paper

Shifting qualitative approach in condition monitoring of bridge assets toward a quantitative approach

Many existing transportation infrastructure assets such as bridges, overpasses, underpasses, causeways and culverts in developed metropolises are aging and health monitoring data is now becoming a critical aspect when it comes to evidence based maintenance budgeting. Such infrastructure assets are owned and managed through different authorities representing local, regional, state and national levels of governance. Even in the current practice, especially at local and regional level, condition monitoring is predominantly qualitative and as such labour intensive and assessment is subjective. This raises some questions with regard to the decision making processes in budgetary allocations. This paper presents an insight to the current process of qualitative condition monitoring, based on Australian practices, and the quantitative approach covers through a literature review. Advanced methods of real time condition monitoring using remote sensing are also discussed although such modern techniques are currently being limited to large, recently constructed bridges which are relatively young bridges

Evidence-Based Reviews: History, Utility, and Application

Performing evidence-based reviews (EBR) is a growing and important area of research, and more graduate students should be educated in this area. EBRs provide conclusions based on science and follow a specific methodology to decrease bias, consider all pertinent science on the topic, and have transparency. This thesis is two-fold and includes: 1) a faculty course manual on how to facilitate a college course on EBR and 2) an EBR manuscript on the utility of nutrition labeling to affect consumers’ ability to select more nutritious products and whether or not nutrition labeling can affect purchase and consumption of more nutritious products. This EBR is timely in that the US Food and Drug Administration (FDA) has called for a moratorium on Front-of-Pack labeling (FOP) until two Institute of Medicine Committees have produced their reports and FDA has interpreted those reports. The intention of the manuscript is that it will aid in this interpretation. Of 978 articles collected, 699 were excluded using exclusion/inclusion criteria, 253 were identified as secondary articles, and 26 were used for the EBR. Results: Ten studies answered question #1 on whether or not consumers can pick a more nutritious product by reading labels and 21 answered question #2 on whether consumers actually change their purchasing and/or eating behavior by using labels. Studies ranged from simple cross-sectional studies that used survey data to more complex studies that collected sales data or performed in-store observations. In conclusion, consumers are able to use food labels to pick more nutritious products. Preliminary evidence suggests that a subset of health conscious consumers will read food labels to select a healthier product within a product category. Less evidence exists that reading labels actually results in a change of food intake. More intervention rather than survey studies are required to address this issue. In addition, the next stages of investigation should include looking at the whole diet, rather than just individual foods, and finally what affect the whole diet may have on overall health