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The New Zealand Building Code (NZBC) is performance based. From a durability perspective, compliance requires a practitioner to demonstrate that materials will remain functional for the minimum periods specified. The NZBC also states that buildings must be constructed to avoid the likelihood of fungal growth or the accumulation of contaminants on linings and other building elements. Currently, there is no recognised method for practitioners to use to demonstrate that a wall system can meet this requirement for the required design life. In this paper, we consider how hygrothermal modelling, in conjunction with the VTT mould index, may be used to form the basis of such a method. In the past, there has been a discrepancy between predicted failures and field evidence, but the VTT mould index appears to correlate much better with the successful in-service history of typical New Zealand construction. [ABSTRACT FROM AUTHOR]

Construction professionals agree that building information modelling (BIM) will revolutionize the architectural, engineering, and construction (AEC) industry and its impact will be felt by all project stakeholders including owners and facility managers. Statistics show that many owners and other stakeholders perceive BIM as a technology that can make project delivery more efficient because it allows project information to be fully integrated. In the future, owners are expected to demand the use of BIM to prevent over-budget and over-time project delivery. However, as we are preparing this contribution the level of implementation and use of BIM varies widely across the globe. This paper probes the state of BIM in Alberta from three points of view: ( i) the current understanding and implementation, ( ii) the motivations driving its use, and ( iii) the challenges hindering its implementation. The findings of this paper are extracted from individual responses to a web-based survey that was proposed to professionals in the Albertan AEC/FM industries. [ABSTRACT FROM AUTHOR]

Masonry blocks are usually made of Portland cement and cured by steam. This study explores the possibility of making masonry blocks using steel slag as binder and carbon dioxide as curing activator. By carbonation activation of steel slag blocks, carbon dioxide can be permanently sequestered in steel slag as calcium carbonates, leading to stronger and more durable construction blocks. In this paper, carbonated steel slag paste was first evaluated by thermogravimetry, derivative thermogravimetry, X-ray diffraction, carbon uptake, strength development, and leaching tests. Based on the preliminary results, the full-size masonry blocks were fabricated using steel slag as the binder and granite as the aggregates. The physical properties and durability of full-size steel slag masonry blocks were then examined through their density, water absorption, moisture content, compressive strength, and fire resistance. An economic analysis was performed and a carbon dioxide utilization capacity was estimated. This study demonstrates that production of steel slag masonry blocks by carbonation is an economically feasible way to utilize carbon dioxide. [ABSTRACT FROM AUTHOR]

Construction companies need a knowledge management system to collate, share and ultimately apply this knowledge in various projects. One of the most important elements that determine the time estimates of any construction project is productivity. Such projects have a predilection towards uncertainty and therefore require new generation of prediction models that utilizes available historical data. The research presented in this paper develops, using fuzzy approach, a knowledge base to analyze, extract and infer any underlying patterns of the data sets to predict the duration and productivity of a construction process. A six-step protocol has been followed to create this model: ( i) determine which factors affect productivity; ( ii) select those factors that are critical; ( iii) build the fuzzy sets; ( iv) generate the fuzzy rules and models; ( v) develop the fuzzy knowledge base; and ( vi) validate the efficacy and function of these models in predicting the productivity construction process. The fuzzy knowledge base was validated and verified using a case study and the results were satisfactory with 92.00% mean validity. In conclusion, the developed models and system demonstrated the ability of a knowledge base management to predict the patterns and productivity of different construction operations. [ABSTRACT FROM AUTHOR]

Developing a holistic and accurate delay analysis software is still challenging the current delay analysis practices. Most of the existing delay analysis techniques are not programmed and still depend on manual calculations. The currently available computerized delay analysis techniques are still limited, suffer from many drawbacks, and do not consider many of the delay analysis situations. This paper introduces web-based software called total float management (TFM) software for analyzing delay claim utilizing TFM delay analysis technique. The TFM technique depends on day-by-day analysis, which gives more accurate analysis over other techniques. The software has the ability to import schedule data from Primavera P6 and Microsoft Project (MS project) software in various formats. This feature makes analysis easier and reduces the time required for data input. Many other features are included in the TFM software, such as the ability to address concurrent delays, change orders, and acceleration events. [ABSTRACT FROM AUTHOR]

Considerable work has been carried out on risk qualitative and quantitative assessment but far less on risk identification. This paper introduces a newly developed method for risk identification, based on micro risk breakdown structure and newly introduced identification procedure called preventive root cause and effective remedial. It also introduces a risk responsibility matrix that distributes the responsibilities associated with each risk among project stakeholders and introduces a newly developed method for qualitative and quantitative assessment of each item using fuzzy set and fuzzy probability theories. Output of the proposed assessment method is pre-mitigation contingency of each risk which represents a quantitative indicator for decision making whether to mitigate or not the risk being considered. Two case studies and one numerical example are presented to demonstrate the applicability and illustrate the essential features of proposed identification, allocation, and assessment methods. [ABSTRACT FROM AUTHOR]

There has been increasing interest in international construction since the late 1990s due to growing competition in global markets. A bibliometric analysis of international construction research is conducted to evaluate the trends and to map the productivity in the field. Using the Scopus database from 2003 to 2013; document type, research performance of leading journals and authors, geographic and institutional distribution of research is assessed. The core and sub topics of the literature is also analyzed to determine critical themes in international construction. Results reveal that (1) risk management, (2) measuring performance, (3) general strategy and (or) competitiveness, and (4) foreign market entry decision are the top four core themes in international construction research. The fluctuations in the number of papers in different subject categories reflect the new tendency in international construction debate, which emphasizes a shift from measuring performance themes to general strategy and (or) competitiveness and foreign market entry decision in international construction. [ABSTRACT FROM AUTHOR]

Traditional steel connection systems rely on on-site welding and bolting, which are labor intensive and require skilled craft workers. Reducing welding and bolting efforts in structural steel erection presents an opportunity to improve steel structure construction productivity. A series of steel quick connection systems (SQCS) have been introduced in the market in the last few years, either through research prototypes or commercial products. However, their real benefits need to be confirmed and quantified at actual construction sites. Hence, the main goal of this study was to evaluate the impact of steel quick connection systems on construction productivity and cost. To accomplish this goal, the authors performed analyses of data from nine SQCS projects and conducted two case studies. The authors also utilized a building information modeling based simulation to compare the schedule impact of SQCS and conventional structural steel connections systems. This paper describes the details of this study and its findings. [ABSTRACT FROM AUTHOR]

Parameters (factors and practices) influencing construction labour productivity are multi-faceted and project dependent. A proven measurement scheme and modeling approach to investigate the effect of parameters on construction labour productivity has not yet been developed. This study identifies key parameters influencing labour productivity using context-sensitive surveys that reveal contextual differences between key parameters. The study relies on data collected through 141 surveys administered to project management and trade respondents from six Canadian projects in either of two contexts: building and industrial. Analysis revealed the top parameters influencing labour productivity on building and industrial projects. Consensus between project management and trade level respondents regarding parameters' effects within and between contexts was evaluated using statistical analysis; results indicated some differences in perception. The methodology and findings from this paper are useful for identifying enablers of and barriers to better productivity, developing context-sensitive labour productivity models for use in analysis, and developing productivity improvement strategies. [ABSTRACT FROM AUTHOR]