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Light weight concrete has many advantages that can be used in the construction of buildings. Perhaps one of the most important of these features is its light weight, which contributes a lot to reducing stress on the soil, which provides the possibility of rising buildings and increasing the number of floors. In addition to its role in thermal insulation and its impact on reducing the consumption of energy sources in cooling and heating, light weight concrete is considered one of the sustainability factors in buildings. One of the second major factors in sustainability is to reduce or avoid the use of cement in the manufacture of this concrete, because of the harmful effects of cement on the environment and global warming. Cement-free concrete is considered a sustainable material in terms of its depletion of the waste materials and spin-off products from different industries apposite of consumption of natural resources in the cement industry (mud, limestone). In this research first aim is to produce lightweight cement-free concrete using pozzolanic material and montmorillonite clay as coarse and fine aggregate. Studying some properties of producing light weight concrete (density, compression, tensile) with different ages (7, 28, 56) days.

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When applied in the construction industry, a quality management system (QMS) should be implemented to ensure sufficient effort is made to achieve the required levels of quality in constructed projects. Attainment of these quality levels results in customer satisfaction, which is fundamental to ensuring long-term competitiveness for construction companies. However, the construction sector still lags behind other sectors in relation to its successful adoption of QMSs, due to a relative lack of acceptance of, or interest in, these systems among industry stakeholders, as well as other barriers that impede their implementation. For this research, an integrative review of the literature was performed to identify the barriers impeding successful implementation of QMSs in the construction industry, as well as investigating the critical success factors (CSFs) necessary for a more effective adoption of such systems. To date, although many studies regarding these factors have been undertaken in the construction industry context, no key research so far, has comprehensively investigated the impacts of all factors surrounding successful implementation of a QMS in the construction industry building sector (CIBS), especially on the impact of external factors. Also, no specific research has exclusively been carried out to explore the impact of CSFs, particularly when applied at project level. Therefore, this research primarily aims to investigate an inclusive list of factors impacting on QMS deployment in the CIBS by focusing exclusively on the external factors and the CSFs of project level in order to develop a comprehensive framework of QMS deployment. To fulfil the aim and objectives of this research, the study proposed a conceptual framework encompassing those factors identified by literature review analysis, and that indicated the main gaps in the knowledge revealed in this study. This conceptual framework was used to guide the research examination throughout the data collection and analysis stages. This research has adopted a combination of qualitative investigation, data collection and analysis methodologies. This exploratory research was approached by collecting data through interviews and case-studies representing Tier 1 and 2 AustralianCIBS projects. iv In Phase 1 of the research, an exploratory study was undertaken to fulfil first and second objectives of the study through investigating the level of QMS deployment in selected building organisations in South East Queensland in Australia, in order to gain an initial understanding of which external factors critically impact the implementation of QMSs in the CIBS. The study also assisted in providing a comprehensive overview of the CSFs necessary for QMS deployment, especially those that influence the project level. In the next stage of data collection performed to achieve third and fourth objectives of the research, three case-studies were conducted to investigate the level of QMS implementation in the context of these case projects. The examination of the studied cases helped in explaining the multifaceted issues encountered during the adoption of a robust QMS in the CIBS. A number of qualitative-based techniques were used to analyse the collected data. These techniques involved using QSR International NVivo 11 software, patternmatching, explanation-building as well as numerical counts logic. NVivo 11 software was used to support management of the research activities within and across the different phases of the research. In addition, a pattern-matching technique was followed throughout the processes of both within-case and cross-case analyses to compare the propositions developed during the exploratory study analysis with the case studies data, to either confirm or refute these propositions. An explanationbuilding was performed to extend case study ideas for further research through following a series of iterations commenced by creating initial propositions, and then comparing the findings of the initial case against these propositions prior to revising such propositions and comparing them again with the findings of other cases. Finally, numerical counts logic was utilised to rate the utility of each case, constructing a matrix of queries that generated theme-based assertions from all cases, ultimately developing tentative assertions derived from a comparative analysis of the findings of case studies. The exploratory case study interviews emphasised the impact of external factors on the effective deployment of QMS in the CIBS. The study revealed that the implementation of QMS is affected by twelve external factors. The exploratory study also disclosed those CSFs that directly influence the adoption of a QMS that specifically impact at the construction project level. A sum of ten CSFs was identified by carefully analysing the data of the exploratory study. v The within-case and cross-case analyses explained the impact of these factors, the external factors, and the CSFs on the level of QMS implementation necessary in building projects. Assertions emerging from the results of the cross-case analysis were compared with the current literature to develop new insights about how the factors surrounding a QMS impacted on the outcomes of implementing such a system. This has been achieved by categorising the overall factors influencing the deployment of a QMS, based upon their impact and, ranking them in descending order, according to their significance on QMS deployment. This analysis led to the categorisation and of the external factors into drivers and barriers based upon their respective impacts on QMS adoption and implementation and ranking them in descending order. Most of these factors proved to be barriers, whilst two factors were confirmed to be drivers for the adoption of a robust QMS. The CSFs were also grouped into three categories, which grouped together those factors more likely to result in more robust outcomes from QMS deployment. These groups include CSFs at both the organisational and project levels, and CSFs also at both levels. Also, the cross-case analysis led to the ranking of all of these factors according to the significance of their respective impacts on QMS implementation. The main contribution of this research is that a new categorisation of factors is vital for construction companies, in order to develop more precise requirements for QMS implementation and to establish a practical strategy to better facilitate project teams to manage the impacts of these factors. Further, the determination of the ranked CSFs applicable for each level of building organisation is fundamental to implementing a robust QMS, as well as tackling many of the inherent issues applicable in QMS deployment. The overall insights and findings of this research assisted in establishing the fully developed framework for robust QMS adoption. The developed framework represents a comprehensive set of guidelines for the management teams of building organisations to address and maximise the distinct relationships between the effective deployment of QMS and the factors surrounding that implementation. The framework of QMS deployment potentially contributes to the improvement of QMS implementation in the CIBS, which can eventually facilitate delivery of higher quality outcomes. The development of this framework is expected to bring some significant benefits to the Australian construction industry building projects, with respect to qualifying project vi teams, assuring provision of essential resources for QMS adoption, and improving the overall perception amongst construction industry stakeholders of QMS significance.