Planning of Urban Quarters, Districts and Neighbourhoods in Islam’s Holiest City: A Comparative Analytical Study

Global experiences of planning urban areas are characterised by adopting hierarchical structures from large to small structures, i.e. residential quarter (large residential area), residential district and then residential neighbourhood. Each structure is characterised according to the area, the number of people and the services required for targeting a sustainable urban environment. This concept is a milestone in urban planning in Saudi Arabia. The research attempted to discuss the general trend of planning housing projects in Saudi Arabia and the extent of applying the hierarchal concept. Three models were chosen randomly in Makkah, showing such planning hierarchy. These are Al Shawqiyyah, Al Sharaie and Al Rabwah. These projects were planned four decades ago and became a reality. Through comparative analytical methods, findings revealed ambiguity of the hierarchal planning concept in these projects. Further, the traditional neighbourhood concept was prevalent in most neighbourhoods characterised by low-density development in planning but medium and high densities in reality. The problem is getting worse as cities grow horizontally and vertically. Consistent scientific analysis based on practice and continuous meta-analysis was used. The paper calls for the need to change the current premises of housing plans and reorganise the accumulated problems according to global experiences and local standards.

Accuracy and precision of the CSLT measurement system: An experiment to defect diagnoses in bored piles

A new measurement system called Crosshole Sonic Logging Tomography (CSLT) provides information on the size, shape, and orientation of defects in a bored pile. The CSLT measurement system has not (yet) been accredited in Hong Kong for foundation testing. Bored piles in Hong Kong are generally wide and deep. Existing measurement accuracy studies do not consider this large type of bored piles. The objective of this research is to quantify the measurement accuracy and precision of the CSLT method for large diameter bored piles (the most common pile type for public housing projects in Hong Kong). A test pile was constructed with known defects and perform experiments with a CSLT measurement system to quantify its accuracy and precision. CSLT is found to be accurate in detecting shape, size, and location of large defects but small defects close to the tube are difficult to detect. Generally speaking, CSLT has satisfactory accuracy and precision for practical use. The use of CSLT can be considered as a feasible method in defect diagnosis of bore piles in Hong Kong.

Potential and prospects of photocatalytic disinfection: using sustainable solarenergy- driven photocatalysts

A new measurement system called Crosshole Sonic Logging Tomography (CSLT) provides information on the size, shape, and orientation of defects in a bored pile. The CSLT measurement system has not (yet) been accredited in Hong Kong for foundation testing. Bored piles in Hong Kong are generally wide and deep. Existing measurement accuracy studies do not consider this large type of bored piles. The objective of this research is to quantify the measurement accuracy and precision of the CSLT method for large diameter bored piles (the most common pile type for public housing projects in Hong Kong). A test pile was constructed with known defects and perform experiments with a CSLT measurement system to quantify its accuracy and precision. CSLT is found to be accurate in detecting shape, size, and location of large defects but small defects close to the tube are difficult to detect. Generally speaking, CSLT has satisfactory accuracy and precision for practical use. The use of CSLT can be considered as a feasible method in defect diagnosis of bore piles in Hong Kong.

The Role of Value Engineering in Government Housing Projects in Developing Countries to Improve Value

Government housing projects are among the complex issues facing developing countries’ governments. There have been many attempts to solve problems related to this issue and a lot of effort has been made in this direction. The main problem is lowering the cost of lodging, without sacrificing its quality and the effectiveness by which it fulfills the needs of its occupants. This became possible upon the use of the value engineering technique. Value engineering is an effective tool used to solve problems related to housing, by lowering cost on one hand and sustaining or even ameliorating quality and performance.The purpose of this study is to try to identify a series of proposed solutions and value indicators and to describe their role in improving value in government housing projects. This process may assist the designer in choosing and managing, value indicators during the creative phase, using references from the literature and the analysis of case studies.The literature review identified the reasons for high costs and poor performance, which are often a result of a misunderstanding of the fundamental principles of design criteria and value indicators, followed in government housing projects. The review also pinpointed the most important considerations that improve value.Results obtained in this study feature the positive effects of methods under the umbrella of value engineering, applied in government housing projects. It was found that savings of 15% to 40% can be achieved in the total cost of a certain project, using this technique. Generating ideas in the creative phase is one of the most important stages in value engineering studies. A set of value indicators and proposed solutions in the form of a checklist were derived and can be used in the future, during the creative phase of value engineering studies in the initial design stage of government housing projects.

Evaluating the key risk factors in PPP-procured mass housing projects in Nigeria: a Delphi study of industry experts

Purpose The purpose of the study is to elicit risk factors that are peculiar to public-private partnership (PPP)-procured mass housing in Nigeria from the expert perspectives in ensuring the success of the scheme thereby reducing housing deficit in the country. Design/methodology/approach The risk inherent in construction projects had been established through literature in general. The risk in PPP projects is emerging because of the recent acceptance of the procurement option by governments all over the globe. The Nigerian Government has also adopted the procurement option in bridging the housing deficit in the country. This study, therefore, conducts a Delphi survey on the probability of risk occurrence peculiar to PPP mass housing projects (MHPs) in Nigeria. Pragmatic research approach through the mixed method of both quantitative and qualitative methods was adopted for this study. The quantitative method adopts the administration of questionnaires through the Delphi survey, whereas the qualitative method used interviews with the respondents. A two-stage Delphi questionnaire was administered to construction practitioners that cut across academics, the public and the private sectors by adopting convenient sampling techniques and following the Delphi principles and procedures. A total of 63 risk factors were submitted to the expert to rank on a Likert scale of 7 and any risk factors that the mean item score (MIS) falls below the grading scale of the five-point benchmark is deemed not necessary a risk factor associated with PPP MHPs and thereby expunged from the second round of the Delphi Survey. The interview was subsequently applied to the respondents to substantiate the risk factors that are peculiar to PPP-procured mass housing in the study area. Findings The findings show that risk factors such as maintenance frequent than expected, life of facility shorter than anticipated and maintenance cost higher than expected fall below 5.0 benchmark with MIS of 4.64 and 4.55 indicating that the risk factors are not peculiar to PPP mass housing in Nigeria. Research limitations/implications The implication for practise of this research is that these risk factors provide the PPP stakeholders with the comprehensive checklists that can aid in developing PPP risk assessment guidelines in the sector though both partners should be aware of the dynamic nature of risk because new ones might be emerging. Originality/value The authors hereby declare that the research findings are a product of a thorough research conducted in the study area and have not to be submitted or published by another person or publisher and due acknowledgement was made where necessary.

AN EVALUATION OF HOUSING FLEXIBILITY AFTER SEVEN YEARS OF HABITATION: IBA HAMBURG 2013

Flexibility in housing has been used for a long time to meet the changing needs of inhabitants. After a century of vicissitude, flexibility became a means for architects to deal with social changes in the new millennium. The International Building Exhibition (IBA) 2013, which took place in Hamburg, Germany, is an example of how the concept of flexibility is being adopted. Housing, in particular, the post-occupancy phase, has not been studied, despite the urban-level aspects of the IBA Hamburg having been extensively written about. Seven years after its construction, nothing is known about what happened regarding these new approaches. The purpose of this study is to investigate the number of households in the IBA Hamburg housing projects that have used the promoted concept of flexibility, particularly in the “Building Exhibition within the Building Exhibition.” As a result, this article aims to shed light on this issue by presenting data from a field survey regarding whether floor plan flexibility was used, and if so, to what extent and what were the reasons. As a result, the author utilized an administered and self-administered open and closed-ended survey questionnaire research approach to collect necessary data for the execution of this investigation. The survey was conducted in twenty-two apartments, with four residential buildings chosen as a case selection for this investigation. The results of this study revealed that, despite being considered during the initial planning phase, flexibility was not commonly applied in the housing projects of IBA Hamburg 2013. Furthermore, the findings reveal that the extent of use of flexibility in these case studies is closely linked with the occupation status of the inhabitants.