Beware fast tracking high rise building

Currently, employers tend to fast rack works where construction can begin while design is still incomplete following three main phases of procurement. This session details a case study of a fast track overseas super high rise building, where an Australian firm acted as a technical expert to provide a detailed report on the failure of the shoring system, while construction of five basements had just started next to a marina. The lessons learnt from the case study are summarized with recommendations to have better practice of the fast track method in complex high rise buildings.

Evaluation of numerical procedures to determine seismic response of structures under influence of soil-structure interaction

In this study, the accuracy and reliability of fully nonlinear method against equivalent linear method for dynamic analysis of soil-structure interaction is investigated comparing the predicted results of both numerical procedures with the results of experimental shaking table tests. An enhanced numerical soil-structure model has been developed which treats the behaviour of the soil and the structure with equal rigour. The soil-structural model comprises a 15 storey structural model resting on a soft soil inside a laminar soil container. The structural model was analysed under three different conditions: (i) fixed base model performing conventional time history dynamic analysis, (ii) flexible base model (considering full soil-structure interaction) conducting equivalent linear dynamic analysis, and (iii) flexible base model performing fully nonlinear dynamic analysis. The results of the above mentioned three cases in terms of lateral storey deflections and inter-storey drifts are determined and compared with the experimental results of shaking table tests. Comparing the experimental results with the numerical analysis predictions, it is noted that equivalent linear method of dynamic analysis underestimates the inelastic seismic response of mid-rise moment resisting building frames resting on soft soils in comparison to the fully nonlinear dynamic analysis method. Thus, inelastic design procedure, using equivalent linear method, cannot adequately guarantee the structural safety for mid-rise building frames resting on soft soils. However, results obtained from the fully nonlinear method of analysis fit the experimental results reasonably well. Therefore, this method is recommended to be used by practicing engineers.

Monitoring the corrosion of concrete reinforcement using control curves

Corrosion testing (half-cell and LPR) was carried out on a number reinforced concrete panels which had been taken from the fascia of a twenty five year old high rise building in Melbourne, Australia. Corrosion, predominantly as a result of carbonation of the concrete, was associated with a limited amount of cracking. A monitoring technique was established in which probe electrodes (reference and counter) were retro-fitted into the concrete. The probe electrode setup was identical for all panels tested. It was found that the corrosion behaviour of all panels tested closely fitted a family of results when the corrosion potential is plotted against the polarisation resistance (Rp). This enabled the development of a so-called 'control curve' relating the corrosion potential to the Rp for all of the panels under investigation. This relationship was also confirmed on laboratory samples, indicating that for a fixed geometry and experimental conditions a relationship between the potential and polarisation resistance of steel can be established for the steel-concrete system. Experimental results will be presented which indicate that for a given monitoring cell geometry, it may be possible to propose criteria for the point at which remediation measures should be considered. The establishment of such a control curve has enabled the development of a powerful monitoring tool for the assessment of a number of proposed corrosion remediation techniques. The actual effect of any corrosion remediation technique becomes clearly apparent via the type and magnitude of deviation of post remediation data from the original (preremediation) control curve.

Urban heat island and its impact on building energy consumption

Urban areas tend to have higher air temperatures than their surroundings as a result of man-made aiterations. This phenomenon is known as the urban heat island (UHI) effect. UHI is considered to he one of the major problems encountered by the human race this century. Solar radiation that is absorbed during the day by buildings is re~emitted after sunset creating high temperatures in urban areas. Also, anthropogenic heat sources such as air conditioners and road traffic add to the rise in temperatures, A number of
studies have indicated that UHI has a significant effect on the energy use of buildings. In mid- and low-latitude cities, heat islands contribute to urban dwellers' summer discomfort and significantly higher air-conditioning loads. This chapter summarizes and reviews the latest research methodologies and findings about the effect of increased temperatures on the energy consumption of buildings. The latest developments in the heat island mitigation strategies are remarkable, However, more attention needs to be
given to the implementation and testing of these strategies in full-scale buildings.

Synthesis and structure of 1,3,5-tris(diorganohydroxysilyl)benzenes. Novel building blocks in supramolecular silanol chemistry

The 1,3,5-tris(diorganohydroxysilyl)benzenes 1,3,5-(HOR₂Si)₃C₆H₃ (TMSB, R = Me; TPSB, R = Ph) have been prepared and fully characterized by X-ray crystallography. The crystal structure of TMSB features pairwise connected layers, in which the molecules are involved in interlayer hydrogen bonding. The supramolecular hydrogen bond motif may be described as a 12-membered ring that adopts a chair conformation. TPSB forms an equimolar inclusion complex with water, which is associated via hydrogen bonding and apparently fills a void in the crystal packing. In this case, the supramolecular hydrogen bond motif may be described as an eight-membered ring. Two of the water molecules are also associated, giving rise to a water dimer entrapped in the silanol matrix. Besides the hydrogen bonds, the crystal structure of the TPSB·H₂O complex reveals intra- and intermolecular C-H··· π stacking of most of the phenyl groups. Electrospray mass spectrometry shows that TPSB undergoes supramolecular complex formation with a variety of N-donors such as 4-(dimethylamino)pyridine, N,N,N',N'-tetramethylethylenediamine, imidazole, 2-(dimethylamino)pyridine, and 2,2'-dipyridylamine.

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Energy efficient envelope design for high-rise apartments

The energy required to create a comfortable living environment in  high-density cities in hot and humid climates usually demands a substantial electricity usage with an associated environmental burden. This paper describes an integrated passive design approach to reduce the cooling requirement for high-rise apartments through an improved building envelope design. The results show that a saving of 31.4% in annual required cooling energy and 36.8% in the peak cooling load for the BASECASE apartment can be achieved with this approach. However, all the passive strategies have marginal effect on latent cooling load, often less than 1%.

Low energy strategies for high-rise apartments in Hong Kong

High-rise apartments provide 90% of the living requirements in Hong Kong. (Lam 1995) The construction material of these buildings is primarily concrete for both external wall and interior partitions with little or no thermal insulation. Due to the hot and humid climatic conditions and expectations of an ever-increasing standard of living, occupants are installing air-conditioning systems into their apartments. This has generated a tremendous electrical demand as well as an environmental (greenhouse gas emission) concern. This paper explores some of the low energy strategies that can be applied to this building typology. The effect of seven energy-saving strategies ranging from thermal insulation to different window systems and shading devices was investigated. The results show that there is the potential to reduce the annual cooling energy consumption and peak cooling load by 40% and 33% respectively.

Closing the gap? Building surveyors in Oceania

Purpose – The Royal Institution of Chartered Surveyors (RICS) has implemented a policy to expand its influence around the world. Quantity or construction surveyors had an established presence and history of working overseas, offering their services particularly in the Middle- and Far-East. Property surveyors found the transition to working in European Union (EU) countries relatively straightforward and numerous UK property consultancies have European, Asian, North American and Oceanic offices. Furthermore UK-based firms establishing partnerships with overseas real estate firms expanded significantly over the past decade. Building surveying (BS) is a different case. Small numbers work in commonwealth countries but it is limited and in many countries professional and academic qualifications are not recognised. This paper aims to consider the extent of the barriers and opportunities facing RICS chartered building surveyors (CBS) in Oceania (taken as Australia, New Zealand, Papua New Guinea and Fiji) and whether the gap is closing.
Design/methodology/approach – A desktop study reviewed the political, economic and sociological issues that affect the employment opportunities and professional services CBS offer throughout the world. Six opportunities and ten barriers were put to the RICS Oceania Building Surveying Faculty to ascertain their perceptions of these barriers and opportunities. No previous study had identified barriers and opportunities in Oceania for the BS and this research adopted a census survey of RICS practitioners currently employed in the region and the results form the most comprehensive picture of the current position.
Findings – Many respondents felt that stronger links and/or mergers with the different Oceania professional property and surveying bodies would open a large field of opportunities to the CBS. Some provided comments on future business opportunities, for example “leaky buildings,”"dilapidations/‘ make good’ work”, and seemed to be in general agreement that, as businesses came to know the benefits of protecting themselves from rogue tenants (and landlords) by using the services of a CBS, then opportunities would continue to rise. The principal barrier is communicating those skills and the value they add.
Research limitations/implications – The limitations that affected this research were time constraints and communicating with surveyors in Oceania, to whom the authors were not permitted direct access. The research methodology methods were, with hindsight, not ideal for the type and range of data that the researchers sought.
Originality/value – The research will be of use to building surveyors and providers of building-surveying education in Oceania.

Constructing a framework for building relationships and trust in project organisations : two case studies of building projects in China

A framework is constructed that can be used to foster trust and build relationships in construction project organizations in China. The research method was based on in-depth study of two building projects in China and data were collected via face-to-face interviews. The results show that as the project progresses, the dominant relationship within each stage deepens. The deepening relationship gives rise to different types of inherent risks such as a partner's self-interest seeking behaviour and opportunistic actions. To counterbalance these risks, trust fostering tools must be employed such as careful selection and effective management of partners. The framework for fostering trust and building relationship developed in the study suggests that (1) relationship deepens from shallow dependence to deep interdependence as the project progresses; (2) different relationships bring about distinct inherent risks; and (3) different trust-fostering tools counterbalance specific inherent risks. This framework could aid in reducing adversarial relationships by suggesting ways to foster trustworthy relationships.

Low energy design strategies for high-rise apartments in Hong Kong

The thesis provides comprehensive computer simulations of energy consumption in typical high-rise apartment buildings in Hong Kong with a focus on the effects of passive design strategies and air conditioning set-points. This research is related to energy efficient development and urbanisation in the tropics.

Height and construction costs of residential high-rise buildings in Shanghai

A widely recognized theme of construction economics suggests that the cost of construction per square meter increases as building height rises. However, over a number of years, research conducted regarding the height and cost issue has established a classic relationship between the two factors which can be represented by a U-shaped curve. This paper describes the study of the height-cost relationship of high-rise residential buildings in Shanghai in terms of the total construction cost and elemental costs while considering the context and commonality of buildings. This research was developed as an extension of the previous work, which examined data for buildings in Hong Kong. Initial findings indicate that the curves illustrating the relationships between height and cost of residential buildings in Shanghai and Hong Kong exhibit different profiles. The dissimilarities indicate that different sets of criteria should be applied in the judgment of height that affects cost in different locations. In terms of elemental costs, the findings suggest that there are differences in the way these costs react to changes in the building height.

Analysis of the cost performance of structural building frames in Australia

The significance of this research is that it is the first comprehensive analysis of cost performance across Australia. It is well known that measuring cost performance is not an easy task; comparisons of building projects on a `like-for-like’ basis are uncommon, and rarely occur in the real world. However, this paper analyses 120 different structural frame models that represent various; structural designs, construction methods, grid spans, and locations.

The research produced price models that were representative of structural frames used in medium-rise non-residential buildings. It is based on pricing a number of standard building frame designs in five Australian cities. The results represent the cost of producing the same building in different locations, using similar building construction techniques. By utilizing a standard model, project variables like building quality, ground conditions and access were eradicated, thereby facilitating an unbiased comparison of cost performance. I addition, the results are an indicator of building productivity based on costs per square metre of various construction types.

This research provides the Australian industry with robust data about the relative cost performance of various structural building frames. In addition, this research has wider implications because the models may also become useful data for the measuring relative cost performance in other countries.

Cost performance of multi-rise structures in Australia

The article discusses the findings of research on the cost performance of structural frames. The analysis conducted is based on a range of designs that are commonly found in 10-storey buildings in Australia. The study explored the best cost solutions for any particular project through generic cost models of steel, concrete, and formwork systems used in commercial buildings. The research concluded that the most important factor in choosing structural building frames would be the unique characteristics of individual projects.

Business strateBusiness strategies under conditions of uncertainty: The rise of mutual life insurers in colonial Australiagies under conditions of uncertainty

The early development of Australian life insurance was marked by the failure of stock companies to successfully establish a market presence. Mutual insurers emerged in the mid-nineteenth century in response to this gap in supply. The underlying rationale behind their establishment differed but the business model adopted proved remarkably successful. Mutual life insurers dominated the market for life insurance for nearly a century. This chapter investigates mutualism as a business strategy that addressed particular problems associated with doing business in a small and underdeveloped economy. Business and social networks were important facilitators of new business. In addition, most mutual life insurers had a social/philanthropic charter and they were able to utilize this to build business. An outcome of this mix was the emergence of a particular type of entrepreneurship that fostered innovative product development and cemented the role of mutual insurers as market leaders.. The Variety, Choice, Governance, and Regulation of Organizational Forms 2.