Large-scale Civil Engineering Projects Research Articles

“At night they glow red with fire”: tracing the environmental impact of industrialisation in travel accounts of Merthyr Tydfil, 1848–1881

One would be forgiven for overlooking the fact that Cardiff is a city with a waterfront. Large-scale civil engineering projects such as the Cardiff Bay Barrage have obscured the Welsh capital’s rel...

Introducing Typhoid Conjugate Vaccine in South Asia: Lessons From the Surveillance for Enteric Fever in Asia Project.

Enteric fever remains a public health concern in communities lacking sanitation infrastructure to separate sewage from drinking water. To bridge the gap until large-scale civil-engineering projects are implemented in high-burden countries, typhoid conjugate vaccine presents a promising disease-prevention technology. A new typhoid conjugate vaccine was prequalified by the World Health Organization in 2017 and is beginning to be introduced in countries around the world. To help inform vaccine introduction, the Surveillance for Enteric Fever in Asia Project (SEAP) conducts prospective enteric fever surveillance in Bangladesh, Nepal, and Pakistan. This supplement presents findings from Phase II of the study (2016–2019) on burden of disease, clinical presentation, the growing spread of drug-resistant strains, and policy and economic ramifications. These findings are delivered to support policymakers in their deliberations on strategies to introduce typhoid conjugate vaccine as a preventive tool against enteric fever.

Comparison between physical–mechanical properties of mortar made with Portland cement (CEMI) and slag cement (CEMIII) subjected to elevated temperature

The use of blast furnace slag during the manufacture of cement is assumed to mitigate CO2 emissions. Generally, the amount of blast furnace slag in the slag cement (CEMIII) ranges between 36 % and 95 %. Slag cement is suitable for the production of all concrete classes, such as the large-scale civil engineering projects (roads, tunnels, bridges). In the case of tunnels, evaluating the performance of concrete exposed to high temperatures will be of great interest. This paper deals with the mechanical properties of cement pastes and mortars made with an ordinary Portland cement (CEMI) and slag cement (CEMIII) subjected to temperatures up to 650 °C. For this purpose, The test specimens were cured for 90 days and then subjected to four different temperatures (160, 300, 400 and 650 °C) at 1 °C/min. Following the 1 h of thermal load, the specimens were examined once their temperature cooled down to room temperature. Measurements were taken for mass loss, permeability, residual compressive strength and modulus of elasticity for each temperature.The test results demonstrated that permeability increases with temperature, and it follows an exponential type formula for both types of mortar. Where there is more loss of permeability in MIII mortars than in MI mortars.The residual compressive strength of all specimens increased up to 160 °C and decreased with further increase in temperature. This decrease is more significant when the temperature exceeds 400 °C. For all heating temperatures, the samples made from the slag cement (CIII and MIII) show higher residual compressive than those made with Portland cement (CI and MI). Furthermore, it was found that at all exposure temperatures the modulus of elasticity of all samples was more reduced compared to the compressive strength. In conclusion, we can say that when using slag cement, the samples show a good mechanical behavior (compressive strength and modulus of elasticity) at high temperatures and also for permeability.

Valuation of Projects with Stochastic Cash Flows and Intertemporal Correlations: Practical Modeling Guidelines

This paper explores the influence of cash-flow correlations on the behavior of the net present value (NPV) and internal rate of return (IRR) when performing valuations. In general, correlation has a negligible effect on the expected value of both the NPV and IRR. Even in cases of high correlation the IRR distribution departs very little from normality. In cases of moderate to low correlation, very good approximations of the SD of the NPV and IRR can be obtained, assuming that the cash flows are independent. These results, coupled with the simple two-parameter correlation structure investigated, provide a useful framework to perform valuation analysis of large-scale civil engineering projects.

A case study on the feasibility and performance of an UWB-AoA real time location system for resources management of civil construction projects

The application of integrated satellite and modern wireless positioning technologies for ubiquitous real-time resources management in large scale civil engineering projects can greatly optimize the time and cost in the construction process, and is now the trend for modern construction project man- agement. As the outdoor conditions of most civil construction sites are open to sky, satellite position- ing with the popularly used Global Positioning System (GPS) has been proved to be very e‰cient and eective. However, the condition in indoor and underground construction site is very complicated due to the fact that dierent construction activities would be carried out in dierent congested areas, involving heavy construction plant, equipment, pro- fessionals and technical personnel. Nowadays dier- ent emerging technologies such as Wi-Fi and ZigBee can be adopted for position and tracking in indoor environments. Nevertheless, under the very com- plicated construction site conditions these technolo- gies may fail due to movement of human resources and construction plant, variation of metrological conditions, and serious multipath eects of signals. It is considered that Ultra Wide Band (UWB) tech- nology is more suitable for indoor construction site environments. In this paper, a case study on the attempt of integrating GPS with Ubisense Real- time Location System (RTLS) for resources man- agement in an underground railway construction site is discussed. Laboratory and field tests have shown that the RTLS can provide better resources management capability in terms of positioning accuracy and stability than Wi-Fi and ZigBee tech- nologies under complicated construction environ- ments. The test results show that the system can normally achieve better than 15 cm accuracy, and better than 1 m under adverse geometrical site condition. However, the high instrumental set up cost and the requirement for high quality data trans- mission cable for high precision time synchroni- zation between sensors may deter wide application of similar system for resources management in con- struction sites.

Computer-Supported Collaborative Negotiation Methodology

The development of large-scale civil engineering projects requires the collaboration of experts from different specialties. However, conflicts and disputes occur regularly during the entire life cycle of large-scale projects due to the complex structure of organization and the different types of expertise involved. If these disputes or conflicts cannot be resolved or addressed quickly and effectively, the collaborative mode of the participants can be affected, creating a hostile environment in which progress of the project will slow to a halt. Therefore, better methodologies are needed to improve the collaborative process and to create more effective, efficient, and sustainable solutions to conflicts. This paper presents a methodology for facilitating the negotiation of conflicts during the development of large-scale civil engineering projects. Two fundamental theories are used in this methodology: (1) game theory, which is the study of players' actions based on the premise that the decision of any player can affect the payoff of all players; and (2) negotiation theory, which is the study of the interactions between parties, designed to reconcile their differences and produce a settlement. The strong support given by these two theories to negotiators is highlighted in the following observations. First, people need to negotiate because of their conflicting interests. From the negotiator's point of view, expressing the interests of all participants is very important in conflict resolution and can be accomplished by following the principles outlined in negotiation theory. Once the interests have been expressed correctly, the influence of positions or of conflicting interests on the overall negotiation outcome is evaluated using game theory. Based on these two fundamental theories, this paper presents a collaborative negotiation methodology and a computer agent named CONVINCER, which incorporates that methodology to facilitate or mediate the negotiation of conflicts in large-scale civil engineering projects. Hypothetical case studies and resolution processes demonstrate the effectiveness of the CONVINCER agent in conflict resolution. Results of applying the methodology to different scenarios also show that the CONVINCER agent provides efficient, effective, and sustainable solutions, thus improving the conflict resolution paradigm in the A/E/C industry.

The development of aquatic ecology in the Netherlands

The development of the scientific discipline of aquatic ecology in The Netherlands is described. Dutch aquatic ecology originated in the second half of the 19th century, mainly around the Zoological Station of the Netherlands Zoological Society. In 1888 P.P.C. Hoek was appointed fisheries advisor to the government and thus became the first fulltime professional aquatic ecologist of the country. From 1888 into the first half of the 20th century marine ecology slowly developed around the Zoological Station and the Government Institute for Fisheries Research, which originally were housed in the same building at Den Helder. Freshwater ecology, referred to as hydrobiology, had a later start in about 1920. Hydrobiology in The Netherlands included also brackish-water ecology. Hydrobiology was especially important at the University of Amsterdam. After 1950, a period of growth led to the establishment of several new institutes and university departments in which aquatic ecology was practised, as well as to a considerable increase of the staff numbers in existing institutes. In the same period the largely descriptive hydrobiological studies were replaced by causal-analytical, experimental work in aquatic ecology. Another line of research was ecosystem studies modelled after the then current ideas of the International Biological Programme 1966–1976. Environmental considerations stimulated aquatic ecology in The Netherlands again after 1970. After 1980, the field stabilized and at some places even decreased. The success of aquatic ecology in The Netherlands is ascribed to the geographic nature of the country with its variety of waters and its intimate relationships with water, to the fact that aquatic ecology is able to provide answers at the same spatial scale as the questions asked by water quality managers and to the opportunities offered by large-scale civil engineering projects.