Evaluation of landslide analyzing models in weak rocks—case study: Abnahr damsite,Kohgilouyeh and Booyer Ahamd Province,Iran

The right abutment of Abnahr dam consists of Cretaceous marl and some marly limestone that are highly fractured due to tectonic stresses. Low strength and highly fractured structure of the rocks result in fragmentation during drilling by the rock sampling tools. However, this material is still too strong for conventional soil sampling methods. The types of marl are similar to rock material in natural landscapes but drilled material has soil-like behavior. This paper evaluates the behavior of this material in slope stability problems that concern the right abutment of Abnahr dam in existing conditions. For attaining reliable answers to this problem, several undisturbed samples were provided with assistance of the experienced experts and using specific methods. As these samples were rather soils, they were tested by various soil tests such as three-dimensional tests. Moreover some samples were gathered by hand-operated methods including test pits. In order to gain information about the rock parameters, several rock tests were performed. In the next stage, by use of the results of laboratory tests and field observations, slope stability analyses were performed on several models of right abutment of the dam. Lastly, a comparison between different analysis methods of the performed models on right abutment under virtual loads led to important conclusions.     

Mixed structures—A case study of a portal frame in concrete and timber

The authors explain the rationale behind the design of a 30 m span timber trussed portal frame with concrete columns. The design decisions as well as design methods are explained. They show that by using timber to its best advantage, a lightweight, cost-effective structure can be obtained.     

Susceptibility assessment of debris flows using the analytic hierarchy process method——A case study in Subao river valley,China

Many debris flows have occurred in the areas surrounding the epicenter of the Wenchuan earthquake.Susceptibility assessment of debris flows in this area is especially important for disaster prevention and mitigation. This paper studies one of the worst hit areas, the Subao river valley, and the susceptibility assessment of debris flows is performed based on field surveys and remote sensing interpretation. By investigating the formation conditions of debris flows in the valley, the following assessment factors are selected: mixture density of landslides and rock avalanches, distance to the seismogenic fault, stratum lithology, ground roughness, and hillside angle. The weights of the assessment factors are determined by the analytic hierarchy process(AHP) method. Each of the assessment factors is further divided into five grades. Then, the assessment model is built using the multifactor superposition method to assess the debris flow susceptibility. Based on the assessment results, the Subao river valley is divided into three areas: high susceptibility areas, medium susceptibility areas, and low susceptibility areas. The high susceptibility areas are concentrated in the middle of the valley, accounting for 17.6% of the valley area.The medium susceptibility areas are in the middle and lower reaches, most of which are located on both sides of the high susceptibility areas and account for 45.3% of the valley area. The remainders are classified as low susceptibility areas. The results of the model are in accordance with the actual debris flow events that occurred after the earthquake in the valley, confirming that the proposed model is capable of assessing the debris flow susceptibility. The results can also provide guidance for reconstruction planning and debris flow prevention in the Subao river valley.     

Influence of acid rain on slope instability mechanism—a case study in Sichuan provincial highway,China

Bulletin of Engineering Geology and the Environment - Acid rain has important influences on the physical and mechanical properties of rock as a result of mineral conversion and dissolution of...     

Dynamic behaviour of a modern bell tower — A case study

The present study evaluates the dynamic behaviour of a modern concrete bell tower built in 1994. The structure has an unusual geometrical shape, with a wall 20 m high and 0.40 m thick. The tower’s dynamic interaction with the forces caused by the bells swinging becomes clearly evident even without using instrumentation. In 1998 the structure was strengthened by means of a three-dimensional steel truss, but the dynamic problem still exists after the strengthening. Consequently, the authors conducted a study to assess the scale and cause of the problem which consisted of an experimental and numerical study on the tower. This paper highlights the dynamic problem that bells can cause to slender bell towers and recommendations are given to help minimise this fact.     

Solid waste management in the tropics — a case study of the Nigerian urban environment

A study of solid municipal waste management in five conjested cities in the Eastern states of Nigeria was carried out. Random sampling of waste piles show that the percentage composition by weight of garbage range between 32–56%, rubbish 8–30%, Ash/Dust 15–35% and Miscellaneous wastes 4–12%. The wastes were of peculiar nature but varied only in quantity with each city. Interviews and questionnaire reports show that the Environmental Protection Agencies are still in an infant stage of operation and require improved funding by government and also private sector participation. A public enlightenment campaigns is recommended for proper education of the public on modern ways of garbage disposal. Poor composting of solid wastes in landfills located near highways is discouraged. Solid waste recycling and reclamation using an advanced tropical composter equipped with solar collectors or a continous flow digester are recommended.     

The effect of air temperature on labour productivity in call centres—a case study

The aim of this paper was to investigate the effect of air temperature on labour productivity in telecommunication offices. The study was conducted as a case study in two call centres because the work in the call centres can be considered to represent typical activities in the telecommunication industry. The study design consisted of an observational approach and an intervention approach. In Call Centre I, the productivity between two zones with temperature difference was compared. In Call Centre II, the intervention was conducted by installing cooling units to lower high temperature in the summer. Productivity was monitored both before and after the intervention, and it was measured as labour productivity by monitoring the number of telephone calls divided by the active work time. The indoor climate of both call centres was determined by measuring thermal climate and concentrations of relevant air pollutants as well as the acoustical environment and lighting levels. The study shows that productivity may fall by 5–7% at the elevated indoor temperatures.     

The justification of planning solutions in ecological housing ‐ a case study of Viikki in Helsinki

Ecology and sustainability have produced new challenges to traditional argumentation in urban planning. In addition to the rhetorical approach informed by Perelman's ‘new rhetoric’, the recent changes can be analysed by using more traditional philosophical argumentation critique, which is also in line with recent developments in argumentation theory. The state of the art in planning is analysed in this article through a case study of an architectural competition for ‘ecological housing’ held in Helsinki in 1995. The analysis illustrates the way that environmentalism produces new discursive means of justification, but not necessarily new types of urban planning.     

Determination of the maximum allowable gas pressure for an underground gas storage salt cavern——A case study of Jintan,China

Increasing the allowable gas pressure of underground gas storage (UGS) is one of the most effective methods to increase its working gas capacity. In this context, hydraulic fracturing tests are implemented on the target formation for the UGS construction of Jintan salt caverns, China, in order to obtain the minimum principal in situ stress and the fracture breakdown pressure. Based on the test results, the maximum allowable gas pressure of the Jintan UGS salt cavern is calibrated. To determine the maximum allowable gas pressure, KING-1 and KING-2 caverns are used as examples. A three-dimensional (3D) geomechanical model is established based on the sonar data of the two caverns with respect to the features of the target formation. New criteria for evaluating gas penetration failure and gas seepage are proposed. Results show that the maximum allowable gas pressure of the Jintan UGS salt cavern can be increased from 17 MPa to 18 MPa (i.e. a gradient of about 18 kPa/m at the casing shoe depth). Based on numerical results, a field test with increasing maximum gas pressure to 18 MPa has been carried out in KING-1 cavern. Microseismic monitoring has been conducted during the test to evaluate the safety of the rock mass around the cavern. Field monitoring data show that KING-1 cavern is safe globally when the maximum gas pressure is increased from 17 MPa to 18 MPa. This shows that the geomechanical model and criteria proposed in this context for evaluating the maximum allowable gas pressure are reliable.     

Tracer gas dispersion in ducts—study of a new compact device using arrays of sonic micro jets

One of the most feasible ways to measure duct airflows is by tracer gas techniques, especially for complex situations when the duct lengths are short as well as their access, which makes extremely difficult or impossible other methods to be implemented. One problem associated with the implementation of tracer gas technique when the ducts lengths are short is due to the impossibility of achieving complete mixing of the tracer with airflow and its sampling. In this work, the development of a new device for the injection of tracer gas in ducts is discussed as well as a new tracer-sampling device. The developed injection device has a compact tubular shape, with magnetic fixation to be easy to apply in duct walls. An array of sonic micro jets in counter current direction, with the possibility of angular movement according to its main axle ensures a complete mixing of the tracer in very short distances. The tracer-sampling device, with a very effective integration function, feeds the sampling system for analysis. Both devices were tested in a wind tunnel of approximately 21 m total length. The tests distances between injection and integration device considered were: X/Dh = 22; X/Dh = 4; X/Dh = 2; and X/Dh = 1. For very short distances of X/Dh = 2 and X/Dh = 1, semi-empirical expressions were needed. A good reproducibility of airflow rate values was obtained. These preliminary tests showed that the practical implementation of tracer gas techniques in HVAC systems for measuring airflow rates with a very short mixing distance is possible with the devices developed.     

Impacts of climate change on urban drainage systems – a case study in Fredrikstad,Norway

Norway has frequently encountered flood damage in urban areas during recent years. In this paper the authors, taking Veumdalen catchment in Fredrikstad as an example, simulated the possible consequences in the sewer system, in the present, predicted and artificial climate scenarios. Indicators that describe (1) surface flooding, (2) surcharging sewers, (3) basement flooding and (4) combined sewer overflow (CSO) are defined to represent the adverse effects of climate change. It is concluded from the annual-based simulation that the total volume of water spilling from the flooding manholes will increase 2–4-times the increase in precipitation, and the total CSO will increase 1.5–3-times as much as the increase in precipitation. The simulation results also show that the number of flooding manholes and number of surcharging sewers may change dramatically and irregularly with a slight change of precipitation, and vary with events and durations.     

Stakeholders’ perception of residential density: a case study of Adelaide, Australia

‘Residential density’ is a frequently used concept often applied in planning practice. The notion of density policy is well understood; however, it is perceived, and by extension applied, differently across the world. Despite the increased focus and awareness of housing density, there appears to be little coherence or consensus within the planning and development sector, political circles and the general community about what it is, how it should be applied, and whether or not it is a positive or negative feature. Therefore, the aim of this paper is to identify stakeholders’ understanding of density. In order to achieve this, a case study approach was adopted in order to know the various stakeholders’ awareness and comprehension of density, and to that end, Adelaide, the capital city of South Australia, was selected as a case study city for this purpose. The research demonstrated that the stakeholders’ perception of density is strongly influenced by the built form of residential areas (for example, public image) rather than that of measurement or scale, even though there is no direct relationship between built form and density.     

Long-term deflection of cracked composite beams with nonlinear partial shear interaction — A study using neural networks

A new study of the short- and long-term deflections of simply-supported composite beams using finite element analysis and artificial neural networks (ANNs) is presented. In this study, two ANN models are developed and trained using the results of a finite element model developed by the authors in a companion paper. The finite element model accounted for the nonlinear load–slip relationship of shear connectors as well as the creep, shrinkage, and cracking of concrete slabs. The effects of creep and shrinkage of the concrete slab are considered only for non-cracked concrete. A large database representing a wide range of different design parameters was constructed for the purpose of training and verifying the two ANN models. It was found that the two ANN models were capable of predicting deflections of composite beams not used as part of the training process. The ANN models were then used to evaluate the effects of non-geometric design variables on the short- and long-term deflections of simply-supported composite beams. Finally, the short- and long-term deflections computed based on the approaches given in the AISC specification and Eurocode 4 were assessed using the results of the finite element model. It was found that the AISC approach underestimates short-term deflections and overestimate long-term deflections when compared with the results of the finite element method.     

The study of power mechanisms—An interactive and generative approach to a case study of Swedish urban renewal

This article demonstrates a methodological approach to the study of power mechanisms. Power is analysed in the interaction between three dimensions: (1) decision‐making, (2) non‐decision‐making, and (3) power as influence on consciousness; and three levels: (1) the subject‐subject level, (2) the institutional practices, and (3) the more general structural and cultural conditions. The approach is applied in an intensive process‐oriented case study of Swedish urban renewal. The study demonstrates the accumulativeness of power and powerlessness, and how power mechanisms reinforce but also neutralise one another. How the mechanisms are expressed depends on the specific spatial, social and temporal context in which they operate. The methodological implication of this is that a process‐oriented approach is necessary. The study also shows the importance of incorporating an intermediate level between structure and action into the analysis of power.     

Prediction and prevention of rockburst in metal mines——A case study of Sanshandao gold mine

Rockburst is a kind of artificial earthquake induced by human activities,such as mining excavations.The mechanism of rockburst induced by mining disturbance is revealed in terms of energy in this context.For understanding the rockburst mechanism,two necessary conditions for the occurrence of rockburst are presented:(1)the rock mass has the capability to store huge amount of energy and possesses a strong bumping-prone characteristic when damaged;and(2)the geological conditions in the mining area have favorable geo-stress environments that can form high-stress concentration area and accumulate huge energy.These two conditions are also the basic criteria for prediction of rockburst.In view of energy analysis,it is observed that artificial and natural earthquakes have similar regularities in many aspects,such as the relationship between the energy value and burst magnitude.By using the relationship between energy and magnitude of natural earthquake,rockburst is predicted by disturbance energy analysis.A practical example is illustrated using the above-mentioned theorem and technique to predict rockburst in a gold mine in China.Finally,the prevention and control techniques of rockburst are also provided based on the knowledge of the rockburst mechanism.     

Evaluating the local socio-economic impact of redevelopments using shift-share analysis: a case study of destination redevelopments in Las Vegas (1990–2010)

Monitoring neighbourhood change associated with a redevelopment is important for policy-makers, business leaders and residents. It helps evaluate public policy and changes in the needs of residents and businesses. However, using raw data (e.g. census data) to track such changes can be problematic. It does not allow one to distinguish between trends attributable to macro- and micro-scale processes. This paper demonstrates how a novel neighbourhood-level, GIS-based spatial approach using shift-share analysis can help resolve this issue. To illustrate its utility, this technique is used to examine the local socio-economic impact of destination redevelopments in Las Vegas between 1990 and 2010.     

What will drive household adoption of smart energy? Insights from a consumer acceptance study in Germany

Although smart energy technologies (SETs) can fulfill multiple tasks in increasingly decarbonized and digitalized energy systems, market diffusion is still limited. This study investigates which beliefs influence consumers’ intention to adopt two smart-energy offerings, whether the rapid growth of the smart home market will now drive SET adoption, and if consumer-driven diffusion will lead to sustainability potentials being realized. Building on UTAUT2, a new theoretical model is proposed, and a consumer acceptance survey was conducted in Germany (n = 700). Results indicate that a growing smart home market will not increase SET adoption and that “adjustable green defaults” should be introduced.     

Analysis of Indian residences in terms of energy efficiency through energy education – a case study of Mumbai megacity

The portion of today's and future's world iniquities can be jettisoned if certain targeted innovations and adapted technology are introduced in the residential utilities system. One of these iniquities is energy spendthrift with all its negative consequences for the earth (e.g. depletion of finite energy sources and the subsequent climate change). This paper describes the results of an energy-thrift information and education project taking place in different residents of Mumbai city, India, which records more than 500 residences' routine energy-related behaviour and proves that this behaviour changes to a more energy-efficient one after the propagation of relevant information and the participation into the energy education projects. Namely, response percentages indicating the energy-efficient behaviour increased after project participation, while the ones indicating an energy-squandering behaviour decreased. The Wilcoxon signed rank test was statistically significant in all energy behaviour questions.