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Dams require high-volume of construction materials and operations over the life cycle. This paper aims to select a proper type of dam structure that can significantly contribute to the sustainability of dam projects.

This research proposes a complementary fuel consumption and carbon dioxide (CO₂) emission assessment method for the alternate dam structure types to assist decision-makers in selecting sustainable choices. Related equations are developed for two common earthen and rock-fill dam structures types in Iran. These equations are then successfully applied to two real dam project cases where the significance of the achieved results are assessed and discussed.

The achieved results of the case studies demonstrate a high deviation of up to 41.3% in CO₂ emissions comparing alternate dam structure scenarios of earthen and rock-fill dam structures. This high deviation represents an important potential for CO₂ emission reduction considering the high volume of the emission in large dam projects.

The life cycle emission assessment of the alternate dam structures, proposed in this research as a novel complementary factor, can be used in the decision-making process of dam projects. The results in this research identify high potential sustainability improvement of dam projects as a result of the proposed method.

Drought and salinity intrusion aggravated by climate change threaten agricultural livelihoods in Viet Nan's Mekong Delta. In response, authorities have built water management infrastructure for irrigation and salinity protection. This study assessed the impact of one such project, the Ba Lai dam in Ben Tre province, on the livelihoods of aquaculture farmers.

This study uses the Sustainable Livelihoods Framework to assess the impact of the Ba Lai dam on the livelihood capitals of 18 farming households in four communes, located both upstream and downstream of the dam.

The authors find that, apart from some positive effects, the dam has also brought negative environmental consequences, such as increased water pollution. The authors also find that farmers have responded to the changes by adapting their livelihood practices.

The samples were relatively small, encompassing four communes in Ben Tre province. On the other hand, this case study is instructive to the many ongoing infrastructure projects in the Vietnamese Mekong Delta.

The project have caused an increase in water-related social conflict.

The case of the Ba Lai dam provides a cautionary example for infrastructure-based water management plans, both in Viet Nam and more broadly. The study suggests the need to strengthen community participation and prioritize impacts of farmers' capital assets when constructing water management infrastructure for climate change adaptation.

The purpose of this paper is to obtain an insight into the effects of sliding and/or joint opening at the contraction, perimeter and concrete lift joints on the nonlinear seismic response of arch dams.

The seismic behavior of a typical thin double curvature arch dam is studied by a nonlinear finite element program developed by the authors. Joints are modeled with the use of zero thickness interface elements. Various constitutive relationships are implemented to account for sliding and opening along the joints. Effects of joint sliding parameters and foundation rock flexibility are also considered in the analyses.

The findings provide information about dynamic stress distribution through the dam body and stability of the dam as a whole and also the local stability of the most critical concrete blocks in the dam body.

Useful information for designing new arch dams or seismic evaluation of constructed dams.

This paper takes into account the stability of concrete blocks in the dam body as well as stability of the structure as a whole. Except for contraction joints, perimeter and concrete lift joints are also modeled. Practical as well as detailed models of sliding are provided for the analyses. The paper offers practical help to design and dam engineers.

For gravity dams built on foundations with directional joint sets, the seepage in the foundation possesses anisotropic characteristics and may have adverse effects on the foundation stability. A methodology for system reliability analysis of gravity dam foundations considering anisotropic seepage and multiple sliding surfaces is proposed in this paper.

Anisotropic seepages in dam foundations are simulated using finite element method (FEM) with the equivalent continuum model (ECM), and their effect on dam foundation stability is involved by uplift pressures acting on the potential sliding surfaces. The system failure probability of the dam foundation is efficiently estimated using Monte Carlo method (MCM) combined with response surface method (RSM).

The case study shows that it is necessary to consider the possibly adverse effect of anisotropic seepage on foundation stability of gravity dams and the deterministic analysis of the foundation stability may be misleading. The system reliability analysis of the dam foundation is justified, as the uncertainties in shear strength parameters of the foundation rocks and joint sets as well as aperture, connectivity and spacing of the joint sets are quantified and the system effect of the multiple potential sliding surfaces on the foundation reliability is reasonably considered.

(1) A methodology is proposed for efficient system reliability analysis of foundation stability of gravity dams considering anisotropic seepage and multiple sliding surfaces (2) The influence of anisotropic seepage on the stability of gravity dam foundation  is revealed (3) The influence of estimation errors of RSMs on the system reliability assessment of dam foundation is investigated.

The purpose of this study is to develop and verify a methodology for a zoned deformation prediction model for super high arch dams, which is indeed a panel data-based regression model with the hierarchical clustering on principal components.

The hierarchical clustering method is used to highlight the main features of the time series. This method is used to select the typical points of the measured ambient and concrete temperatures as predictors and divide the deformation observation points into groups. Based on this, the panel data of each zone can be established, and its type can be judged using F and Hausman tests successively. Then hydrostatic–temperature–time–season models for zones can be constructed. Through the comparative analyses of the distributions and the fitted coefficients of these zones, the spatial deformation mechanism of a dam can be identified. A super high arch dam is taken as a case study.

According to the measured radial displacements during the initial operation period, the investigated pendulums are divided into four zones. After tests, fixed-effect regression models are established. The comparative analyses show that the dam deformation conforms to the natural condition. The factors such as the unstable temperature field and the nonlinear time-dependent effect have obvious effects on the dam deformation. The results show the efficiency of the proposed methodology in zoning and prediction modeling for deformation of super high arch dams and the potential to mining dam deformation mechanism.

A zoned deformation prediction model for super high arch dams is proposed where hierarchical clustering on principal component method and panel data model are combined.

The purpose of this paper is the analysis of the dissipation of pore water pressures in the core of an earth dam, under the effect of water level fluctuations in the reservoir under operating conditions, taking into account the partial emptying and filling.

The Taksebt Dam, Tizi-Ouzou, Algeria was chosen as a case study, using a two-dimensional transient finite element numerical model. The GeoStudio calculation software is used through the SEEP/W. The latter takes into account the flow in the saturated and unsaturated zone, the formulation of SEEP/W allows the analysis of the dissipation of pore water pressures in the dyke. Starting from the maximum level of the reservoir, at least one cycle of partial emptying-filling was modelled over an eight-year operating period from 2011 to 2019. The input variables were the water level variation curve, material properties and boundary conditions.

It can be concluded that the numerical results obtained from the simulation model on the different points studied, namely, the pore water pressures are satisfactory as long as they are close to those recorded in the field by the pore pressure cells with an average error not exceeding 10% except for some measurements where the error is 20%. When the water level in the reservoir varies, the pore water pressures vary and their behaviour follows these fluctuations. Some points in the dam are affected by negative pore water pressures. No abnormal situations have been detected pore water pressures.

The numerical results of the simulation are analysed and validated against actual pore pressure cell measurements under operating conditions.

Power and politics.

This case is suitable for all levels of students, undergraduate MBA to Executive MBA classes and practitioners. Assignment questions are designed from the perspective of teaching this case to a business student audience.

A raging dispute between Kerala and Tamil Nadu over the 116-year-old Mullaperiyar Dam was in the national spotlight after mild tremors shook nearby areas. The Mullaperiyar Dam was located in Idukki district of Kerala in India. The dam was filled to its maximum permissible level of 136 ft. Tamil Nadu wanted the storage capacity to be increased by raising the dam height from 136 ft (41.5 m) to 142 ft (43 m) as per a 2006 Supreme Court directive to meet the growing irrigation needs of the state. The dam was vital for people living in the drought-prone districts of Theni, Dindigul, Madurai, Sivagangai and Ramanathapuram of Tamil Nadu. It irrigated about 220,000 acres and supplied drinking water to Madurai city and several towns. Kerala on the other hand wants a new dam as it feared that a strong earthquake might damage the existing dam. Chief Minister of Kerala, Oommen Chandy said: “I strongly believe that only a new dam can provide safety to the people of Kerala. We are only concerned about the safety of the people. But, unfortunately, there is a feeling in Tamil Nadu that the situation of panic here is a created one. That is not at all correct”. However, Tamil Nadu Government said the dam was safe as it had undergone periodic repairs during 1980-1994 with Kerala Government's approval. With the Kerala Government screaming loud over the danger that could be caused by the alleged obsolete 116 year old Mullaperiyar Dam on safety grounds of people who live downstream, why is Tamil Nadu defiant on any debate that cites the decommission of the controversial dam? Is the Tamil Nadu Government overlooking the issue for its personal benefits by putting the lives of 3 million people at stake?

The case would fit in a course for power and politics. It would also be appropriate for a modular course on regional development planning.

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Farm dam safety in Australia is being flouted and sustainability of catchments compromised because of the potential and severe consequences of dam failure. Hence, the purpose of this paper is to explore policy issues associated with safety of farm dam water storage through a comparison of developments in two Australian states against an analysis of international benchmarks and to provide an exemplar of best practice.

A strategic review and content analysis is firstly undertaken to establish international dam safety policy benchmarks ranging from minimum to best practice as well as selection guidelines for varying circumstances, and to identify an exemplar best practice model. Longitudinal study over a 12‐year period then provides the basis for case analysis in order to reinforce the established minimum level benchmark and to demonstrate the application of the benchmarked model policy selection guidelines.

Research results show that in Australia, South Australia is lagging international benchmarks for on‐farm dam safety management in a number of ways whilst a second state, Tasmania, provides leadership in this respect. The paper adds to the existing international benchmarking literature by identifying updated international best practice in private/farm dam safety assurance policy whilst establishing and providing longitudinal case study reinforcement for an acceptable minimum level benchmark in this area. The updated policy guidelines presented can be used to determine appropriate dam safety policy for any jurisdiction.

The paper provides an original contribution of analysis, establishment and case study validation of international benchmarks and guidelines on developing appropriate dam safety management and assurance policy for varying jurisdictional circumstances. In addition, it provides an updated exemplar of how policy benchmarks can go towards addressing cumulative threats of smaller dams in catchments not previously addressed.

Assembly Sequence Planning integrating assembly Resources (ASPR) is a trend in industry. Because of the introduction of resource, the complexity of ASPR for complex product increases drastically; besides, the dynamic property of resource and the co‐existence of assembly sequence and disassembly sequence (ASDS) make the problems in ASPR more difficult. The dynamic assembly model (DAM) based on polychromatic sets (PS) theory was proposed to address these issues.

First, a strategy was presented to simplify ASPR, taking advantage of assembly sequence generated in the phase of assembly design which considers no resource. Secondly, the concept of DAM was discussed, and some principles/criteria for DAM modeling were generalized from experience. Then, the DAM was modeled by formalizing its incidence relations as PS matrix, and refined based on the formalized criteria, which were expressed as PS locating and collision relation models. Finally, an application case was studied to demonstrate the effectiveness of the method.

The approach could reduce the complexity of ASPR significantly, and was able to identify dynamic resource, model DAM and handle the co‐existence of ASDS effectively.

The method may change the manual pattern of ASPR in simulation environment, and become a potential tool to change the pattern of traditional ASP which comes to work from scratch, by utilizing the upstream information of product design.

Different from traditional assembly model, DAM was a local model which consists of partial components of product and resource, and the DAM‐based ASPR approach would make the computational complexity of product assembly become more linear than exponential.

This study is an attempt to estimate the influence of the presence of cavities on the stability of slopes in earth dams under rapid drawdown conditions. The purpose of this paper is to study the influence of different factors, such as the diameter and location of cavities, in addition to their existence effects.

A series of finite element simulation models were developed using PLAXIS 2D finite element software to analyse the stability of slopes in earth dams while considering various effects from cavities in the subsoil under rapid drawdown conditions.

The results indicated that the presence of cavities and an increase in the diameter of cavities decreased the stability of the upstream face dramatically for all examined locations in a horizontal direction; however, this effect was less on the downstream side. The results also showed that variations in the location of cavities in the horizontal direction have a greater effect on the stability than those in the vertical direction. The results revealed that increasing shear strength parameters of embankment does not reduce the influence of cavities on stability when those cavities are in critical locations.

A numerical model has been developed to simulate the effects of cavities on the stability of slopes in water-retaining structures/earth dams. The stability of earth dam slopes on upstream and downstream sides under rapid drawdown conditions considering various cavity effects, including their existence, diameter and location, were numerically analysed.