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Abstract. Flood protection is one of the practical methods in damage reduction. Although it not possible to be completely protected from flood disaster but major part of damages can be reduced by mitigation plans. In this paper, the optimum flood mitigation master plan is determined by economic evaluation in trading off between the construction costs and expected value of damage reduction as the benefits. Size of the certain mitigation alternative is also be obtained by risk analysis by accepting possibility of flood overtopping. Different flood mitigation alternatives are investigated from various aspects in the Dez and Karun river floodplain areas as a case study in south west of IRAN. The results show that detention dam and flood diversion are the best alternatives of flood mitigation methods as well as enforcing the flood control purpose of upstream multipurpose reservoirs. Dyke and levees are not mostly justifiable because of negative impact on down stream by enhancing routed flood peak discharge magnitude and flood damages as well.

The purpose of the present study was to investigate the effect of cellular structure on the impact strength of polypropylene/polyolefin elastomers blend foams produced by the continuous extrusion process. To create different cell sizes, two chemical blowing agents were employed: azodicarbonamide and sodium bicarbonate. Sodium bicarbonate created foams with bigger cell size and cell wall thickness than azodicarbonamide. The impact strength of the neat and blend foams were studied and correlated to the foam properties and structure. It was observed that the impact strength of blend foams was directly related to the concentration of polyolefin elastomers (POE). Increasing POE by up to 30 wt% increased the foam impact strength by more than 400%. On the other hand, Increasing POE content caused the cell size and cell wall thickness to be reduced. Moreover, an attempt has been made to establish a relationship between the impact strength and cellular structural parameters. It was found that in the blend foams with higher cell wall thickness the rough fracture of the cell walls was intensified and in turn, the impact strength of the foams improved further.

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Climate change can cause serious problems for future hydropower plant projects and make them less economically justified. Changing precipitation patterns, rising temperatures, and abrupt snow melting affect river stream patterns and hydropower generation. Thus, study of climate change impacts during the useful life of a hydropower dam is essential and its outcome should be considered in assessing long-term dam feasibility. The aim of this research is to evaluate the impacts of climate change on future hydropower generation in the Karun-III dam located in the southwest region of Iran in two future tri-decadal periods: near (2020–2049) and far (2070–2099). Had-CM3 general circulation model predictions under A2 and B2 SRES scenarios were applied, and downscaled by a statistical downscaling model (SDSM). An artificial neural network (ANN) and HEC-ResSim reservoir model respectively simulated the rainfall–runoff process and hydropower generation. The projections showed that the Karun-III dam catchment under the two scenarios will generally become warmer and wetter with a slightly larger increase in annual precipitation in the near than the far future. Runoff followed the precipitation trend by increasing in both periods. The runoff peak also switched from April to March in both scenarios, due to higher winter precipitation, and earlier snowmelt, which was caused by temperature rise. According to both scenarios, hydropower generation increased more in the near future than in the far future. Annual average power generation increased gradually by 26.7–40.5% under A2 and by 17.4–29.3% under B2 in 2020–2049. In the far period, average power generation increased by 1.8–8.7% in A2 and by 10.5–22% under B2. In the near future, A2 showed energy deduction in the months of June and July, while B2 revealed a decrease in the months of April and June. Additionally, projections in the 2070–2099 under A2 exhibited energy reduction in the months of March through July, while B2 revealed a decrease in April through July. The framework utilized in this study can be exploited to analyze the susceptibility of hydropower production in the long term.

Karun River Basin in south-west of Iran has accommodated a large number of hydro projects including reservoirs, hydropower plants, water convey systems, and irrigation networks. Recent extreme floods of the basin have resulted in damage to the vulnerable flood plain areas and under-construction dam sites. Structural and non-structural approach was pursued to reduce the vulnerability of the region after extreme floods of 2005 and 2006. The paper describes the historical floods and the solutions that were recently implemented in the basin. Resistant cofferdams along with early flood forecasting system (EFFS) and emergency action plan (EAP) have been identified as adoptive short-term solutions. The EFFS incorporates a regional numerical weather forecast system, rainfall-run-off models, a reservoir flood control simulation model, flood routing, and two-dimensional inundation models. Depending on the location of the sites, maximum lead time of forecast is 4-5 days, which is sufficient to evacuate the area and damage centres. An EAP was made for dam break and extreme flood events including maps of hazardous zones and access maps to safe areas in the damage centres, mainly in the large cities of the flood plain area.

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Concrete is one of the environmental pollutants. Cement as a main part of the concrete is one of the largest greenhouse emitters. So, searching for a solution to reduce negative environmental impacts of concrete production can be valuable (Pacheco-Pacheco-Torgal, 2014). Ceramic tile and sanitary ware are among the most commonly used materials in construction. World production of ceramic tiles in 2016 was about 13 billion square meters . The amount of waste in the different production stages of the ceramic industry ranges from 3 to 7 percent of daily production (Meyer, 2009). The nature of construction industry, especially the concrete industry, is such that ceramic wastes can be used safely with no need for dramatic change in production and application process. On one hand, the cost of deposition of ceramic waste in landfill will be saved and, on the other, raw materials and natural resources will be replaced, thus saving energy and protecting the environment.