دانلود رایگان مقاله انگلیسی اهمیت استفاده از بتن غلطکی در تحقیقات اقتصاد فناوری و طراحی سد های کوچک - اشپرینگر 2017

Abstract

In recent years, and under constraints caused by persistent drought, Algeria has launched a new mobilization strategy for surface water resources from small and medium dams. However, by making a review of the studies and achievements of twenty small dams in the west of Algeria, some deficiencies appeared. In addition to reservoir siltation assessment, operation spillways have been the major constraint on the reliability of these types of dams. The objective of this paper is to use the roller compacted concrete (RCC) for small dams’ design for the benefit it offers and its ability to incorporate spillways. The development of this reflection was applied to the Khneg Azir earth dam situated in southwest of Algeria. Its uncontrolled lateral spillway has registered significant damage following the flood of October 2005, amounted, at that time, to more than 100 million Algerian dinars (1 million US Dollars). The present research encompasses a technical and economical comparative analysis concerning multiple criteria dam design types coupled with the conjugation of the spillways. Thus, on the basis of financial estimates calculated for all design types, the variant RCC remains competitive with that of the earth dam’s spillway isolated (Less than 40% of the cost). To assess the mechanical behavior of the foundations for both types of dams, (earth and RCC dams), numerical modeling has been undertaken, according to the comparative analysis of deformations in the foundations. Analysis of deformations showed that the average foundation deformations was between (0.052–0.85) m for earth dam and (0.023–0.373) m for RCC dam. These economical and technical considerations open up important prospects for the use of RCC in the design of small dams.

Conclusion

All hydraulic calculations engaged on the different variants were used to define the geometry elements of spillways. Checking the structural stability of RCC gravity profile against sliding and overturning, led to the stability criteria ensured according to the profile designed for different types of support foundations. The calculations and developed hydraulic checks were used to evaluate of volumes of work completed by their financial estimate, and to establish an economic comparison of different variants analyzed. Thus, on the basis of financial estimates developed for all variants, the RCC dam remains competitive with that of the earth dam with isolated spillway. Numerical modeling has led, according to the deformation analysis in the foundation, to a comparison of the proposed variants. Deformations calculated by modeling resulted in average values between (0.052–0.85) m and (0.023–0.373) m, respectively, for the earth and RCC dams’ variants. Finally, according to the results obtained, the use of RCC for the design of small dams in Algeria is an interesting solution, which will solve the constraints to the design of this type of structures with isolated spillways.