Akademik Veri Yönetim Sistemi
IWA 4th Regional Conference on Diffuse Pollution and Eutrophication, İstanbul, Türkiye, 24 - 28 Ekim 2022, ss.454-459, (Tam Metin Bildiri)
Dams, essential hydraulic structures in water planning and management, have several benefits for a society like providing irrigation, electricity generation, flood control, water supply and recreation. However, many dams have almost reached or exceeded the estimated construction life; thus they risk structure stability. Even though it is comparatively rare, dam failures resulting from flood wave propagation can cause immense damages. Although dams are trustworthy, many disasters that occurred in the past show that a dam can fail in different ways, such as piping or overtopping. Since the collapse of a dam will directly affect most people’s lives, analyzing the dam failure and determining the flood area caused by the failure becomes significant. Two-dimensional (2D) numerical simulation proved to be an effective tool for understanding flood events caused by dam failure. HEC-RAS 2D, one of the most popular hydraulic models, is implemented to estimate the breaching parameters and flow conditions. In this study, the downstream of a consecutive dam system, consisting of Elmalı 2 concrete-buttress dam, which is unique among dam failure studies located upstream and Elmalı 1 earth-fill gravity dam located downstream of the watershed is selected as the study area. Since heavy traffic highway and densely residential regions are located just around the downstream of the consecutive dam system, this vulnerable study area is preferred. The study aims to evaluate the dam failure analysis of Elmalı 2 dam with more water holding capacity under different scenarios. Moreover, the inundation regions are also evaluated visually, and areal differences are analyzed comparatively. The dam failure simulation scenarios are examined for three significant criteria: breach formation time (BFT), the number of failed buttresses for Elmalı 2 and reservoir volume rate of Elmalı 1 (RVR). Therefore, peak water depth (Hp), peak flow rate (Qp), peak velocity (Vp) and time to reach the peak (tp) are discussed for the study area by comparing the scenarios. The results show that breach formation time and the number of failed buttresses effectively affect the peak flow rate, peak velocity, peak depth and time to reach the peak. On the other hand, it has been observed that there is no severe effect of the reservoir volume rate of Elmalı 1 in the consecutive dam system. Hence, the effects of these criteria on the susceptible city area located downstream of the possible failure of Elmalı 2 is presented.