Reliability assessment in detention basin design

A flood detention basin is one of the structural measures used for the mitigation of floods. Its design consists of determining the required flood storage and the dimensions of bottom outlet(s) and overflow spillway. Hydraulic performance of a detention basin is dictated with the achievement of the desired degree of attenuation which is affected by storage and capacities of outlet facilities. In this paper, a reliability based model is presented for the preliminary design of flood detention basins having dual outlets using a static loading-resistance interference. In the analysis, loading and resistance of the system are assumed as the maximum lake elevation and the crest elevation of the embankment, respectively. By examining the relevant statistical information for some existing flood detention basins in Turkey, the lognormal probability density function is observed to represent the randomness of loading and resistance. Use of the model is illustrated on a case study and a set of relationships are derived among reliability, attenuation, safety factor, and return period for various entrance elevations of bottom outlet and length to crest elevation ratios of overflow spillway, With the execution of the model, various alternatives can be compared from hydraulic conformity, economy, and safety viewpoints.


Reliability Based Assessment of Erodible Channel Capacity
Yanmaz, Ali Melih (2003-08-01)
The surface drainage of an irrigation area is concerned with the collection and removal of storm runoff and excess water from irrigation applications. The engineering problem is to determine the shape, crosssectional area and slope of a stable channel. A reliability-based design, which addresses and treats possible uncertainties associated with the design parameters, is of importance as it leads to realistic decision-making. In this paper, a reliability-based assessment of erodible channel capacity based on...
Yaqubi, Noor Ahmad; Zaifoğlu, Hasan; Akıntuğ, Bertuğ; Sustainable Environment and Energy Systems (2022-8)
This study aims to execute a flood management system and examine the appropriate structural measures to protect Dikmen town against the impacts of flooding. At first, hydrologic models using HEC-HMS tools are developed to simulate the rainfall-runoff processes in each of the three main ungauged sub-basins on the upstream side of the town. Next, the discharge hydrographs of the 5th December 2018 flood event are defined in the 2D HEC-RAS model, and the flood inundation maps of the study area are generated. T...
Khoram, Mohammad Khalid; Aydin, Ismail; Department of Civil Engineering (2022-9-02)
Spillways are the safety structures of dams against floods. Various types of spillways having different hydraulic characteristics can be considered with variable geometric dimensions. On the other hand, hydrologic reservoir routing is an important tool in the optimization of dam reservoir operations for the purpose of water supply for various needs and electricity production in hydropower plants. Some spillways have gates to control and regulate the flow and to store an optimal amount of water. Other spillw...
Assessment of different rainfall products in flood simulations
Özkaya, Arzu; Akyürek, Sevda Zuhal; Department of Civil Engineering (2017)
Floods happening due to heavy rainfall are one of the most widespread natural hazards. To predict such events, accurate rainfall products and well calibrated hydrologic models are essential especially in urban settlements for life savings. With the objective of assessing the rain detection potential of rainfall data products, several hourly rainfall datasets are used as forcing inputs in two hydrologic models. Physic based distributed model, WRF-Hydro, and conceptual based lumped model, HEC HMS, are used to...
Effective stress based constitutive modelling and assessment of seismic pile-soil interaction in liquefiable soils
Ünsal Oral, Sevinç; Çetin, Kemal Önder; Department of Civil Engineering (2014)
The assessment of liquefaction-induced deformations of foundation soils located in seismically active regions has been a major concern for geotechnical earthquake engineers. Inspite of the existing efforts, the prediction of these deformations has remained a "soft" area of practice. Inspired by this gap, a new fully coupled, two-dimensional, effective stress-based, nonlinear and simplified constitutive model, referred to as METUSAND, is developed. As a part of the model development efforts, a “C++” subrouti...
Citation Formats
A. M. Yanmaz, “Reliability assessment in detention basin design,” 1998, Accessed: 00, 2020. [Online]. Available: