Metaheuristic based soil parameter identification in deep excavations

Download
2019
Akgül, Abdülsamed
Attaining accurate ground parameters in the design of cost- efficient underground structures is essential due to the level of complexity and uncertainty in soil- structure interactions and ground conditions. Backcalculation methods have an increasing popularity in the field of geotechnical engineering due to the fact that these methods rely on laboratory and field tests in addition to field monitoring and field information which delivers genuine structure conditions. Therefore, the use of this method provides much more accurate geomechanical parameters of materials in deep excavations when compared to conventional methods. Moreover, acquiring these parameters in a faster method aids in the calibration of the parameters during fast track construction projects. In this study, a finite element based backcalculation is developed through the use of Particle Swarm Optimization algorithm (PSO). The PSO algorithm, which is embedded in the back-analysis platform, acts as an intelligent parameter selection process which provides data for the finite element method. The reaction of the deep excavation structure is attained through two-dimensional finite element analyses. This developed back analysis framework is then tested using the ground deformation data obtained from the deep excavation case study in Ankara/Turkey. The parameters of soil are backcalculated and these parameters are then used for future predictions of deep excavation response. The attainment of the successful results has been observed due to the use of the optimization algorithm and the sensitivity of the measured values. This backcalculation using the PSO algorithm can be used to create more realistic models for the construction of underground structures which share the same properties and ground conditions.

Suggestions

Metaheuristic based backcalculation of rock mass parameters around tunnels
Gedik, Görkem; Pekcan, Onur; Department of Civil Engineering (2018)
Due to uncertainities in the ground conditions and the complexity of soil-structure interactions, the determination of accurate ground parameters, which are not only used in tunnel construction but in the design of all underground structures, have a great significance in having structures that are cost-efficient. Backcalculation methods which rely not only on laborotory and field tests but also on field monitoring and field data provide real structure conditions and therefore it is gaining popularity in geo...
Multicomponent seismic loss estimation on the North Anatolian Fault Zone (Turkey)
Karim Zadeh Naghshineh, Shaghayegh; Askan Gündoğan, Ayşegül; Erberik, Murat Altuğ; Yakut, Ahmet (null; 2015-12-14)
Seismic loss estimation is essential to incorporate seismic risk of structures into an efficient decision-making framework. Evaluation of seismic damage of structures requires a multidisciplinary approach including earthquake source characterization, seismological prediction of earthquake-induced ground motions, prediction of structural responses exposed to ground shaking, and finally estimation of induced damage to structures. As the study region, Erzincan, a city on the eastern part of Turkey is selected ...
Finite element analysis of a deep excavation: a case study
Aktaş Engin, Tuğçe.; Çokça, Erdal; Department of Civil Engineering (2019)
The optimum use of safety and economy in deep excavation design is possible with the selection of the appropriate system, and modelling of the selected system and soil properties properly. Therefore, soil parameters selection has a crucial effect in deep excavation analyses. The realistic estimation of the displacements with the finite element software is only possible by using the realistic deformation modulus values during analyses. However, in stiff clays for which undisturbed sampling is very difficult,...
Probabilistic models for the initiation of seismic soil liquefaction
Çetin, Kemal Önder; Kiureghian, AD; Seed, RB (2002-01-01)
A Bayesian framework for probabilistic assessment of the initiation of seismic soil liquefaction is described, A database, consisting of post-earthquake field observations of soil performance, in conjunction with in situ "index" test results is used for the development of probabilistically-based seismic soil liquefaction initiation correlations. The proposed stochastic model allows full and consistent representation of all relevant uncertainties. including (a) measurement/estimation errors, (b) model imperf...
Determination of soil hydraulic properties using pedotransfer functions in a semi-arid basin, Turkey
TOMBUL, MUSTAFA; Akyürek, Sevda Zuhal; ŞORMAN, ALİ ÜNAL (2004-12-01)
Spatial and temporal variations in soil hydraulic properties such as soil moisture 0(h) and hydraulic conductivity K(theta) or K(h), may affect the performance of hydrological models. Moreover. the cost of determining soil hydraulic properties by field or laboratory methods makes alternative indirect methods desirable. In this paper, various pedotransfer functions (PTFs) arc used to estimate soil hydraulic properties for a small semi-arid basin (Kurukavak) in the north-west of Turkey. The field measurements...
Citation Formats
A. Akgül, “Metaheuristic based soil parameter identification in deep excavations,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Civil Engineering., Middle East Technical University, 2019.