Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.12188/8521
Title: Static analysis of concrete dams by modeling of the structural joints
Authors: Stevcho Mitovski
Keywords: concrete arch dam, experimental testing, finite element method, numerical model, contact elements, stress-deformation state, interface, technical monitoring, comparation.
Issue Date: 24-Jul-2015
Publisher: Ss Cyril and Methodius University, Civil Engineering Faculty – Skopje
Journal: Scientific Journal of Civil Engineering (ISSN-1857-839X), Volume 6, Issue 2, 2017
Series/Report no.: Decision for carried out public defense of doctoral thesis;02/2 425-6 from 24.07.2015
Conference: SMAR2015 – Third Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures, Antalya, Turkey, September, 2015
WMHE2015 14th International Symposium on Water management and Hydraulic Engineering, Brno, Czech Republic, September, 2015
4th Congress on dams, Struga, September, 2017.
Abstract: The system da with reservoir lines up in structures with highest potential hazard for the environment. The prediction of the dam’s behavior during construction, first filling and service period is of primary importance in design stage of such complex structures and assessment of their stability. The stability analysis includes understanding of stress – deformation state in the dam body, as well and the interaction of the dam and the foundation. In the doctoral dissertation is presented advanced approach on numerical analysis of the stress – deformation state of concrete arch dam, based on the finite element method. The research within the dissertation are divided in three parts: (1) conveying of experimental laboratorial testing for determination of the strength parameters at contact on materials with different deformable properties (concrete – rock foundation and concrete - grouting mass); (2) numerical analysis of concrete arch dam and (3) comparation of the output results from the numerical analysis with monitoring data of the dam. The first part of the dissertation comprises series of experimental laboratorial testing of the contact concrete – grouting mass, carried out by Hoek’s apparatus, for de¬fining of the strength parameters of the contact presented by dependences tangential stress – displacement (σ-τ) and normal stress – tangential stress (σ–τ). Beside the carried out experimental testing, in the dissertation are also used results from already conducted terrain testing, by using Hook’s apparatus and by method of block – stamp (pressure application) , that determine the behavior of the contact concrete – rock foundation. On base of the obtained results from the conveyed testing, the input parameters for the interface elements, applied for simulation of the interaction of contact surfaces at materials with different deformable parameters within the numerical model, are adopted. The second part of the dissertation includes execution of spatial (three-dimensional) numerical analysis of concrete arch dam. For such purpose are prepared two numerical models: continuous model M1 (in which are modeled the dam and the rock foundation) and discontinuous model M2 (beside the dam and the rock foundation, within the model are included and the interaction zones concrete – rock foundation and concrete – grouting mass, by means of interface elements). The finite element method has been applied for performing of the numerical analysis, by software support of the program SOFiSTiK, which enables modeling of the structure and the foundation, simulation of the initial state, stage construction, reservoir filling and also simulation of the behavior of the contact of materials with different properties. For the materials in composition of the rock foundation is applied linear constitutive law, while the constitutive law for the concrete is adopted by Eurocode 2. Within the performed numerical experiment, the period after dam construction and reservoir first filling has been analyzed apropos following loading states are considered: (a) state after dam construction, (b) state upon primary grouting (only in case of numerical model M2), (c) state at beginning of reservoir filling and (d) state at full reservoir. By the numerical analysis is determined the distribution of the displacements and the stresses for the various loading conditions of the dam. In the third part of the dissertation the output results of the numerical analysis are compared with measured data from dam monitoring. The calculated and measured values show agreement, by what is obtained full picture for the dam behavior for the state after construction and at reservoir first filling. Such comparation also gives insight in the accuracy and precision of the monitoring instruments (the process of calibration of the model as well for the instruments is continuous process). The obtained data and acknowledgments from the dam monitoring during service period, will be used to update the numerical analysis that will provide model with high reliability, in order to follow the long-term behavior of the dam.
URI: http://hdl.handle.net/20.500.12188/8521
Appears in Collections:Faculty of Civil Engineering: PhD Theses

Show full item record

Page view(s)

118
checked on Mar 28, 2024

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.