• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.3
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• pp.155-166
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• 2008

Research dam is consisted of concrete gravity dam that right bank department is built to concrete material, left bank department is composition dam that is consisted of rockfill dam that consist of rockfill material In domestic case, composition dam form of storage of water facilities of about 17,000 does not exist hardly in dam of irrigation water industry drinking water purpose that manage local government or other institution, Even if exist, is real condition that there is total nonexistence administrator fare of facilities, Choose unique dam of domestic multipurpose dam and analyzed conduct special quality of con'c gravity dam and rockfill dam joint part To analyze dynamic conduct special quality of composition dam by analytic method in this research, Do modelling via axis of dam and achieved static(Psuedo-static, modify Psuedo-static) and dynamic analysis, When achieving earthquake response analysis, analyzed seismic response analysis between concrete part and rockfill's part.

• Tunnel and Underground Space
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• v.13 no.4
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• pp.304-315
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• 2003

In this paper, the DDA method with a new hydro-mechanical algorithm is used to study the effect of rock discontinuities on uplift and seepage in concrete gravity dam foundations. This paper presents an alternative method of predicting uplift and seepage at the base of concrete gravity dams. A sensitivity analysis was carried out to study the importance of several parameters on dam stability such as the orientation, spacing, and location of discontinuities. The study shows that joint water flow and adverse geological conditions could result in unusual uplift at the base of concrete gravity dams, well in excess of what is predicted with the classical linear or hi-linear pressure assumption. It is shown that, in general, the DDA program with the hydro-mechanical algorithm can be used as a practical tool in the design of gravity dams built on fractured rock masses.

• Structural Monitoring and Maintenance
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• v.3 no.2
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• pp.129-144
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• 2016

We present a methodology to validate with monitoring data finite element models of existing concrete dams: numerical analyses are performed to assess the structural response under the effects of seasonal loading conditions, represented by hydrostatic pressure on the upstream-downstream dam surfaces and thermal variations as recorded by a thermometers network. We show that the stiffness effect of the rock foundation and the surface degradation of concrete due to aging are crucial aspects to be accounted for a correct interpretation of the real behavior. This work summarizes some general procedures developed by this research group at Politecnico di Milano on traditional static monitoring systems and two significant case studies: a buttress gravity and an arch-gravity dam.

• Earthquakes and Structures
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• v.3 no.3_4
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• pp.457-471
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• 2012

Current code procedures for stress and stability analysis of new and existing concrete-gravity dams are primarily based on conventional methods of analysis. Such methods can be applied in a straightforward manner but there has been evidence that they may be inaccurate or, possibly, not conservative. This paper presents finite element modeling and analysis procedures and makes recommendations for local failure criteria at the dam-rock interface aimed at predicting more accurately the behavior of dams under hydraulic and anchoring loads.

• Computational Structural Engineering
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• v.9 no.4
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• pp.189-198
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• 1996

The fracture behaviour of concrete gravity dam mainly due to uplift pressure acting at the crack face was studied. Triangular type and parabolic type distribution of the uplift pressure including uniform type were first considered in case of calculating stress intensity factor(SIF) by the surface integral method. Second, the directions of crack propagation according to the uplift pressure distribution were pursued by FRANC(FRacture ANalysis Code). Third, critical crack lengths according to the uplift pressure distribution under the overflow depth were calculated. The SIF values obtained from the surface integral method were compared with those by FRANC and relatively good agrements could be obtained between both of them. And it could be seen that the direction of crack propagation in case of triangular pressure distribution was a little benter to the dam base than the one by the uniform type. Maximum critical crack lengths under the overflow depth were obtained at about 2/5-1/2 of the dam height.

• Coupled systems mechanics
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• v.7 no.3
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• pp.353-371
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• 2018

The Wavenumber or more accurately Wavenumber-FD approach was initially introduced for two-dimensional dynamic analysis of concrete gravity dam-reservoir systems. The technique was formulated in the context of pure finite element programming in frequency domain. Later on, a variation of the method was proposed which was referred to as Wavenumber-TD approach suitable for time domain type of analysis. Recently, it is also shown that Wavenumber-FD approach may be applied for three-dimensional dynamic analysis of concrete arch dam-reservoir systems. In the present study, application of its variation (i.e., Wavenumber-TD approach) is investigated for three-dimensional problems. The method is initially described. Subsequently, the response of idealized Morrow Point arch dam-reservoir system is obtained by this method and its special cases (i.e., two other well-known absorbing conditions) for time harmonic excitation in stream direction. All results for various considered cases are compared against the exact response for models with different values of normalized reservoir length and reservoir base/sidewalls absorptive conditions.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.393-399
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• 2005

The purpose of this study is to suggest some references of maintenance and design of concrete gravity dams by analyzing dynamic characteristics in x, y, z directions. It is considered as additional mass, soil interaction for numerical dynamic analysis for gravity concrete dams in Han River basin as some cases. The result shows that the overflow structure can be possibly underestimated for the evaluation of the seismic performance using seismic intensity, modified seismic intensity methods. A much more research is still necessary for the evaluation of comprehensive seismic performance of concrete gravity dam

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.26-33
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• 2005

In this paper, a computational model for nonlinear crack damage analysis of concrete gravity dam-foundation boundary region subjected to earthquake loading is suggested. An enhanced model based on the Lee-Fenves plastic-damage model is used as the inelastic material model for a concrete dam structure and rock foundation. The suggested model is implemented numerically and used for computational earthquake simulation of Koyna dam, which was severly damaged from the strong earthquake in 1967. From the numerical result it is demonstrated that the suggested computational model can realistically represent crack initiation and propagation in the dam-foundation boundary region.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.12 no.3
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• pp.353-362
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• 1999

This study is aimed to obtain the critical crack lengthes of the concrete gravity dam and to investigate variation of the effective stress intensity factors at the crack tips of multiple cracks. Applied loads are dynamic load composed of blast vibration and hydrodynamic pressure which can be considered in case of the blast work at near construction site, in addition to static load composed of hydrostatic pressure, crack pressure, and gravity load of the dam. The critical crack lengthes were calculated according to the crack locations, directions, and magnitudes of blast vibration. Also variation of the effective stress intensity factors with respect to the multiple crack shapes and distances between the crack tips was investigated.

• Structural Engineering and Mechanics
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• v.91 no.2
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• pp.123-133
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• 2024

The assessment of seismic behavior and seismic performance of ageing Sarıyar concrete gravity dam constructed on Sakarya River in Türkiye is the main focus of this paper. For this purpose, the impact of sediment domain, ageing of concrete material under the impact of chemical and mechanical actions, and dam-water-sediment interaction are included in the two-dimensional (2D) finite element (FE) model developed in FORTRAN 90 environment. In the FE model, the dam and age dependent sediment domains are modeled by solid elements, while reservoir domain is modeled by Lagrangian fluid elements. The radiation of reflected waves to the unbounded water domain is modeled by infinite Lagrangian fluid elements, while unbounded sediment domain is modeled by infinite solid elements. The coupled system was assumed to be under the simultaneous impact of Vertical (V) and Horizontal (H) ingredients of 1976 Koyna earthquake and the coupled system was analyzed in Laplace domain by direct method. Due to the deterioration of the concrete, the H and V displacement responses together with the fundamental period of the body, elongate throughout the lifetime and this reduce the seismic safety of the dam. It was deduced that the ageing dam body will not experience major damages under the Koyna earthquake both at the earlier and later ages. Furthermore, at the heel of the dam, the hydrodynamic pressure responses are decreased by rising the sediment domain depth.