The code automates the prediction and evaluation of cracking in the dam, along the damrock interface, and in the foundation using incremental nonlinear analysis techniques based on the smeared crack approach. Methods of analysis used to design arch and gravity type concrete dams should 1 numbers in brackets refer to items in the bibliography. Modelling and characterizing a concrete gravity dam for. Crack analysis in structural concrete sciencedirect. Generally, they are constructed on a straight axis, but may be slightly curved or angled to accommodate the specific site conditions. Cg dams is a finite element based program written specifically for the stability analysis of concrete gravity dams. The stability of a dam can be analysed in the following steps. A gravity dam depends on its weight to withstand the forces imposed on it. Hydrologic and structural safety evaluation of aged. This starts when contemporary structural analysis methods such as a finite element method were incorporated into.
Methods of analysis used to design arch and gravitytype concrete dams should 1 numbers in brackets refer to items in the bibliography. Earthquake analysis of concrete gravity dams including dam. Structural analysis of concrete dams, spillways, intake towers, outlet works, gates, valves, etc. Source code on the cdrom and most of the manuals are now available through the. For structures consisting of a section of concrete gravity dam within an. Design manual for concrete gravity dams, parts 115 united states. If you need to print pages from this book, we recommend downloading it as a pdf. Seasonal temperature and stress distributions in concrete. Throughout his career, he has authored and coauthored numerous papers on the various aspects of concrete gravity dams. Earthquake engineering software the nisee software library cdrom, a collection of research software developed from the 1960s through the early 1990s, is sold out. The material parameters used in the model to define the mechanical behaviour and the reaction development were calibrated and fixed using the monitoring information available, provided by hydroquebec.
Earthquake analysis of gravity dams including damwater foundation rock interaction. Seismic analyses could be done using either the pseudostatic or a simplified response spectrum method. Most gravity dams have been designed and built during the past century with methods of analysis that are now considered inadequate. The rising water will cause hydrostatic force which will tend the dam to slide horizontally and overturn about its downstream edge or toe. Here you can explore structural dynamics and earthquake engineering books. Types of concrete gravity dams the engineering community. Conventional concrete and roller compacted concrete are both addressed. Damage to the dam initiates during the seismic analysis in the third step. Earthquake analysis and design of concrete dams has progressed from static force methods based on seismic coefficients to modern procedures that are based on the dynamics of damwaterfoundation systems. Gravity dam design united states army corps of engineers.
Numerical modeling of concrete gravity dams youtube. Massive structures such as concrete gravity dams are very important and complex with respect to safety and stability. Pdf design and analysis of concrete gravity dams researchgate. Simplified earthquake analysis of concrete gravity dams journal. Ghd provides services in dams engineering from foundation and seismic assessments through to geotechnical, hydrological, hydraulic, mechanical and structural design, projects demand indepth skills and a coordinated, clientfocused approach.
The performance of dams and hydropower structures during the wenchuan 512 magnitude 8. Welcome to the civilax virtual library, the most comprehensive online civil engineering resource collection in the world. Concrete faced rockfill dams cfrd and rollercompacted concrete rcc gravity dams are the primary choices for dam construction due to the ease and speed of construction. Cgdams is a finite element based program written specifically for the stability analysis of concrete gravity dams. Stability analysis of concrete gravity dam on complicated foundation with multiple slide planes.
Each discussion is composed of two parts, the basic considerations and the criterion statement. This study proposes a methodology for the proper modelling and characterisation of. Earthquake resistant design of concrete gravity dams. Earthquake analysis and design of concrete dams has progressed from static force methods based on seismic coefficients to modern procedures that are based on the dynamics of dam waterfoundation systems. Gravity dams gravity dams criteria for selection of dam site, construction material, forces acting on gravity dam, modes of failure, stability analysis, safety criteria, methods of design, stress analysis and stress contours, galleries, instrumentation, joints, keys, water seals, temperature control in concrete dams, foundation treatment. Particular attention is given to the coupled field thermal structural transient analysis in which all the available monitoring data are implemented. In adopting several different worldwide published dam safety guidelines, a large number of modelling options have been implemented.
Finite element has been widely used in seismic analysis of concrete gravity dams utilizing the most natural method based on the lagrangianeulerian formulation. Heat transfer and structural analysis models of a typical dam foundationreservoir system are developed. Concrete mix design calculation for m20, m25, m30 concrete with. Publisher summary this chapter introduces a book that focuses on the fracture mechanics of structural concrete. It could also be used for research and development on stability of gravity dams.
A finite element method for the dynamic analysis of concrete gravity dams with displacement based formulation for both fluid and structural domains was presented. Gravity dam is constructed of concrete andor masonry andor laidup stone that relies upon its weight for stability. Analysis of linear response the national academies press. A computer program for the earthquake analysis of concrete gravity dams including base sliding report structural engineering, mechanics and materials chai vez, juan w on. However, predicting the performance of concrete dams during earthquakes is one of the most complex and challenging problems in structural dynamics. Height is the vertical dimension from the downstream toe of the dam at its lowest point to the top of the dam. Gravity dam is constructed of concrete andor masonry andor laidup. Mixture proportioning for mass concrete is discussed in aci 211. Design manual for concrete gravity dams, united states. Cavitation effect and local impact phenomena as a result of change of direction of ground motion was studied for pine flat dam, located in kern country. Hydrothermomechanical analysis of an existing gravity. Specimens in the field, annual book of astm stan dards, vol.
Overload and material weakening were taken into account, and a finite difference strength reserve method with partial safety factors based on the reliability method was developed and used to study the antislide stability of a concrete gravity dam on a complicated foundation with multiple slide planes. Design and construction of concrete gravity dams nptel. Chapter 6 concrete dam engineering with examples 1. A twostage procedure was proposed in 1978 for the analysis phase of. Uncertainty quantification and reduction in the structural analysis of existing concrete gravity dams. In recent decades, knowledge of seismology, structural dynamics and earthquake engineering has greatly evolved, leading to the evaluation of existing dams to ensure public safety. Concrete dam engineering 1 0401544 hydraulic structures university of sharjah dept. A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by primarily using the weight of the material alone to resist the horizontal pressure of water pushing against it.
I a simplified analysis procedure in which the response due only to the fundamental vibration mode is estimated directly from the earthquake design spectrum. The purpose of this chapter is to conduct a general comparison of different fracture procedures in terms of nonlinear response and cracking development for concrete structures using 3d seismic analysis of gravity and arch dams. Problem 911 a concrete dam has the profile shown in figure p911. A concrete gravity dam is a massive concrete structure, roughly triangular in shape, and designed so that its weight ensures structural stability against the hydrostatic pressure of the impounded water and other forces that may act on the dam. Dec 20, 2017 concrete faced rockfill dams cfrd and rollercompacted concrete rcc gravity dams are the primary choices for dam construction due to the ease and speed of construction.
Concrete and masonry dams the national academies press. The dams include concrete gravity dams, concrete arch dams single and double curvature, concrete buttress and multiple arch dams seismic and dynamic response analysis natural. Coupled thermalstress finite element analysis has been performed on a fullscale concrete gravity dam to determine the impact of changing the time intervals in concrete placing schedule on the. Centrifuge modeling and analysis of concrete gravity dams. The slide mode of a gravity dam consists of shallow slide along the foundation base and deep slide in the.
Unfortunately, this book cant be printed from the openbook. The behavior of these dams under seismic loads plays an important rule for. Structural safety is evaluated with respect to the main failure modes cracking, concrete crushing and sliding at the damfoundation interface using the monte. The slide mode of a gravity dam consists of shallow slide along the foundation base and deep slide in the foundation. The portland cement usually had to be aged to comply with a. Gravity dams are solid concrete structures that maintain their stability against design loads from the geometric shape and the mass and strength of the concrete. The structural analysis of an existing concrete gravity dam was aimed at assessing the extent of structural damage caused by the reaction. Structural assessment of the mignano solid gravity dam based on the monitoring data.
Cooling and insulating systems for mass concrete are addressed in aci 207. Within parts i and ii, each criterion is discussed under its appropriate subject heading. Simplified earthquake analysis of concrete gravity dams. Pdf seismic stability analysis of concrete gravity dams.
Cadam is primarily designed to provide support for learning the principles of structural stability evaluation of gravity dams. The book aims to discuss the latest developments in computational theories on multiplecrack analysis and mixedmode fracture in structural concrete and the application of these theories to solve important engineering problems. Several researches disclosed that the methods used to design and reevaluate concrete gravity dams after the 1970s have shown significant advancement. Stability analysis of concrete gravity dam on complicated. Gravity dams are designed so that each section of the dam is stable and independent of any other dam section. Previous ferc gravity dam guidance dealt with nappe forces by ignoring the weight of the nappe.
Following an overview of centrifugal testing, this paper reports on the first centrifuge testing of concrete gravity dam models. A gravity dam is an essentially solid concrete structure that resists imposed forces principally by its own weight. The mechanical behavior of the concrete material is modeled using the concrete damaged plasticity constitutive model described in concrete damaged plasticity, section 18. Probabilistic finite element analysis of concrete gravity dams.
Even though stability analysis of concrete structures is a structural engineering responsibility, the analysis. If the density of concrete is 2400 kgm 3 and that of water is kgm 3, determine the maximum compressive stress at section mn if the depth of the water behind the dam is h 15 m. Structural dynamics and earthquake engineering books. Deep antislide stability is a more complicated problem than shallow antislide stability. Fragility analysis of concrete gravity dams journal of. Dec 17, 2017 modelling and apply pushover and cyclic load test on beam column by abaqus and get hysteresis loop duration. Types of concrete gravity dams introduction gravity dams are solid concrete structures that maintain their stability against design loads. This paper presents a summary of a structural analysis methodologies to assess the seismic cracking and sliding responses of concrete gravity dams including transient uplift pressures in cracks, b related computer programs, c dam strengthening using posttension anchors, and d related experimental validation work. The weight of gravity dam will cause a moment opposite to the overturning moment and the friction on the base will prevent the dam from sliding.
Based on a nonlinear approach, seismic safety evaluation of concrete dams allows engineers to build models that account for nonlinear phenomena such as vertical joint slippage, cracks, and cavitation. This manual presents analysis and design guidance for concrete gravity dams. In gravity dams, crack growth is inhibited by gravitational effects. Learning outcome after this lecture, students should be able to 1. The stability of concrete gravity dam is analyzed by. Pdf concrete dams are vital structures regarding catastrophic impacts in cases of dam failure.
Earthquake response analysis of concrete dams springerlink. This starts when contemporary structural analysis methods such as a finite element. Analysis of the stability is generally conducted at the dam base rock concrete contact and at selected planes within the dam. Analysis of gravity dam dams are structures whose purpose is to raise the water level on the upstream side of river, stream, or other waterway. An important issue regarding the engineering procedures as practiced by all three agencies when performing stability calculations is how uplift water. During the service life of a dam, operating conditions and natural environmental factors may have led to some deterioration in its structural integrity, mechanical equipment, and foundation. Concrete gravity dams are an important part of the nations infrastructure. Seismic safety evaluation of concrete dams 1st edition. Following its introduction, this monograph is divided into part i, arch dams, and part ii, gravity dams. Earthquake damage analysis of concrete gravity dams. A comprehensive guide to modernday methods for earthquake engineering of concrete dams. Gravity dams may be classified by plan as straight gravity dams and curved gravity. The code automates the prediction and evaluation of cracking in the dam, along the damrock interface, and in the foundation using incremental nonlinear analysis techniques based on. The nile delta contributed book project published by springer.
The dam was composed of 100,000 tons of rubble, gravel, and stone. Uplift pressures, shear strengths, and tensile strengths for. After demonstrating that traditional design procedures are unrealistic, a method for design of concrete gravity dams to remain essentially within the elastic range of behavior is presented. The code automates the prediction and evaluation of cracking in the dam, along the dam rock interface, and in the foundation using incremental nonlinear analysis techniques based on. This necessitates the seismic analysis of concrete gravity dams. Earthquake analysis of concrete gravity dam springerlink. The concrete material remains elastic with no damage at the end of the second step, after the dam has been subjected to the gravity and hydrostatic pressure loads. Finite element analysis structural dynamics fluid mechanics 7. A procedure for the timedomain analysis of gravity damreservoir interaction is proposed. This chapter introduces a book that focuses on the fracture mechanics of structural concrete. A general procedure for analysis of the response of concrete gravity dams, including the dynamic effects of impounded water and flexible foundation rock, to the transverse horizontal and vertical components of earthquake ground motion is presented. Seismic safety evaluation of concrete dams sciencedirect. Relation of the course to past and future studies students are required to be familiar with the following subjects.
For this type of dam, impervious foundations with high bearing strength are essential. Jul 27, 2014 seismic analysis of concrete gravity dam using fem 1. This paper presents a finite element modelling procedure to determine the thermal response of concrete gravity dams. Lowlevel outlet is an opening at a low level used to drain or lower the water.
Reinforced concrete structures explains the underlying principles of reinforced concrete design and covers the analysis, design, and detailing requirements in the 2008 american concrete institute aci building code requirements for structural concrete and commentary and the 2009 international code council icc. The nile delta contributed book project published by springer international publishing in 2017. The pressure due to this seepage is commonly called hydrostatic uplift and will reduce the stability of the dam against sliding and against overturning. In 19982003, he served as the rcc design task leader for the olivenhain dam in san diego, california. In this work the study of these factorswas made according to two standard method s, usbr and usace, which are varied in the. This technical report summarizes the results of an investigation of key aspects of guidance published by the corps, reclamation, and ferc used to calculate the stability of gravity dam sections. Final report, author, abstractnote this report presents the results of a threeyear study of uplift pressures and strengths which are used for stability evaluations of concrete gravity dams. Structural assessment of the mignano solidgravity dam.
Safety factors play an important role in the analysis of structural s tability of gravity concrete dams. Journal of earthquake engineering and structural dynamics, 9, 363383. A stress analysis of gravity dams is performed by two methods. Pdf static and dynamic analysis of concrete gravity dams. History shows that several dams were failed and discharged the stored water which causes incalculable damage on life and property. Seismic stability of concrete gravity dams leger 1989. Curved gravity dams designed for arch action and other types of concrete gravity dams are not covered in this manual.
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