Gravity Dam Design - United States Army

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EM 1110-2-220030 June 1995US Army Corpsof EngineersENGINEERING AND DESIGNGravity Dam DesignENGINEER MANUAL

AVAILABILITYCopies of this and other U.S. Army Corps of Engineers publications are available from National Technical InformationService, 5285 Port Royal Road, Springfield, VA 22161.Phone (703)487-4650.Government agencies can order directlyu from the U.S. ArmyCorps of Engineers Publications Depot, 2803 52nd Avenue,Hyattsville, MD 20781-1102. Phone (301)436-2065. U.S.Army Corps of Engineers personnel should use Engineer Form0-1687.UPDATESFor a list of all U.S. Army Corps of Engineers publicationsand their most recent publication dates, refer to EngineerPamphlet 25-1-1, Index of Publications, Forms and Reports.

CECW-EDDEPARTMENT OF THE ARMYU.S. Army Corps of EngineersWashington, DC 20314-1000ManualNo. 1110-2-2200EM 1110-2-220030 June 1995Engineering and DesignGRAVITY DAM DESIGN1. Purpose. The purpose of this manual is to provide technical criteria and guidance for the planningand design of concrete gravity dams for civil works projects.2. Applicability. This manual applies to all HQUSACE elements, major subordinate commands,districts, laboratories, and field operating activities having responsibilities for the design of civil worksprojects.3. Discussion. This manual presents analysis and design guidance for concrete gravity dams.Conventional concrete and roller compacted concrete are both addressed. Curved gravity damsdesigned for arch action and other types of concrete gravity dams are not covered in this manual. Forstructures consisting of a section of concrete gravity dam within an embankment dam, the concretesection will be designed in accordance with this manual.FOR THE COMMANDER:This engineer manual supersedes EM 1110-2-2200 dated 25 September 1958.

DEPARTMENT OF THE ARMYU.S. Army Corps of EngineersWashington, DC 20314-1000CECW-EDEM 1110-2-2200ManualNo. 1110-2-220030 June 1995Engineering and DesignGRAVITY DAM DESIGNTable of ContentsSubjectChapter 1IntroductionPurpose . . . .Scope . . . . . .Applicability .References . .Terminology .Paragraph.Chapter 2General Design ConsiderationsTypes of Concrete Gravity Dams . . .Coordination Between Disciplines . .Construction Materials . . . . . . . . . .Site Selection . . . . . . . . . . . . . . . .Determining Foundation StrengthParameters . . . . . . . . . . . . . . . . .1-11-11-11-11-1SubjectParagraphChapter 5Static and Dynamic StressAnalysesStress Analysis . . . . . . . . . . . . . . .Dynamic Analysis . . . . . . . . . . . . .Dynamic Analysis Process . . . . . . .Interdisciplinary Coordination . . . . .Performance Criteria for Response toSite-Dependent Earthquakes . . . . .Geological and SeismologicalInvestigation . . . . . . . . . . . . . . . .Selecting the Controlling EarthquakesCharacterizing Ground Motions . . . .Dynamic Methods of Stress 85-95-25-25-35-42-12-22-32-42-12-22-32-3. 2-52-4Chapter 3Design DataConcrete Properties . . . . . . . . . . . . . 3-1Foundation Properties . . . . . . . . . . . . 3-2Loads . . . . . . . . . . . . . . . . . . . . . . . 3-33-13-23-3Chapter 6Temperature Control of MassConcreteIntroduction . . . . . . . . . . . . . . .Thermal Properties of Concrete . .Thermal Studies . . . . . . . . . . . . .Temperature Control Methods . . 0Chapter 7Structural Design ConsiderationsIntroduction . . . . . . . . . . . . . . . . . 7-1Contraction and Construction Joints . 7-2Waterstops . . . . . . . . . . . . . . . . . . 7-3Spillway . . . . . . . . . . . . . . . . . . . . 7-4Spillway Bridge . . . . . . . . . . . . . . . 7-5Spillway Piers . . . . . . . . . . . . . . . . 7-6Outlet Works . . . . . . . . . . . . . . . . . 7-7Foundation Grouting and Drainage . . 7-87-17-17-17-17-27-27-37-3Chapter 4Stability AnalysisIntroduction . . . . . . . . .Basic Loading ConditionsDam Profiles . . . . . . . . .Stability Considerations .Overturning Stability . . .Sliding Stability . . . . . . .Base Pressures . . . . . . . .Computer Programs . . . .1-11-21-31-41-5Page.4-14-24-34-44-54-64-74-8.i

EM 1110-2-190630 Sep 96SubjectParagraphGalleries . . . . . . . . . . . . . . . . . . . . . 7-9Instrumentation . . . . . . . . . . . . . . . . 7-10Chapter 8Reevaluation of Existing DamsGeneral . . . . . . . . . . . . . . . . . . . . .Reevaluation . . . . . . . . . . . . . . . . .Procedures . . . . . . . . . . . . . . . . . .Considerations of Deviation fromStructural Criteria . . . . . . . . . . . .Structural Requirements for RemedialMeasure . . . . . . . . . . . . . . . . . . .Methods of Improving Stability inExisting Structures . . . . . . . . . . . .Stability on Deep-Seated FailurePlanes . . . . . . . . . . . . . . . . . . . .Example Problem . . . . . . . . . . . . . .PageSubject7-37-4Economic Benefits . . . . . . . . . . . . . 9-3Design and ConstructionConsiderations . . . . . . . . . . . . . . . 9-4. 8-1. 8-2. 8-38-18-18-1. 8-48-2. 8-58-2. 8-68-2. 8-7. 8-88-38-4Chapter 9Roller-Compacted ConcreteGravity DamsIntroduction . . . . . . . . . . . . . . . . . . 9-1Construction Method . . . . . . . . . . . . 9-28-19-1iiAppendix AReferencesAppendix BGlossaryAppendix CDerivation of the GeneralWedge EquationAppendix DExample Problems - SlidingAnalysis for Single andMultiple Wedge SystemsParagraphPage9-19-3

EM 1110-2-220030 Jun 95Chapter 1Introduction1-1. PurposeThe purpose of this manual is to provide technical criteriaand guidance for the planning and design of concretegravity dams for civil works projects. Specific areascovered include design considerations, load conditions,stability requirements, methods of stress analysis, seismicanalysis guidance, and miscellaneous structural features.Information is provided on the evaluation of existingstructures and methods for improving stability.1-2. Scopea. This manual presents analysis and design guidancefor concrete gravity dams. Conventional concrete androller compacted concrete (RCC) are both addressed.Curved gravity dams designed for arch action and othertypes of concrete gravity dams are not covered in thismanual. For structures consisting of a section of concretegravity dam within an embankment dam, the concretesection will be designed in accordance with this manual.b. The procedures in this manual cover only damson rock foundations. Dams on pile foundations should bedesigned according to Engineer Manual(EM) 1110-2-2906.c. Except as specifically noted throughout themanual, the guidance for the design of RCC and conventional concrete dams will be the same.1-3. ApplicabilityThis manual applies to all HQUSACE elements, majorsubordinate commands, districts, laboratories, and fieldoperating activities having responsibilities for the designof civil works projects.1-4. ReferencesRequired andAppendix A.relatedpublicationsarelistedin1-5. TerminologyAppendix B contains definitions of terms that relate to thedesign of concrete gravity dams.This engineer manual supersedes EM 1110-2-2200 dated25 September 1958.1-1

EM 1110-2-220030 June 95Chapter 2General Design Considerations2-1. Types of Concrete Gravity DamsBasically, gravity dams are solid concrete structures thatmaintain their stability against design loads from thegeometric shape and the mass and strength of the concrete. Generally, they are constructed on a straight axis,but may be slightly curved or angled to accommodate thespecific site conditions. Gravity dams typically consist ofa nonoverflow section(s) and an overflow section or spillway. The two general concrete construction methods forconcrete gravity dams are conventional placed mass concrete and RCC.a.Conventional concrete dams.(1) Conventionally placed mass concrete dams arecharacterized by construction using materials and techniques employed in the proportioning, mixing, placing,curing, and temperature control of mass concrete (American Concrete Institute (ACI) 207.1 R-87). Typical overflow and nonoverflow sections are shown on Figures 2-1and 2-2. Construction incorporates methods that havebeen developed and perfected over many years of designing and building mass concrete dams. The cement hydration process of conventional concrete limits the size andrate of concrete placement and necessitates building inmonoliths to meet crack control requirements. Generallyusing large-size coarse aggregates, mix proportions areselected to produce a low-slump concrete that gives economy, maintains good workability during placement, develops minimum temperature rise during hydration, andproduces important properties such as strength, impermeability, and durability. Dam construction with conventional concrete readily facilitates installation of conduits,penstocks, galleries, etc., within the structure.(2) Construction procedures include batching andmixing, and transportation, placement, vibration, cooling,curing, and preparation of horizontal construction jointsbetween lifts. The large volume of concrete in a gravitydam normally justifies an onsite batch plant, and requiresan aggregate source of adequate quality and quantity,located at or within an economical distance of the project.Transportation from the batch plant to the dam is generally performed in buckets ranging in size from 4 to12 cubic yards carried by truck, rail, cranes, cableways, ora combination of these methods. The maximum bucketsize is usually restricted by the capability of effectivelyspreading and vibrating the concrete pile after it isdumped from the bucket. The concrete is placed in liftsof 5- to 10-foot depths. Each lift consists of successivelayers not exceeding 18 to 20 inches. Vibration is generally performed by large one-man, air-driven, spud-typevibrators. Methods of cleaning horizontal constructionjoints to remove the weak laitance film on the surfaceduring curing include green cutting, wet sand-blasting,and high-pressure air-water jet. Additional details ofconventional concrete placements are covered inEM 1110-2-2000.(3) The heat generated as cement hydrates requirescareful temperature control during placement of mass concrete and for several days after placement. Uncontrolledheat generation could result in excessive tensile stressesdue to extreme gradients within the mass concrete or dueto temperature reductions as the concrete approaches itsannual temperature cycle. Control measures involve precooling and postcooling techniques to limit the peak temperatures and control the temperature drop. Reduction inthe cement content and cement replacement with pozzolans have reduced the temperature-rise potential. Crackcontrol is achieved by constructing the conventional concrete gravity dam in a series of individually stable monoliths separated by transverse contraction joints. Usually,monoliths are approximately 50 feet wide. Further detailson temperature control methods are provided inChapter 6.b. Roller-compacted concrete (RCC) gravity dams.The design of RCC gravity dams is similar to conventional concrete structures. The differences lie in the construction methods, concrete mix design, and details of theappurtenant structures. Construction of an RCC dam is arelatively new and economical concept. Economic advantages are achieved with rapid placement using construction techniques that are similar to those employed forembankment dams. RCC is a relatively dry, lean, zeroslump concrete material containing coarse and fine aggregate that is consolidated by external vibration using vibratory rollers, dozer, and other heavy equipment. In thehardened condition, RCC has similar properties to conventional concrete. For effective consolidation, RCC must bedry enough to support the weight of the constructionequipment, but have a consistency wet enough to permitadequate distribution of the past binder throughout themass during the mixing and vibration process and, thus,achieve the necessary compaction of the RCC and prevention of undesirable segregation and voids. The consistency requirements have a direct effect on the mixture proportioning requirements (ACI 207.1 R-87). EM 11102-2006, Roller Compacted Concrete, provides detailed2-1

EM 1110-2-220030 June 95Figure 2-1. Typical dam overflow sectionguidance on the use, design, and construction of RCC.Further discussion on the economic benefits and thedesign and construction considerations is provided inChapter 9.mechanisms, and other related features of the analyticalmodels. The structural engineer should be involved inthese activities to obtain a full understanding of the limitsof uncertainty in the selection of loads, strength parameters, and potential planes of failure within the foundation.2-2. Coordination Between DisciplinesA fully coordinated team of structural, material, and geotechnical engineers, geologists, and hydrological andhydraulic engineers should ensure that all engineering andgeological considerations are properly integrated into theoverall design. Some of the critical aspects of the analysis and design process that require coordination are:a. Preliminary assessments of geological data, subsurface conditions, and rock structure.Preliminarydesigns are based on limited site data. Planning andevaluating field explorations to make refinements indesign based on site conditions should be a joint effort ofstructural and geotechnical engineers.b. Selection of material properties, design parameters, loading conditions, loading effects, potential failure2-2c. Evaluation of the technical and economic feasibility of alternative type structures. Optimum structuretype and foundation conditions are interrelated. Decisionson alternative structure types to be used for comparativestudies need to be made jointly with geotechnical engineers to ensure the technical and economic feasibility ofthe alternatives.d. Constructibility reviews in accordance withER 415-1-11. Participation in constructibility reviews isnecessary to ensure that design assumptions and methodsof construction are compatible. Constructibility reviewsshould be followed by a memorandum from the Directorate of Engineering to the Resident Engineer concerningspecial design considerations and scheduling of construction visits by design engineers during crucial stages ofconstruction.

EM 1110-2-220030 June 95quality control structures need to be developed jointlywith hydrologists and mechanical and hydraulicsengineers.h. Modification to the structure configuration during construction due to unexpected variations in the foundation conditions. Modifications during construction arecostly and should be avoided if possible by a comprehensive exploration program during the design phase. However, any changes in foundation strength or rock structurefrom those upon which the design is based must be fullyevaluated by the structural engineer.2-3. Construction MaterialsFigure 2-2. Nonoverflow sectione. Refinement of the preliminary structure configuration to reflect the results of detailed site explorations,materials availability studies, laboratory testing, andnumerical analysis. Once the characteristics of the foundation and concrete materials are defined, the foundinglevels of the dam should be set jointly by geotechnicaland structural engineers, and concrete studies should bemade to arrive at suitable mixes, lift thicknesses, andrequired crack control measures.f. Cofferdam and diversion layout, design, andsequencing requirements. Planning and design of thesefeatures will be based on economic risk and require thejoint effort of hydrologists and geotechnical, construction,hydraulics, and structural engineers. Cofferdams must beset at elevations which will allow construction to proceedwith a minimum of interruptions, yet be designed to allowcontrolled flooding during unusual events.g. Size and type of outlet works and spillway. Thesize and type of outlet works and spillway should be setjointly with all disciplines involved during the early stagesof design. These features will significantly impact on theconfiguration of the dam and the sequencing of construction operations. Special hydraulic features such as waterThe design of concrete dams involves consideration ofvarious construction materials during the investigationsphase. An assessment is required on the availability andsuitability of the materials needed to manufacture concretequalities meeting the structural and durability requirements, and of adequate quantities for the volume of concrete in the dam and appurtenant structures. Constructionmaterials include fine and coarse aggregates, cementitiousmaterials, water for washing aggregates, mixing, curing ofconcrete, and chemical admixtures. One of the mostimportant factors in determining the quality and economyof the concrete is the selection of suitable sources ofaggregate. In the construction of concrete dams, it isimportant that the source have the capability of producingadequate quantitives for the economical production ofmass concrete. The use of large aggregates in concretereduces the cement content. The procedures for theinvestigation of aggregates shall follow the requirementsin EM 1110-2-2000 for mass concrete and EM 1110-22006 for RCC.2-4. Site Selectiona. General. During the feasibility studies, thepreliminary site selection will be dependent on the projectpurposes within the Corps’ jurisdiction. Purposes applicable to dam construction include navigation, flood damage reduction, hydroelectric power generation, fish andwildlife enhancement, water quality, water supply, andrecreation. The feasibility study will establish the mostsuitable and economical location and type of structure.Investigations will be performed on hydrology and meteorology, relocations, foundation and site geology, construction materials, appurtenant features, environmentalconsiderations, and diversion methods.2-3

EM 1110-2-220030 June 95b.Selection factors.(1) A concrete dam requires a sound bedrock foundation. It is important that the bedrock have adequate shearstrength and bearing capacity to meet the necessary stability requirements. When the dam crosses a major faultor shear zone, special design features (joints, monolithlengths, concrete zones, etc.) should be incorporated in thedesign to accommodate the anticipated movement. Allspecial features should be designed based on analyticaltechniques and testing simulating the fault movement.The foundation permeability and the extent and cost offoundation grouting, drainage, or other seepage and upliftcontrol measures should be investigated. The reservoir’ssuitability from the aspect of possible landslides needs tobe thoroughly evaluated to assure that pool fluctuationsand earthquakes would not result in any mass sliding intothe pool after the project is constructed.(2) The topography is an important factor in theselection and location of a concrete dam and itsappurtenant structures. Construction as a site with a narrow canyon profile on sound bedrock close to the surfaceis preferable, as this location would minimize the concretematerial requirements and the associated costs.(3) The criteria set forth for the spillway, powerhouse, and the other project appurtenances will play animportant role in site selection. The relationship andadaptability of these features to the project alignment willneed evaluation along with associated costs.(4) Additional factors of lesser importance that needto be included for consideration are the relocation ofexisting facilities and utilities that lie within the reservoirand in the path of the dam. Included in these are railroads, powerlines, highways, towns, etc. Extensive andcostly relocations should be avoided.(6) The method or scheme of diverting flows aroundor through the damsite during construction is an importantconsideration to the economy of the dam. A concretegravity dam offers major advantages and potential costsavings by providing the option of diversion throughalternate construction blocks, and lowers risk and delay ifovertopping should occur.2-5. Determining Foundation StrengthParametersa. General.Foundation strength parameters arerequired for stability analysis of the gravity dam section.Determination of the required parameters is made by2-4evaluation of the most appropriate laboratory and/or insitu strength tests on representative foundation samplescoupled with extensive knowledge of the subsurface geologic characteristics of a rock foundation. In situ testingis expensive and usually justified only on very largeprojects or when foundation problems are know to exist.In situ testing would be appropriate where more precisefoundation parameters are required because rock strengthis marginal or where weak layers exist and in situproperties cannot be adequately determined from laboratory testing of rock samples.b. Field investigation. The field investigation mustbe a continual process starting with the preliminary geologic review of known conditions, progressing to adetailed drilling program and sample testing program, andconcluding at the end of construction with a safe andoperational structure. The scope of investigation andsampling should be based on an assessment of homogeneity or complexity of geological structure. For example, theextent of the investigation could vary from quite limited(where the foundation material is strong even along theweakest potential failure planes) to quite extensive anddetailed (where weak zones or seams exist). There is acertain minimum level of investigation necessary to determine that weak zones are not present in the foundation.Field investigations must also evaluate depth and severityof weathering, ground-water conditions (hydrogeology),permeability, strength, deformation characteristics, andexcavatibility. Undisturbed samples are required to determine the engineering properties of the foundation materials, demanding extreme care in application and samplingmethods. Proper sampling is a combination of scienceand art; many procedures have been standardized, butalteration and adaptation of techniques are often dictatedby specific field procedures as discussed inEM 1110-2-1804.c. Strength testing. The wide variety of foundationrock properties and rock structural conditions preclude astandardized universal approach to strength testing. Decisions must be made concerning the need for in situ testing. Before any rock testing is initiated, the geotechnicalengineer, geologist, and designer responsible for formulating the testing program must clearly define what the purpose of each test is and who will supervise the testing. Itis imperative to use all available data, such as resultsfrom geological and geophysical studies, when selectingrepresentative samples for testing. Laboratory testingmust attempt to duplicate the actual anticipated loadingsituations as closely as possible. Compressive strengthtesting and direct shear testing are normally required todetermine design values for shear strength and bearing

EM 1110-2-220030 June 95capacity. Tensile strength testing in some cases as wellas consolidation and slakeability testing may also benecessary for soft rock foundations. Rock testing procedures are discussed in the Rock Testing Handbook(US Army Engineer Waterways Experiment Station(WES) 1980) and in the International Society of RockMechanics, “Suggested Methods for Determining ShearStrength,” (International Society of Rock Mechanics1974). These testing methods may be modified as appropriate to fit the circumstances of the project.d. Design shear strengths. Shear strength valuesused in sliding analyses are determined from availablelaboratory and field tests and judgment. For preliminarydesigns, appropriate shear strengths for various types ofrock may be obtained from numerous available referencesincluding the US Bureau of Reclamation Reports SP-39and REC-ERC-74-10, and many reference texts (see bibliography). It is important to select the types ofstrengthtests to be performed based upon the probablemode of failure. Generally, strengths on rock discontinuities would be used for the active wedge and beneath thestructure. A combination of strengths on discontinuitiesand/or intact rock strengths would be used for the passivewedge when included in the analysis. Strengths alongpreexisting shear planes (or faults) should be determinedfrom residual shear tests, whereas the strength along othertypes of discontinuities must consider the strain characteristics of the various materials along the failure plane aswell as the effect of asperities.2-5

EM 1110-2-220030 Jun 95Chapter 3Design Databy the linear relationship T C δ tan φ in which C isthe unit cohesive strength, δ is the normal stress, and tanφ represents the coefficient of internal friction.3-1. Concrete Properties(4) The splitting tension test (ASTM C 496) or themodulus of rupture test (ASTM C 78) can be used todetermine the strength of intact concrete. Modulus ofrupture tests provide results which are consistent with theassumed linear elastic behavior used in design. Spittingtension test results can be used; however, the designershould be aware that the results represent nonlinear performance of the sample. A more detailed discussion ofthese tests is presented in the ACI Journal (Raphael1984).a. General. The specific concrete properties used inthe design of concrete gravity dams include the unitweight, compressive, tensile, and shear strengths, modulusof elasticity, creep, Poisson’s ratio, coefficient of thermalexpansion, thermal conductivity, specific heat, and diffusivity. These same properties are also important in thedesign of RCC dams. Investigations have generally indicated RCC will exhibit properties equivalent to those ofconventional concrete. Values of the above propertiesthat are to be used by the designer in the reconnaissanceand feasibility design phases of the project are availablein ACI 207.1R-87 or other existing sources of informationon similar materials. Follow-on laboratory testing andfield investigations should provide the values necessary inthe final design. Temperature control and mix design arecovered in EM 1110-2-2000 and Em 1110-2-2006.b. Strength.(1) Concrete strength varies with age; the type ofcement, aggregates, and other ingredients used; and theirproportions in the mixture. The main factor affectingconcrete strength is the water-cement ratio. Lowering theratio improves the strength and overall quality. Requirements for workability during placement, durability, minimum temperature rise, and overall economy may governthe concrete mix proportioning. Concrete strengths shouldsatisfy the early load and construction requirements andthe stress criteria described in Chapter 4. Design compressive strengths at later ages are useful in taking fulladvantage of the strength properties of the cementitiousmaterials and lowering the cement content, resulting inlower ultimate internal temperature and lower potentialcracking incidence. The age at which ultimate strength isrequired needs to be carefully reviewed and revised whereappropriate.(2) Compressive strengths are determined from thestandard unconfined compression test excluding creepeffects (American Society for Testing and Materials(ASTM) C 39, “Test Method for Compressive Strength ofCylindrical Concrete Specimens”; C 172, “Method ofSampling Freshly Mixed Concrete”; ASTM C 31,“Method of Making and Curing Concrete Test Specimensin the Field”).(3) The shear strength along construction joints or atthe interface with the rock foundation can be determinedc. Elastic properties.(1) The graphical stress-strain relationship for concrete subjected to a continuously increasing load is acurved line. For practical purposes, however, the modulus of elasticity is considered a constant for the range ofstresses to which mass concrete is usually subjected.(2) The modulus of elasticity and Poisson’s ratio aredetermined by the ASTM C 469, “Test Method for StaticModulus of Elasticity and Poisson’s Ratio of Concrete inCompression.”(3) The deformation response of a concrete damsubjected to sustained stress can be divided into two parts.The first, elastic deformation, is the strain measuredimmediately after loading and is expressed as the instantaneous modulus of elasticity. The other, a gradual yieldingover a long period, is the inelastic deformation or creep inconcrete. Approximate values for creep are generallybased on reduced values of the instantaneous modulus.When design requires more exact values, creep should bebased on the standard test for creep of concrete in compression (ASTM C 512).d. Thermal properties. Thermal studies are requiredfor gravity dams to assess the effects of stresses inducedby temperature changes in the concrete and to determinethe temperature controls necessary to avoid undesirablecracking. The thermal properties required in the studyinclude thermal conductivity, thermal diffusivity, specificheat, and the coefficient of thermal expansion.e. Dynamic properties.(1) The concrete properties required for input into alinear elastic dynamic analysis are the unit weight,Young’s modulus of elasticity, and Poisson’s ratio. The3-1

EM 1110-2-220030 Jun 95concrete tested should be of sufficient age to represent theultimate concrete properties as nearly as practicable.One-year-old specimens are preferred. Usually, upper andlower bound values of Young’s modulus of elasticity willbe required to bracket the possibilities.(2) The concrete properties needed to evaluate theresults of the dynamic analysis are the compressive andtensile strengths. The standard compression test (seeparagraph 3-1b) is acceptable, even though it does notaccount for the rate of loading, since compression normally does not control in the dynamic analysis. Thesplitting tensile test or the modulus of rupture test can beused to determine the tensile strength. The static tensilestrength determined by the spl

b. Roller-compacted concrete (RCC) gravity dams. The design of RCC gravity dams is similar to conven-tional concrete structures. The differences lie in the con-struction methods, concrete mix design, and details of the appurtenant structures. Construction of an RCC dam is

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