ACI318-08 Building Code Requirements for Structural Concrete and Commentary

9.1General.. ..115 9.2—Required strength .115 9.3—Design strength .... 9.4—Design strength for reinforcement. 9.5—Control of deflections. 121

MANUAL OF CONCRETEPRACTICE

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16.7Items embedded after concrete placement .275 16..8Marking and identification............... ..275 16.9—Handling .... .275 16.10—Strength evaluation of precast construction .275

给排水造价、定额、预算17.1—Scope... .27 17.2General. 277 17.3—Shoring .278 17.4—Vertical shear strength. ..278 17.5—Horizontal shear strength ..278 17.6Ties for horizontal shear 279

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STRUCTURAL CONCRETE BUILDING CODE/COMMENTAF

e ACl Building Code Requirements for Structural Concrete (Code") and Commentary are presented in a sidd umn format, with Code text placed in the left column and the corresponding Commentary text aligned in the right further distinguish the Code from the Commentary, the Code has been printed in Helvetica, the same type face sparagraph is set.

INTRODUCTON

Ihe Code is intended to cover all buildings of the usual types, both large and small.Requirements more stringent han the Code provisions may be desirable for unusual construction.The Code and Commentary cannot replace soundengineeringknowledge,experience, and judgment.

A building code states only the minimum requirements necessary to provide for public health and safety. The Code is based on this principle. For any structure, the owner or the licensed design professional may require the quality of materials and construction to be higher than the minimum

For a history of the ACI Building Code see Kerekes, F, and Reid, H, B., Jr., "Fifty Years of Development in Building Code Requirements for Reinforced Concrete," ACI and Engineering Practice," ACI JoURNAL, Proceedings V. 56, No. 5, May 1960, p. 1105.

requirements necessary to protect the public as stated in the Code. However, lower standards are not permitted.

The Commentary directs attention to other documents that provide suggestions for carrying out the requirements and intent of theCode.However,those documents and the Commentary are not a part of the Code.

The Code has no legal status unless it is adopted by the government bodies having the police power to regulate building design and construction. Where the Code has not been adopted, it may serve as a reference to good practice even though it has no legal status.

Design reference materials illustrating applications of the Code requirements may be found in the following documents. The design aids listed may be obtained from the sponsoring organization

Design aids:

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MANUAL OF CONCRETE PRACTICE

The chapters onfoundationsprovidedesigntablesforsquare footings, pile caps, drilled piers (caissons), and cantilevered retaining walls. Other design aids are presented for crack control; and development of reinforcement and lap splices.)

"Reinforcement Anchorages and Splices," Concrete Reinforcing Steel Institute, Schaumburg, IL, 4th Edition. 1997, 100 pp. (This provides accepted practices in splicing einforcement. The use of lap splices, mechanical splices. and welded splices are described. Design data are presented for development and lap splicing of reinforcement.)

"Structural Welded Wire Reinforcement Manual of Stan

ctural Welded Wire Reinforcement Detailing

Design and Typical Details of Connections for Precast anc Prestressed Concrete, Precast/Prestressed Concrete Institute, Chicago, IL, 2nd Edition, 1988, 270 pp. (This updates available nformation on design of connections for both structural and architectural products, and presents a full spectrum of typical details. This provides design aids and examples.)

STRUCTURAL CONCRETE BUILDING CODE/COMMENTAR

1.1.1 — This Code provides minimum requirements for design and construction of structural concrete membersofanystructureerectedunderrequirements of the legally adopted general building code of which this Code forms a part. In areas without a legally adopted building code, this Code defines minimum acceptable standardsfor materials,design,and construction practice. This Code also covers the strength evaluation of existing concrete structures. For structural concrete,f: shall not be lessthan 2500psi.Nomaximumvalue offshall apply unless restricted by a specific Code provision.

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COMMENTARY

Prestressed concrete is included under the definition of reinforced concrete.Provisions of the Code apply to prestressed concrete except for those that are stated to apply specifically to nonprestressed concrete.

Appendix A of Codes prior to 2002 contained provisions for an alternate method of designfor nonprestressed reinforced concrete members using service loads (without load factors) and permissible service load stresses. The Alternate Design Method was intended to give results that were slightly more conservative than designs by the Strength Design Method of the Code. The Alternate Design Method of the 1999 Code may be used inplace of applicable sections of this Code

Appendix A of the Code contains provisions for the design of regions near geometrical discontinuities, or abrupt changes in loadings.

1.1.2 —This Code supplements the general building code and shall govern in all matters pertaining to design and construction of structural concrete, except wherever this Code is in conflict with requirements in thelegallyadoptedgeneralbuildingcode

1.1.3This Code shallgovern inall matterspertaining odesign,construction,andmaterialpropertieswherever his Code is in conflict with requirements contained in otherstandardsreferencedinthisCode

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"Code for Concrete Containments"reported by Joint for the design, construction, and use of concrete reactor wessels and concrete containment structures for nuclear power plants.)

R1.1.6 The design andinstallationof piling fully embedded in the ground is regulated by the general building code. For portions of piling in air or water, or in soil not capable of providing adequatelateral restraint throughout the piling length to prevent buckling, the design provisions of this code govern where applicable.

1.1.9Provisionsforearthquakeresistance

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COMIMENTARY

R1.1.9Provisions for earthquake resistance

Seismic Design Categories in this Code are adopted directly are used by the 2006 edition of the “International Building Construction and Safety Code.l.16 The “BOCA National Building Code" (NBC)l.17 and "Standard Building Code" (SBC)1.18 use Seismic PerformanceCategories.The 1997 requirements to seismic zones, whereas previous editions of ACI 318 related seismic design requirements to seismic risk levels. Table R1.1.9.1 correlates Seismic Design Categories to the low, moderate/intermediate, and high seismic risk terminology used in ACI 318 for several editions before the 2008 edition, and to the various methods of assigning design requirements in use in the U.S. under the various model building codes, the ASCE/SEI 7 standard, and the

STRUCTURAL CONCRETE BUILDING CODE/COMMENTAR

This Code does not govern design and construction of tanks and reservoirs.

1.2.1—Copies of design drawings, typical details, and specifications for all structural concrete construction shall bear the seal of a licensed design professional. These drawings, details, and specifications shall show:

(a) Name and date of issue of code and supplement to which design conforms;

[b) Live load and other loads used in design:

In the absence of a general building code that prescribes earthquake loads and seismic zoning, it is the intent of Committee 318 that application of provisions for seismic design be consistent with national standards or model building codes such as References 1.14. 1.15, and 1.16.

R1.1.9.2 Structures assigned to Seismic design category (SDC) A have the lowest seismic hazard and performance requirements. Provisions of Chapters 1 through 19 and Chapter 22 are considered sufficient for these structures. For structures assigned to other SDCs, the design requirements of Chapter 21 apply, as delineated in 21.1

R1.2Drawingsand specifications

R1.2.1 The provisions for preparation of design drawings and specifications are, in general, consistent with those of most general building codes and are intended as supplements

Provision for dimensional changes resulting from eep,shrinkage,andtemperature;

(g)Magnitude and location of prestressing forces; (h)Anchorage length of reinforcement and location and length of lap splices; (i)Typeandlocation of mechanical andwelded Snlices of rainforcamant:

i) Type and location of mechanical and welded splicesofreinforcement:

1.3Inspection

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The Code permits model analysis to be used to supplement structural analysis and design calculations.Documentation of the model analysis should be provided with the related calculations.Model analysis should be performed by an individual having experience in this technique.

R1.3Inspection

STRUCTURAL CONCRETE BUILDING CODE/COMMENTAR

1.3.1 Concrete construction shall be inspectedas required by the legally adopted general building code.In theabsenceof such inspectionrequirements,concrete construction shall be inspected throughout the various Work stages by or under the supervision of a licensed design professional orby a qualified inspector.

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performed well. Inspection is necessary to confirm that the construction is in accordance with the design drawings and project specifications. Proper performance of the structure depends on construction that accurately represents the design and meets code requirements within the tolerances allowed.Qualification of the inspectors canbe obtained from a certification program, such as the ACI Certification Program for Concrete Construction Special Inspector

R1.3.1 Inspection ofconstruction byorunderthe supervision of the licensed design professional responsible for the design should be considered because the person in charge of the design is usually the best qualified to determine if constructionis inconformancewith construction documents. When such an arrangement is not feasible,inspection of construction through other licensed design professionals or through separate inspection organizations with demonstrated capability for performing the inspection may be used.

In some jurisdictions,legislation has established registration orlicensingprocedures for personsperformingcertain inspection functions. A check should be made in the general building code or with the building official to ascertain if any such requirements exist within a specific jurisdiction.

Inspection responsibilityand thedegreeofinspection required should be set forth in the contracts between the owner,architect,engineer,contractor,andinspector. Adequate fees should be provided consistent with the work and equipment necessary to properly perform the inspection

K1.3.2 By inspection, the Code does not mean that the inspector should supervise the construction.Rather, it means that the one employed for inspection should visit the project with the frequency necessary to observe the various stages

)Construction and removal offorms and reshoring: ) Placing of reinforcementandanchors:

1.3.3Whentheambienttemperaturetallsbelow 40For rises above95°F,a record shall bekept of concrete temperatures and of protection given to concreteduringplacementandcuring,

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MANUAL OF CONCRETE PRACTICE

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The Code prescribes minimum requirements for inspection of all structures within its scope. It is not a construction specification and any user of the Code may require higher standards of inspection than cited in the legal code if additional requirements are necessary

R1.3.3Theterm"ambienttemperaturemeansthe temperature of the environment to which the concrete is directly exposed. Concrete temperature as used in this section maybe taken as the surface temperature of the

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设备安装规范1.4Approvalofspecialsystemsof

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concrete.Surface temperatures may be determined by placingtemperaturesensors in contactwithconcrete surfaces or between concrete surfaces and covers used for curing, such as insulation blankets or plastic sheeting.

Ri.3.5 — The purpose of this section is to ensure that the detailing required in special moment frames is properly executed through inspection by personnel who are qualified to do this Work. Qualifications of inspectors should be accept able to the jurisdiction enforcing the general building code.

R1.4Approval of special systems of

For special systems considered under this section, specific tests,load factors,deflection limits,and other pertinent requirements should be set by the board of examiners, and should be consistent with the intent of the Code.

排水管道标准规范范本The provisions of this section do not apply to model tests used to supplement calculations under 1.2.2 or to strength evaluation of existing structures under Chapter 20