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本文(UFC 3-250-04 CHANGE 2-2009 STANDARD PRACTICE FOR CONCRETE PAVEMENTS [Superseded ARMY ARMY TM 5-822-7].pdf)为本站会员(roleaisle130)主动上传,麦多课文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知麦多课文库(发送邮件至master@mydoc123.com或直接QQ联系客服),我们立即给予删除!

UFC 3-250-04 CHANGE 2-2009 STANDARD PRACTICE FOR CONCRETE PAVEMENTS [Superseded ARMY ARMY TM 5-822-7].pdf

1、 UFC 3-250-04 16 January 2004 including Change 2 - 29 July 2009UNIFIED FACILITIES CRITERIA (UFC) STANDARD PRACTICE FOR CONCRETE PAVEMENTS APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-UFC 3-250-04

2、16 January 2004including Change 2 - 29 July 2009 1 UNIFIED FACILITIES CRITERIA (UFC) DESIGN: STANDARD PRACTICE FOR CONCRETE PAVEMENTS Any copyrighted material included in this UFC is identified at its point of use. Use of the copyrighted material apart from this UFC must have the permission of the c

3、opyright holder. U.S. ARMY CORPS OF ENGINEERS (Preparing Activity) AIR FORCE CIVIL ENGINEER SUPPORT AGENCY Record of Changes (changes are indicated by 1 . /1/) Change No. Date Location 2 29 July 2009 Removed FA designation to indicate unification This UFC supersedes TM 5-822-7, dated 16 August 1987

4、2and UFC 3-250-12N dated 8 June 2005/2/. The format of this UFC does not conform to UFC 1-300-01; however, the format will be adjusted to conform at the next revision. The body of this UFC is the previous TM 5-822-7, dated 16 August 1987. Provided by IHSNot for ResaleNo reproduction or networking pe

5、rmitted without license from IHS-,-,-UFC 3-250-04 16 January 2004 2FOREWORD including Change 2 - 29 July 20091 The Unified Facilities Criteria (UFC) system is prescribed by MIL-STD 3007 and provides planning, design, construction, sustainment, restoration, and modernization criteria, and applies to

6、the Military Departments, the Defense Agencies, and the DoD Field Activities in accordance with USD(AT DESIGN AND CONSTRUCTION12345678910111213141516171819202122232425111341111121212131313151517202123232424242727A-1B-1C-1D-1iProvided by IHSNot for ResaleNo reproduction or networking permitted withou

7、t license from IHS-,-,-Figure 1.2.3.D-1.D-2.D-3.D-4.D-5.Table 1.2.3.4.5.6.7.8.C-1.C-2.D-1.LIST OF FIGURESPrediction of concrete rate of evaporation.Air Force runway grooving requirements.Special joint between new and existing pavement.Typical layout for RCCP test section.Compaction of first paving l

8、ane.Compaction of interior paving lanes.Construction of a cold joint.Two-lift cold joint preparation.LIST OF TABLESApproximate relation between water-cement ratio and strengths of concreteCoarse aggregate size groupsGrading of coarse aggregateDeleterious materials in coarse aggregates for airfield a

9、nd heliport pavementsDeleterious materials in coarse aggregates for other pavementsGrading of fine aggregateDeleterious substances in fine aggregateSurface smoothness - airfield and heliport pavementsSelected characteristics of fiber-reinforced airfield pavementsInterim suggested maximum joint spaci

10、ng for steel-fiber-reinforced concreteVibratory rollers used in RCCP constructionProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STANDARD PRACTICE FOR CONCRETE PAVEMENTS1. Purpose. This manual provides information on thematerials and construction pro

11、cedures for concretepavements.2. Scope. This manual describes the constituents tobe used in concrete, the procedures to be used inmanufacturing concrete, and the equipment andprocedures to place, texture, and cure concrete forpavements.3.Responsibilities, strength, and air content.a. Responsibility

12、for mixture proportioning. Theresponsibility for mixture proportioning must beclearly assigned to either the contractor or thecontracting officer in the project specifications.When the contracting officer is responsible formixture proportioning, he will approve all concretematerials as well as deter

13、mine and adjust propor-tions of all concrete mixtures as necessary to obtainthe strength and quality of concrete required for thepavements. Cement will be a separate pay item inthe contract. When the contractor is responsible formixture proportioning, he will control all proportionsof the concrete m

14、ixture necessary to obtain thestrength and quality of the concrete required for thepavements, and cement will not be a separate payitem in the contract. However, the contracting officeris responsible for approving the quality of allmaterials the contractor uses in the concrete.b. Approval responsibi

15、lity. The contracting officeris responsible for approval of all materials, mixtureproportions, plants, construction equipment, andconstruction procedures proposed for use by thecontractor. The contractor must submit proposedmixtures if he is responsible for mixture propor-tioning; samples of all mat

16、erials; and detaileddescriptions of all plants, construction equipment,and proposed construction procedures prior to thestart of construction.c. Flexural strength. Structural designs are basedon flexural strengths that the concrete is expectedto obtain at 28 days for road pavements and 90 daysfor ai

17、rfield pavements. These ages are not adequatefor quality control in the field since a large amountof low-strength concrete could be placed beforestrength tests on samples revealed the problem.Correlations can be established between a 14-daystrength and the 28- or 90day strength used indesign, and th

18、is correlated 14-day strength can beused as a strength check for a more timely concretemixture control in the field.(l.) Materials and flexural strength. To selectsuitable flexural strengths for the design ofpavements and for inclusion in contract specifica-tions, the contracting officer should have

19、 reliableinformation regarding flexural strengths obtainablewith acceptable concrete materials which are availablein the vicinity of the project. Typical design valuesfor flexural strength of paving-quality concretevary from 500 to 750 pounds per square inch (psi).Numerous tests indicate considerabl

20、e variation inthe flexural strength of concrete when differentaggregates or different cements are used. There aresome indications that aggregate shape and modulusof elasticity are relatively more important inconcrete flexural strength than in compressivestrength. Also, after optimum flexural strengt

21、h isreached, there usually is little increase in strength,even with a large increase in cement content. Mixtureproportioning studies will be made in accordancewith ACI 211.1 (see app A for referenced publications)to determine the flexural strengths to be used forthe design of the project. The water-

22、cement ratio-strength relations for mixture proportioning in ACI211.1 are given in terms of compressive strength.Table 1 gives some approximate guidance forrelating the concrete modulus of rupture to thecompressive strength-water cement ratio relation-ships given in ACI 211.1. All aggregates, cement

23、itiousmaterials, and admixtures used in the mixtureproportioning studies will be representative ofmaterials available for use in pavement construction.In selecting a flexural strength for pavement design,suitable allowance will be made for variations instrength indicated by tests of different combin

24、a-tions of aggregate and cement. Pavement designwill be based on a realistic and economical strengthobtainable with available materials.1Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Table 1. Approximate relation between water-cement ratio and stre

25、ngths of concrete (modified from ACI 211.1)(eq 1)Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TM 5-822-7/AFM 88-6, Chap. 8characteristics of freshly mixed concrete and isrequired for the freezing and thawing resistance ofhardened concrete. The use

26、 of entrained air inconcrete will reduce strength, but because of theimproved workability in the freshly mixed concrete,adjustments in aggregate proportions and reductionof water are normally possible that will negate or atleast minimize the loss of strength. Proper propor-tioning and control of the

27、 air-entrained concretemixture are essential in order to derive maximumbenefits from improvement in the placability anddurability of concrete with a minimum effect onflexural strength.(2.) Percentage of air content. The specified aircontent will be 6 1 percent for concretepavements located in region

28、s where resistance tofreezing and thawing is a prime consideration, andwill be 5 1 percent for concrete pavementslocated in regions where frost action is not a factorand air entrainment is used primarily to improve theworkability and placability of freshly mixed concrete.Air content will be controll

29、ed in the field at the pointwithin the specified range most appropriate for localconditions depending upon the severity of exposureand the quality and maximum size of aggregate. Ifslag aggregate is used, the air content will be deter-mined by the volumetric method as described inASTM C 173. Where th

30、e aggregate is of compara-tively poor quality or when the maximum size is 1%inches or less, the air content will be controlled at 6 1 percent. In such instances, where resistance tofreezing and thawing is not a prime consideration,the air content will be 5 1 percent. If furtherreduction in the air c

31、ontent or the use of non-air-entrained concrete is necessary, prior approval willbe obtained from HQDA (DAEN-ECE-G), Wash-ington, DC 20314-1000 or the appropriate Air Forcemajor command.e. Cement content. Either the contractor or thecontracting officer may be responsible for mixtureproportioning. Wh

32、en the contractor is responsiblefor mixture proportioning, no separate payment willbe made for cement. When the contracting officer isresponsible for mixture proportioning, no limits forthe quantity of cement content will be included inthe contract specifications; the quantity of cementused per cubi

33、c yard of concrete will be determinedby the contracting officer, and cement will be paidfor under a separate bid item. When the concreteproposed for use on a paving project has a cementcontent of less than 470 pounds per cubic yard, priorapproval will be obtained from HQDA (DAEN-ECE-G) or the approp

34、riate Air Force major command.When concrete proportioning is the responsibility ofthe contractor and the cement content is less than470 pounds per cubic yard, the results should beverified by two Corps of Engineers Divisionlaboratories or commercial laboratories prior tosubmittal. The results of mix

35、ture proportioningstudies for proposed aggregates and cements andthe results of qualitative tests on aggregates and onresulting concretes will be submitted with requestsfor approval.4. Cement.a. Five portland cements designated as Types Ithrough V are marketed today. ASTM C 150 providesa detailed sp

36、ecification for these cements. Type Iportland cement is common or ordinary cement thatis supplied unless another type is specified. Type IIis modified portland cement that provides moderateresistance against sulfate attack and a lower heat ofhydration than Type I cement. It is common forcement to be

37、 manufactured to meet the physical andchemical requirements of both Type I and II cements.b. Type III cement is high early-strength cement.Ultimate strength is about the same as Type Icement, but Type III cement has a 3-day compressivestrength approximately equal to the Type Icements 7-day strength.

38、 The cost of Type IIIcement in lieu of Types I or II cement can only bejustified when early strength gain is needed to openpavements to traffic or the high heat of hydration isneeded for cool construction periods. Type IVcement has a low heat of hydration that may beuseful in mass concrete but is no

39、t likely to beencountered in pavement construction. Type Vsulfate-resistant cement should be used when theconcrete will be exposed to severe sulfate attack.The potential for severe sulfate attack exists whenthe concrete is exposed to water-soluble sulfate insoil or water in excess of 0.20 percent or

40、 1,500 partsper million. The potential for moderate sulfateattack exists for sulfate contents in excess of 0.10,or 150 parts per million.c. High alumina cement, also known as aluminousor calcium aluminate cement, gains most of itsstrength in one day, has a high exotherm, is resistantto chemical atta

41、ck, and is a refractory material.When exposed to warm, moist conditions, it willundergo a long-term strength loss. High aluminacement may find some specialized applications inpavement construction where its rapid strengthgain, high exotherm, or refractory properties3Provided by IHSNot for ResaleNo r

42、eproduction or networking permitted without license from IHS-,-,-TM 5-822-7/AFM 88-6, Chap. 8outweigh its cost and long-term strength loss.d. There are also some expansive cements,designated as Types K, M, and S in ASTM C 845,that may find some application where concreteshrinkage needs to be minimiz

43、ed or avoided.However, there is little experience with thesecements, and they will require careful investigationbefore use in pavement construction.e. At least one United States manufacturer isactively promoting a slag cement made by grindingiron blast furnace slag. This may be substituted forup to

44、50 percent of the portland cement in a pavementmixture if tests show the required final propertiesare achieved in the hardened concrete. Preblendedmixes of portland-pozzolan (Type IP), and portland-slag cements (Type IS) are described in ASTM C 595and are acceptable for use in pavements.5. Aggregate

45、s.a. Approval of aggregates. The contractor will useaggregates from approved sources. If the contractorproposes to use aggregates from an unapprovedsource, the Government will be responsible forconducting tests to determine whether the proposedaggregates will meet the requirements of the project.Sam

46、pling and aggregate delivery costs will be borneby the contractor. The contract specifications willstate aggregate sample size, delivery location, andrequired evaluation time for the proposed aggre-gates. For small jobs requiring 1,600 cubic yards orless of concrete, all tests for aggregates from an

47、unapproved source will be done by the contractor.b. Quality. Aggregates must generally meet therequirements of ASTM C 33, as modified in thefollowing paragraphs. These requirements can beadjusted as necessary to reflect local experiencewith specific aggregates to insure economical use ofaggregates t

48、o meet project requirements. Themagnesium or sulfate soundness test (ASTM C 88)required in ASTM C 33 has not been consistentlysuccessful in identifying frost-resistant aggregate.Consequently, if an otherwise suitable aggregatefails this test, it should be further investigatedusing freezing and thawi

49、ng tests as described inASTM C 666 or ASTM C 682 before it is finallyrejected. Similarly, if an otherwise suitable aggre-gate fails the Los Angeles (LA) abrasion test(ASTM C 131 or C 535), it can be accepted if it has ahistory of local use showing that it can be processedwithout unacceptable degradation and that it isdurable under weathering and traf

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