1、Designation: C1491 11Standard Specification forConcrete Roof Pavers1This standard is issued under the fixed designation C1491; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indic
2、ates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers concrete roof pavers that aremachine-made from hydraulic cement, water, and suitablemineral aggregates with or without the inclusion of
3、 othermaterials, for use as roof ballast and protection of roofmembranes.NOTE 1The design of roof ballast systems for resisting wind uplift isbeyond the scope of this specification. Building codes and other standardsshould be consulted in designing for wind uplift resistance.1.2 The text of this sta
4、ndard references notes and footnotesthat provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be consideredas requirements of the standard.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are
5、mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety an
6、d health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C33 Specification for Concrete AggregatesC140 Test Methods for Sampling and Testing ConcreteMasonry Units and Related UnitsC150 Specification for Portland CementC331
7、Specification for Lightweight Aggregates for Con-crete Masonry UnitsC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC989 Specification for Slag Cement for Use in Concreteand MortarsC1157 Performance Specificat
8、ion for Hydraulic CementC1209 Terminology of Concrete Masonry Units and Re-lated Units3C1232 Terminology of MasonryC1262 Test Method for Evaluating the Freeze-Thaw Dura-bility of Dry-Cast Segmental Retaining Wall Units andRelated Concrete Units3. Terminology3.1 Terminology defined in Terminology C12
9、09 and Termi-nology C1232 shall apply to this specification.4. Material4.1 Cementitious MaterialsMaterials shall conform to thefollowing applicable specifications:4.1.1 Portland CementSpecification C150.4.1.2 Modified Portland CementPortland cement con-forming to Specification C150, modified as foll
10、ows:4.1.2.1 LimestoneLimestone, with a minimum 85 % cal-cium carbonate (CaCO3) content, shall be permitted to beadded to the cement, provided the requirements of Specifica-tion C150 are modified as follows:(1) Limitation on Insoluble Residue1.5 %.(2) Limitation on Air Content of MortarVolume percent
11、,22 % max.(3) Limitation on Loss on Ignition7 %.4.1.3 Blended CementsCement conforming to eitherSpecification C595 or Specification C1157.4.1.4 PozzolansSpecification C618.4.1.5 Blast Furnace SlagSpecification C989.4.2 AggregatesAggregates shall conform to the followingspecifications, except that gr
12、ading requirements shall notnecessarily apply:4.2.1 Normal Weight AggregatesSpecification C33.4.2.2 Lightweight AggregatesSpecification C331.4.3 Other ConstituentsAir-entraining agents, coloringpigments, integral water repellents, finely ground silica, andother constituents shall be previously estab
13、lished as suitable foruse in concrete roof pavers and shall conform to applicable1This specification is under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and is the direct responsibility of SubcommitteeC15.03 on Concrete Masonry Units and Related Units.Current edition approve
14、d Dec. 1, 2011. Published December 2011. Originallyapproved in 2001. Last previous edition approved in 2009 as C1491 03 (2009).DOI: 10.1520/C1491-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStanda
15、rds volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Driv
16、e, PO Box C700, West Conshohocken, PA 19428-2959, United States.ASTM standards or shall be shown by test or experiencesatisfactory to the purchaser to be not detrimental to thedurability of the units or any material customarily used inconcrete roof pavers.5. Physical Requirements5.1 At the time of d
17、elivery to the work site, the units shallconform to the physical requirements of Table 1 when tested inaccordance with 8.2.5.2 Resistance to Flexural LoadThe average resistance toflexural load for three paver units shall exceed 350 lb (1557 N)and resistance to flexural load of each individual unit s
18、hallexceed 280 lb (1246 N) when tested in accordance with 8.2.5.3 Ballast WeightRequirements for ballast weight perunit area shall be specified separately.5.4 Freeze-Thaw DurabilityIn areas where repeatedfreezing and thawing under saturated conditions occur, freeze-thaw durability shall be demonstra
19、ted by test or by proven fieldperformance that the concrete roof paver units have adequatedurability for the intended use. When testing is required by thespecifier to demonstrate freeze-thaw durability, the units shallbe tested in accordance with 8.3.5.4.1 Specimens shall comply with either of the f
20、ollowing:(1) the weight loss of each of five test specimens at theconclusion of 100 cycles shall not exceed 1 % of its initialweight; or (2) the weight loss of each of four or five testspecimens at the conclusion of 150 cycles shall not exceed1.5 % of its initial weight.NOTE 2This specification does
21、 not include criteria for hail stoneimpact. Where required, these criteria should be specified by the pur-chaser. Appendix X1 is provided as guidance to specifying hail-impactresistance.6. Permissible Variations in Dimension and Weight6.1 Overall dimensions for width, height, and length shallnot dif
22、fer by more than 618 in. (3.2 mm) from the specifiedstandard dimensions.6.2 Ballast weight shall not differ by more than 6 2.0 lb/ft2(9.7 kg/m2) from the specified weight.7. Finish and Appearance7.1 All units shall be sound and free of cracks or otherdefects that would interfere with the proper plac
23、ement of theunit or would significantly impair the strength or permanenceof the construction. Minor cracks incidental to the usualmethod of manufacture or minor chipping resulting fromcustomary methods of handling in shipment and delivery arenot grounds for rejection.7.2 Five percent of the units in
24、 a shipment are permitted tocontain chips not larger than 1 in. (25.4 mm) in any dimension,or cracks not wider than 0.02 in. (0.5 mm) and not longer than25 % of the nominal height of the unit.8. Sampling and Testing8.1 The purchaser or authorized representative shall beaccorded proper facilities to
25、inspect and sample the units at theplace of manufacture from the lots ready for delivery.8.2 Sample and test units for compressive strength, flexuralload, absorption, density, ballast weight, and dimensionaltolerance in accordance with Test Methods C140.8.3 When required, sample and test five specim
26、ens forfreeze-thaw durability in water in accordance with Test MethodC1262. Freeze-thaw durability shall be based on tests of unitsmade with the same materials, concrete mix design, manufac-turing process, and curing method, conducted not more than 24months prior to delivery.9. Compliance9.1 If a sa
27、mple falls to conform to the specified require-ments, the manufacturer shall be permitted to remove unitsfrom the shipment. A new sample shall be selected by thepurchaser from remaining units from the shipment with asimilar configuration and dimension and tested at the expenseof the manufacturer. If
28、 the second sample meets the specifiedrequirements, the remaining portion of the shipment repre-sented by the sample meets the specified requirements. If thesecond sample fails to meet the specified requirements, theremaining portion of the shipment represented by the samplefails to meet the specifi
29、ed requirements.NOTE 3Unless otherwise specified in the purchase order, the cost oftests is typically borne as follows: (1) If the results of the tests show thatthe units do not conform to the requirements of this specification, the costis typically borne by the seller. (2) If the results of the tes
30、ts show that theunits conform to the specification requirements, the cost is typically borneby the purchaser.10. Keywords10.1 absorption; aggregates; ballast weight; cementitious;compressive strength; concrete roof pavers; durability; lime-stone; portland cementTABLE 1 Physical RequirementsDensity C
31、lassification Oven-Dry Densityof Concretelb/ft3(kg/m3)Maximum WaterAbsorption,lb/ft3(kg/m3)Minimum Net AreaCompressive Strength,lb/in.2(MPa)Average of 3 units Average of 3 units Individual Unit Average of 3 units Individual UnitLightweight 95 (1522) or less 15 (240) 17 (272) 3000 (20.7) 2600 (17.9)M
32、edium Weight Over 95 to 115(1522 to 1842)13 (208) 15 (240) 3000 (20.7) 2600 (17.9)Normal Weight Over 115 (1842) 10 (160) 12 (192) 3000 (20.7) 2600 (17.9)C1491 112APPENDIX(Nonmandatory Information)X1. SPECIFYING RESISTANCE TO HAIL STONE IMPACTX1.1 Where the purchasers deign criteria include resis-tan
33、ce to impact from hail, hailstorm activity can be estimatedfrom Fig. X1.1. As further guidance, a minimum energy-impact resistance to hail stones in areas potentially subjected tomoderate to heavy hailstorm activity shall be 15 ft-lb (20.3 J).This impact energy is related to a hail stone of approxim
34、atediameter of 1.83 in. (46.5 mm), having a density 90 % of thatof water, and falling at the terminal velocity for a sphericalshape. Fig. X1.1 is based on hail storm activity reported by theNational Weather Service for the time period between 1955and 1995 and includes all reported hail storms with a
35、veragehail stone diameter 1.8 in. (45.7 mm) or larger.X1.2 Recommended testing for hail stone impact resistanceentails impacting three specimens, supported as they would bein use, each to a series of three blows from a spherical ice ballof a size, configuration, and impact energy as outlined above.F
36、ailure of any specimen would be defined as the completefracturing of the test specimen through the height of the paver.(Dents, chips, or cracks shall not be considered as failure of thetest specimen.)C1491 113SUMMARY OF CHANGESCommittee C15 has identified the location of selected changes to this sta
37、ndard since the last issue(C1491 03 (2009) that may impact the use of this standard. (Approved Dec. 1, 2011.)(1) Revised Table 1 to add individual unit absorption resultsand to include compressive strength results in this table.ASTM International takes no position respecting the validity of any pate
38、nt rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision
39、at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comme
40、nts will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted
41、 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).FIG. X1.1 Hail Storm FrequencyC1491 114
