1、Designation: C1491 11C1491 13Standard 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 parenthes
2、es indicates 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 are machine-made from hydraulic cement, water, and suitable mineralaggregates with or without the inc
3、lusion of other materials, for use as roof ballast and protection of roof membranes.NOTE 1The design of roof ballast systems for resisting wind uplift is beyond the scope of this specification. Building codes and other standards shouldbe consulted in designing for wind uplift resistance.1.2 The text
4、 of this standard references notes and footnotes that provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be considered as requirements of the standard.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in p
5、arentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appro
6、priate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C33 Specification for Concrete AggregatesC140 Test Methods for Sampling and Testing Concrete Masonry Units and Related UnitsC150 Specification for Portl
7、and CementC331 Specification for Lightweight Aggregates for Concrete Masonry UnitsC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in ConcreteC989 Specification for Slag Cement for Use in Concrete and MortarsC1157 Perfor
8、mance Specification for Hydraulic CementC1209 Terminology of Concrete Masonry Units and Related Units (Withdrawn 2009)3C1232 Terminology of MasonryC1262 Test Method for Evaluating the Freeze-Thaw Durability of Dry-Cast Segmental Retaining Wall Units and RelatedConcrete Units3. Terminology3.1 Termino
9、logy defined in Terminology C1209 and Terminology C1232 shall apply to this specification.4. Material4.1 Cementitious MaterialsMaterials shall conform to the following applicable specifications:4.1.1 Portland CementSpecification C150.4.1.2 Modified Portland CementPortland cement conforming to Specif
10、ication C150, modified as follows:1 This specification is under the jurisdiction of ASTM Committee C15 on Manufactured Masonry Units and is the direct responsibility of Subcommittee C15.03 onConcrete Masonry Units and Related Units.Current edition approved Dec. 1, 2011Dec. 1, 2013. Published Decembe
11、r 2011December 2013. Originally approved in 2001. Last previous edition approved in 20092011as C1491 03C1491 11. (2009). DOI: 10.1520/C1491-11.10.1520/C1491-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of
12、ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of
13、 what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered
14、 the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.1.2.1 LimestoneLimestone, with a minimum 85 % calcium carbonate (CaCO3) content, shall be permit
15、ted to be added to thecement, provided the requirements of Specification C150 are modified as follows:(1) Limitation on Insoluble Residue1.5 %.(2) Limitation on Air Content of MortarVolume percent, 22 % max.(3) Limitation on Loss on Ignition7 %.4.1.3 Blended CementsCement conforming to either Specif
16、ication C595 or Specification C1157.4.1.4 PozzolansSpecification C618.4.1.5 Blast Furnace SlagSpecification C989.4.2 AggregatesAggregates shall conform to the following specifications, except that grading requirements shall notnecessarily apply:4.2.1 Normal Weight AggregatesSpecification C33.4.2.2 L
17、ightweight AggregatesSpecification C331.4.3 Other ConstituentsAir-entraining agents, coloring pigments, integral water repellents, finely ground silica, and otherconstituents shall be previously established as suitable for use in concrete roof pavers and shall conform to applicable ASTMstandards or
18、shall be shown by test or experience satisfactory to the purchaser to be not detrimental to the durability of the unitsor any material customarily used in concrete roof pavers.5. Physical Requirements5.1 At the time of delivery to the work site, the units shall conform to the physical requirements o
19、f Table 1 when tested inaccordance with 8.2.5.2 Resistance to Flexural LoadThe average resistance to flexural load for three paver units shall exceed 350 lb (1557 N) andresistance to flexural load of each individual unit shall exceed 280 lb (1246 N) when tested in accordance with 8.2.5.3 Ballast Wei
20、ghtRequirements for ballast weight per unit area shall be specified separately.5.4 Freeze-Thaw DurabilityIn areas where repeated freezing and thawing under saturated conditions occur, freeze-thawdurability shall be demonstrated by test or by proven field performance that the concrete roof paver unit
21、s have adequate durabilityfor the intended use. When testing is required by the specifier to demonstrate freeze-thaw durability, the units shall be tested inaccordance with 8.3.5.4.1 Specimens shall comply with either of the following: (1) the weight loss of each of five test specimens at the conclu
22、sionof 100 cycles shall not exceed 1 % of its initial weight; or (2) the weight loss of each of four or five test specimens at the conclusionof 150 cycles shall not exceed 1.5 % of its initial weight.NOTE 2This specification does not include criteria for hail stone impact. Where required, these crit
23、eria should be specified by the purchaser. AppendixX1 is provided as guidance to specifying hail-impact resistance.6. Permissible Variations in Dimension and Weight6.1 Overall dimensions for width, height, and length shall not differ by more than 618 in. (3.2 mm) from the specified standarddimension
24、s.6.2 Ballast weight shall not differ by more than 6 2.0 62.0 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 other defects that would interfere with the proper placement of the unit orwould significantly impair the strength or
25、permanence of the construction. Minor cracks incidental to the usual method ofmanufacture or minor chipping resulting from customary methods of handling in shipment and delivery are not grounds forrejection.7.2 Five percent of the units in a shipment are permitted to contain chips not larger than 1
26、in. (25.4 mm) in any dimension, orcracks not wider than 0.02 in. (0.5 mm) and not longer than 25 % of the nominal height of the unit.TABLE 1 Physical RequirementsDensity Classification Oven-Dry Densityof Concretelb/ft3 (kg/m3)Maximum WaterAbsorption,lb/ft3 (kg/m3)Minimum Net AreaCompressive Strength
27、,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)Medium 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 (1
28、92) 3000 (20.7) 2600 (17.9)C1491 1327.3 A shipment shall not contain more than 5% of units, including broken units, that do not meet the requirements of 6.1 and7.2.8. Sampling and Testing8.1 The purchaser or authorized representative shall be accorded proper facilities to inspect and sample the unit
29、s at the placeof manufacture from the lots ready for delivery.8.2 Sample and test units for compressive strength, flexural load, absorption, density, ballast weight, and dimensional tolerancein accordance with Test Methods C140.8.3 When required, sample and test five specimens for freeze-thaw durabi
30、lity in water in accordance with Test Method C1262.Freeze-thaw durability shall be based on tests of units made with the same materials, concrete mix design, manufacturing process,and curing method, conducted not more than 24 months prior to delivery.9. Compliance9.1 If a sample falls to conform to
31、the specified requirements, the manufacturer shall be permitted to remove units from theshipment. A new sample shall be selected by the purchaser from remaining units from the shipment with a similar configurationand dimension and tested at the expense of the manufacturer. If the second sample meets
32、 the specified requirements, the remainingportion of the shipment represented by the sample meets the specified requirements. If the second sample fails to meet the specifiedrequirements, the remaining portion of the shipment represented by the sample fails to meet the specified requirements.NOTE 3U
33、nless otherwise specified in the purchase order, the cost of tests is typically borne as follows: (1) If the results of the tests show that theunits do not conform to the requirements of this specification, the cost is typically borne by the seller. (2) If the results of the tests show that the unit
34、sconform to the specification requirements, the cost is typically borne by the purchaser.10. Keywords10.1 absorption; aggregates; ballast weight; cementitious; compressive strength; concrete roof pavers; durability; limestone;portland cementAPPENDIX(Nonmandatory Information)X1. SPECIFYING RESISTANCE
35、 TO HAIL STONE IMPACTX1.1 Where the purchasers deign criteria include resistance to impact from hail, hailstorm activity can be estimated from Fig.X1.1. As further guidance, a minimum energy-impact resistance to hail stones in areas potentially subjected to moderate to heavyhailstorm activity shall
36、be 15 ft-lb (20.3 J). This impact energy is related to a hail stone of approximate diameter of 1.83 in. (46.5mm), having a density 90 % of that of water, and falling at the terminal velocity for a spherical shape. Fig. X1.1 is based on hailstorm activity reported by the National Weather Service for
37、the time period between 1955 and 1995 and includes all reported hailstorms with average hail stone diameter 1.8 in. (45.7 mm) or larger.X1.2 Recommended testing for hail stone impact resistance entails impacting three specimens, supported as they would be in use,each to a series of three blows from
38、a spherical ice ball of a size, configuration, and impact energy as outlined above. Failure ofany specimen would be defined as the complete fracturing of the test specimen through the height of the paver. (Dents, chips, orcracks shall not be considered as failure of the test specimen.)C1491 133SUMMA
39、RY OF CHANGESCommittee C15 has identified the location of selected changes to this standard since the last issue (C1491 03(2009)C1491 11) that may impact the use of this standard. (Approved(December Dec. 1, 2011.)1, 2013)(1) RevisedAdded Table 17.3 to add individual unit absorption results and to in
40、clude compressive strength results in this table.,limiting units not complying with various requirements of the standard to 5 %.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are
41、 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 at any time by the responsible technical committee and must be reviewed every five years andif not r
42、evised, 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 comments will receive careful consideration at a meeting of theresponsible technical committee, which you
43、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 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United S
44、tates. 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 134
