1、Designation: C 1560 03Standard Test Method forHot Water Accelerated Aging of Glass-Fiber ReinforcedCement-Based Composites1This standard is issued under the fixed designation C 1560; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method provides a way of accelerating theaging of glass fiber reinforced cementitious composite
3、s inorder to develop data that will indicate real-life naturalweathering performance.1.2 The coupons prepared for this test method will be testedusing Test Method C 947.1.3 This test method can be used to age coupons for othertest methods.1.4 This standard does not purport to address all of thesafet
4、y concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:C 947 Test Method for Flexural Pro
5、perties of Thin SectionGlass-Fiber Reinforced Concrete (Using Simple BeamWith Third-Point Loading)2C 1228 Practice for Preparing Coupons for Flexural andWash-out Tests on Glass-Fiber Reinforced Concrete23. Significance and Use3.1 The basis for this test as an indicator of the long termbehavior of fi
6、ber reinforced composites is that elevated tem-perature and moisture content accelerate the formation of theproducts of hydration of the cement in the matrix, particularlycalcium hydroxide.3.1.1 It is known that the interaction of these products ofhydration, particularly calcium hydroxide, with the
7、fibers canhave a major effect on the long-term properties of the compos-ites.3.1.2 The principal mechanism that occurs is that thecalcium hydroxide forms within the bundles of filaments thatform the glass fiber strand. This gradually bonds the filamentstogether, which reduces filament pull-out. This
8、 causes a reduc-tion in the strain capacity of the composite, thereby reducingthe strength of the composite and changing the composite froma ductile material to an increasingly brittle material.3.1.3 Accelerating the formation of the hydration productsaccelerates their interaction with the fibers, h
9、ence acceleratingthe aging of the composite.3.2 The data developed from this test are used by research-ers and manufacturers to evaluate the long-term performanceof different mixtures, reinforcements, mixture components, andto provide data for the development of design procedures forproducts made fr
10、om these composites.3.2.1 The recorded data also provides screening informationas new matrices and reinforcements are developed.3.3 The usefulness of the test as an indicator of long termcomposite performance is valid if the only reactions that areaccelerated are those that occur more slowly under n
11、aturalweathering, hot water can induce effects in some composites,for instance those containing acrylic polymer, that may notoccur in natural weathering. This test method may not be avalid indicator of long-term performance of such composites.4. Apparatus4.1 Aging TanksTank material can be but not l
12、imited to,plastic, insulated to maintain a stable temperature. Insulationshould cover all exterior surfaces including the cover. Insula-tion can be a foam product as used in building construction.4.1.1 The size of the tank is typically 12 in. deep (300 mm),18 in. wide (450 mm), and 20 to 36 in. (600
13、 to 900 mm), inlength. Size is determined by the amount of coupons to beprocessed and the ability to maintain stable temperatures.Water temperature in several medium sized tanks is easier tocontrol than one large tank.4.2 Heating UnitAn immersion unit with rheostat forcontrolling temperature, such a
14、s those used for aquariums, hasbeen found to be satisfactory.4.3 ThermometerA standard immersion, laboratory ther-mometer is used to monitor temperature. More sophisticatedrecorders can also be used.1This test method is under the jurisdiction of ASTM Committee C27 on PrecastConcrete Products and is
15、the direct responsibility of Subcommittee C27.40 on GlassFiber Reinforced Concrete Made by the Spray-Up Process .Current edition approved Feb. 10, 2003. Published July 2003.2Annual Book of ASTM Standards, Vol 04.05.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
16、 PA 19428-2959, United States.4.4 Immersion RackA rack built from a non-contaminating material, such as wood or plastic, should beused to maintain coupon separation. Space should be at least 1in. (25 mm) between coupons and coupons should be totallyimmersed. The design of the rack is left up to the
17、testingfacility.4.5 It is recommended that about 50 in.3(820 cc) of waterbe used per coupon.4.6 The tank should be sealed to prevent loss of waterthrough evaporation.5. Procedure5.1 Coupons are prepared according to Practice C 1228, orcut from actual product, and coded for identification. Couponsare
18、 first cured for 28 days and tested using Test Method C 947.A random sampling of test coupons is tested to establishunaged or beginning properties. Sufficient coupons should beproduced to allow the testing of a minimum of six coupons perinterval.5.1.1 Coupons cut from actual product should have apro
19、duct history if possible.5.2 Coupons are totally immersed in the tank filled withpreheated water. The type of water, for example. distilled,lime-saturated, etc., must be chosen to minimize contaminationof the coupons and to minimize the possibility of the waterdissolving constituents of the composit
20、e that could affect theaging process.5.2.1 Different matrices should be aged in separate tanks.5.2.2 It is important that the water not be changed during theduration of the test. Also topping up should be minimal.5.3 Test intervals after immersion are: 0, 5, 10, 20, 30, 40,50, 60, 70, 80, 90 or more
21、 days. Aging can be considered ascomplete when the doubling of the aging period shows lessthan a 5 % decrease in the flexural ultimate and/or a decreaseof strain capacity of less than 10 %.5.4 Water temperature can be 122F (50C) up to 176F(80C) but must be stable at the chosen temperature. Aging wil
22、lbe faster at higher temperatures. Temperature should be main-tained at the required level 6 3F (2C) and measured andrecorded at twelve hour intervals. Manual checks with alaboratory thermometer is satisfactory, however the use of acontinuous recorder is preferred. If the temperature increasesor dec
23、reases more than 3F (2C) from the chosen value and isconstant for over five hours the test should be discontinued. Ifthere is any question regarding the stability of the temperaturethe test should be discontinued.5.5 At each test interval, aged coupons should be selected atrandom from the remaining
24、coupons in the tank and tested.6. Calculation or Interpretation of Results6.1 Modulus of Rupture is calculated in accordance withTest Method C 947.6.2 Strain to failure is measured analogously using themeasured deflection at failure.7. Report7.1 The report shall include the following:7.1.1 Identific
25、ation of coupon,7.1.2 Description of coupon,7.1.3 Temperature of water,7.1.4 Number of hours immersed,7.1.5 Date and time of test,7.1.6 Type of test performed,7.1.7 Flexural yield strength and flexural ultimate strengthas per Test Method C 947,7.1.8 Measured deflection at failure,7.1.9 Appearance of
26、 coupon at rupture point,7.1.10 Description of reinforcement,7.1.11 Description of mix proportions including fiber con-tent,7.1.12 Type of aging medium, for example, distilled water,lime saturated water, etc., and7.1.13 Source of coupons.8. Precision and Bias8.1 The precision and bias criteria are b
27、eing developed andtests are being conducted.9. Keywords9.1 accelerated aging; GFRC; glass fiber; glass fiber rein-forced concreteASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard ar
28、e 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
29、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 comments will receive careful consideration at a meeting of theresponsible technical committee, which yo
30、u 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 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).C1560032
