AASHTO M171 pdf free download

AASHTO-M-171 pdf free download.Sheet Materials for Curing Concrete.
1. Scope
1.1 This specification covers materials in sheet form used for covering the surfaces of hydraulic cement concrete to inhibit moisture loss during the curing period and, in the case of the white reflective type materials, to also reduce temperature rise in concrete exposed to radiation from the sun. The following types arc included:
I . 1. 1 Curing Paper:
1.1.1.1 Regular.
1.1.1.2 White.
1 .1.2 Pohethvlene Film:
1.1.2.1 Clear,
1.1.2.2 While Opaque.
1.1.3 Whiie-Bur1ap-PoIvethvlew Sheer.
1.2 The values stated in SI units are to be regarded as the standard. Inch-pound units are provided in parentheses for information only.
Nni I—Tht sdtication dues no4 o’cr materials sue.h as burlap. cotton mars, iw mg’ uscd with additional applications of waler In maintain a water-saturated cnvitonmcnl on such surfaces. Procedures employing these niatenals are discussed in ACI 3OR. Sheet materials having additional characteristics such as insulating prnpcrtics and the ability to carry additional water to the curing region are comnler.iaIly awailable but arc not cumnily addressed in this specification.
1.3 The text of this standard references notes and footnotes which provide explanawry material. These notes and footnotes shall not be considered as requirements of the standard.
3. Terminology
3.1 Dc’Jiniiions:
3.1.1 curing paper. n—a composite consisting of two layers of krall paper bonded together with a bituminous material and reinforced with fiber, used for covering the surface of fresh concrete to inhibit moisture loss during the curing period.
4. Ordering Information
4.1 The purchascr shall spccify the type of’ curing matcrial to be furnished under this specilication.
4.2 Lengths and widths of the rolls or mats of the sheet materials furnished shall be as agreed upon between the purchaser and seller.
5. Performance Requirements
5.1 The sheet materials furnished under this specihcation shall be tough. strong, resilient., and capable of withstanding normal job use without puncturing or tearing.
5.2 The sheet material shall exhibit a water vapor transmission rate (WVTR) of no more than 10 g/m2 in 24 h when tested according to Procedure E of Test Methods E 96.
5.3 The daylight refleance of the white side of white curing paper shall be at least 50 % when measured by Test Method E 1347. The daylight reflectance of white polyethylene film and the polyethylene side of white burlap-polyethylene sheet shall be at least 70 Cjf when measured according to Test Method E 1347.
Non 2—Daylight reflectance is total luminous reflectance factor. C’IE tristimulus value Y for the CIE 1931 (2°) standard observer and CIE stagidard ilLuniinaiit C or D65.
6.2.2 The impact resistance and mechanical properties shall be as required in Specification D 4397.
6.3 White Rurkip-Polverhvkne Sheethi,ç shall consist of burlap weighing not less than 305 g/m2(9 07./yd2) eXtrusion coated on one side with white opaque polyethylene at least 0.10 mm (0.OI in.) thick and meeting the other requirements of 6.2. Thc polyethylene material shall be securely bonded to the burlap so that there will be no separation of the materials during handling and curing of the concrete.
7. Sampling
7.1 Samples of film or sheeting sufficient to determine conformance with this specification shall be taken at random.
8. Keywords
8.1 concrete curing materials; polyethylene film; sheet material for curing concrete; curing paper; white burlap- polyethylene sheetAASHTO-M-171 pdf download.