Active Standard ASTM D3752 | Developed by Subcommittee: C17.03
Book of Standards Volume: 04.05
Historical (view previous versions of standard)
Significance and Use
This procedure facilitates the comparison of different types or grades of asbestos based on their contribution to the flexural modulus of rupture; that is, the reinforcing value, which is considered the most pertinent property for the manufacture of asbestos-cement products.
This test method is primarily intended for fiber grades used normally in asbestos-cement products (Group 6 to Group 4 fibers). Longer fibers (Group 3) or shorter fibers (Group 7) may present difficulties during the preparation of the filter cake because of poor dispersion and uneven settling.
1.1 This test method covers the measurement, on a laboratory scale, of the contribution of asbestos fibers to the strength of asbestos-cement products. The results obtained are used in the primary assessment of different fiber grades prior to their application on a larger scale.
1.2 This test method covers the determination of the modulus of rupture (MR), adjusted to a dry density of 1.60 Mg/m3 (MR A), of asbestos-cement test specimens that contain the asbestos fiber to be evaluated at a concentration of 10 mass %, whereby the degree of fiberization of that fiber is specified in terms of specific surface area as determined by Test Method D2752. The relative reinforcing value of the fiber under test is established by comparison with MRA values obtained with a fiber of known characteristics at a fiber concentration of 10 % and a dry density of 1.60 Mg/m3 (1.60 g/cm3).
Note 1—The adjusted modulus of rupture (MRA) at any intermediate fiber concentration may be interpolated from results suitably determined over a limited spanning range of fiber concentrations. For example, the MRA at 10 % fiber concentration may be graphically determined from data at 3 and 17 %.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 Warning—Breathing of asbestos dust is hazardous. Asbestos and asbestos products present demonstrated health risks for users and for those with whom they come into contact. In addition to other precautions, when working with asbestos-cement products, minimize the dust that results. For information on the safe use of chrysotile asbestos, refer to “Safe Use of Chrysotile: A Manual on Preventive and Control Measures.”
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
C150 Specification for Portland Cement
C184 Test Method for Fineness of Hydraulic Cement by the 150-m (No. 100) and 75-m (No. 200) Sieves
C204 Test Methods for Fineness of Hydraulic Cement by Air-Permeability Apparatus
D1193 Specification for Reagent Water
D2589 Test Method for McNett Wet Classification of Dual Asbestos Fiber
D2590 Test Method for Sampling Chrysotile Asbestos
D2752 Test Methods for Air Permeability of Asbestos Fibers
D2946 Terminology for Asbestos and Asbestos-Cement Products
D3879 Test Method for Sampling Amphibole Asbestos
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
ICS Number Code 91.100.40 (Products in fibre-reinforced cement)