ASTM C1557 PDF

Meztikus It is th thee res espo pons nsib ibil ility ity of th thee us user er of th this is st stan anda darrd to establish establi sh appr appropria opriate te safety and health practices and deter deter-mine the applicability asfm regulatory limitations prior to use. All specimens are loaded to fracture, at a constant rate of cross-head displacement. Sco Scope pe 1. However, other gage lengths can be used as long as they are practical, and in either case, the value of the gage length must be reported. We are a non-profit group that run this website to share documents. C — Free Download PDF At the same time, the grip facing material must prevent crushing, scoring or other damage to the test specimen that would lead to inaccurate results.

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If this test method is used for free-draining soils the maximum unit weight may not be well defined, and can be less than obtained using Test Methods D In addition, they are representative of the significant digits that generally should be retained. It is beyond the scope of these test methods to consider significant digits used in analytical methods for engineering design. The values stated in SI units are provided for information only, except for units of mass.

The units for mass are given in SI units only, g or kg. This implicitly combines two separate systems of units; that is, the absolute system and the gravitational system. It is scientifically undesirable to combine the use of two separate sets of inch-pound units within a single standard. These test methods have been written using the gravitational system of units when dealing with the inch-pound system. In this system, the pound lbf represents a unit of force weight. 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.

Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. Users should be aware that selling mercury or mercury containing products or both into your state may be prohibited by state law. Significance and Use 5.

In addition, foundation soils are often compacted to improve their engineering properties. Laboratory compaction tests provide the basis for determining the percent compaction and molding water content needed to achieve the required engineering properties, and for controlling construction to assure that the required compaction and water contents are achieved.

If the required degree of compaction is substantially less than the modified maximum dry unit weight using this test method, it may be practicable for testing to be performed using Test Method D and to specify the degree of compaction as a percentage of the standard maximum dry unit weight.

Since more energy is applied for compaction using this test method, the soil particles are more closely packed than when D is used. The general overall result is a higher maximum dry unit weight, lower optimum moisture content, greater shear strength, greater stiffness, lower compressibility, lower air voids, and decreased permeability. However, for highly compacted fine-grained soils, absorption of water may result in swelling, with reduced shear strength and increased compressibility, reducing the benefits of the increased effort used for compaction 2.

Use of D, on the other hand, allows compaction using less effort and generally at a higher optimum moisture content. The compacted soil may be less brittle, more flexible, more permeable, and less subject to effects of swelling and shrinking. In many applications, building or construction codes may direct which test method, D or this one, should be used when specifying the comparison of laboratory test results to the degree of compaction of the in-place soil in the field.

The following subsections describe typical problem soils, the problems encountered when dealing with such soils and possible solutions for these problems. Then use a method specification to control the compaction. Components of a method specification typically contain the type and size of compaction equipment to be used, the lift thickness, acceptable range of molding water content, and number of passes.

Corps of Engineers 5. Both agencies use a different term for these density correction factors. Degradation typically occurs during the compaction of a granular-residual soil or aggregate. When degradation occurs, the maximum dry-unit weight increases 1 so that the resulting laboratory maximum value is not representative of field conditions.

Often, in these cases, the maximum dry unit weight is impossible to achieve in the field. Use of replacement techniques is not correct. To handle these large voids, standard test methods laboratory or field typically have to be modified using engineering judgement.

Users of this standard are cautioned that compliance with Practice D does not in itself assure reliable results. Reliable results depend on many factors; Practice D provides a means of evaluating some of those factors. Keywords compaction characteristics; density; impact compaction using modified effort; laboratory tests; modified proctor test; moisture-density curves; soil compaction;; ICS Number Code Foundation construction.

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ASTM C1557

Tohn If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. A 0 to 8 specksB 9 to 15 specksand C 16 or asgm specks. A viewing box is not mandatory for illumination, but if one is desired, a proposed design for a viewing box is contained in Appendix X1. ASTM D Protect gages that lie idle for extended periods of time from rust with an oil coating or oil soaked wrap. Rounded to nearest 5 m or 0.

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ASTM C1557:14

More C Very short fibers including whiskers call for specialized test techniques 1 3 and are not covered by this test method. This test method may also be useful in the initial screening of candidate fibers for applications in polymer, metal, or ceramic matrix composites, and for quality control purposes. Because of their nature, ceramic fibers do not have a unique tensile strength, but rather a distribution of tensile strengths. In most cases when the tensile strength of the fibers is controlled by one population of flaws, the distribution of fiber tensile strengths can be described using a two-parameter Weibull distribution, although other distributions have also been suggested 2, 3.

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