微信公众号随时随地查标准

QQ交流1群(已满)

QQ群标准在线咨询2

QQ交流2群

购买标准后,可去我的标准下载或阅读

定价: 0元 / 折扣价: 0

在线阅读 收 藏

定价: 0元 / 折扣价: 0

在线阅读 收 藏

定价: 345元 / 折扣价: 294

在线阅读 收 藏

定价: 0元 / 折扣价: 0

在线阅读 收 藏

定价: 345元 / 折扣价: 294

在线阅读 收 藏

定价: 390元 / 折扣价: 332

在线阅读 收 藏

定价: 345元 / 折扣价: 294 加购物车

在线阅读 收 藏

定价: 260元 / 折扣价: 221 加购物车

在线阅读 收 藏

定价: 260元 / 折扣价: 221 加购物车

在线阅读 收 藏

定价: 260元 / 折扣价: 221 加购物车

在线阅读 收 藏

5.1 Rock riprap and armor stone are composed of pieces of natural rock that are placed on construction projects, shorelines, streambeds, bridge abutments, pilings, and other structures to minimize the effects of erosion. The ability of rock to withstand deterioration from weathering affects both the effectiveness of the project and its cost. The specific gravity and absorption of rock provide useful information that can be used in evaluating possible deterioration of rock.5.2 Bulk specific gravity and bulk specific gravity SSD may reflect the quality of rock and is important in that it may provide one indicator to the resistance of a rock to movement by water.5.3 The absorption of water into rock may affect its durability under freezing conditions and salt crystallization conditions. In addition, the absorption test has been used as an index test in determining whether additional tests are needed to evaluate the durability of a rock.5.4 Test specimens equal in size to the proposed design size would provide the best correlations between laboratory tests and actual field performance, however this is usually neither practical nor economically feasible.5.5 The results of these tests are not to be used as the sole basis for determination of rock durability, but should be used in conjunction with the results of other tests.5.6 These test methods have been used to evaluate different types of rocks. There have been rare occasions when test results have provided data that have not agreed with the durability of rock under actual field conditions. For example, some rocks with low absorption values have fragmented in actual usage and some with high absorption values have proven to be durable.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies which meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depends on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method covers the determination of specific gravity and absorption of rock for erosion control, commonly referred to as riprap or armor stone. The specific gravity may be expressed as bulk specific gravity or apparent specific gravity. Bulk specific gravity and absorption are based on a 24 ± 4-h soaking time for the rock specimens tested. This test is appropriate for breakwater stone, armor stone, riprap, and gabion sized rock materials.1.2 The use of reclaimed concrete and other materials is beyond the scope of this test method.1.3 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard.1.4.1 For purposes of comparing measured or calculated value(s) with specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal or significant digits in the specified limits.1.4.2 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.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.

定价: 515元 / 折扣价: 438 加购物车

在线阅读 收 藏

5.1 The water content of a soil is used throughout geotechnical engineering practice both in the laboratory and in the field. The use of Test Method D2216 for water content determination can be time consuming and there are occasions when a more expedient method is desirable. The use of a microwave oven is one such method.5.2 The principal objection to the use of the microwave oven for water-content determination has been the possibility of overheating the soil, thereby yielding a water content higher than would be determined by Test Method D2216. While not eliminating this possibility, the incremental drying procedure described in this test method will minimize its effects. Some microwave ovens have settings at less than full power, which can also be used to reduce overheating.5.3 The behavior of a soil, when subjected to microwave energy, is dependent on its mineralogical compositions, and as a result no one procedure is applicable for all types of soil. Therefore, the procedure recommended in this test method is meant to serve as a guide when using the microwave oven.5.4 This test method is best suited for minus 4.75-mm (No. 4) sieve sized material. Larger size particles can be tested; however, care must be taken because of the increased chance of particle shattering.5.5 The use of this method may not be appropriate when highly accurate results are required, or the test using the data is extremely sensitive to moisture variations.5.6 Due to the localized high temperatures that the specimen is exposed to in microwave heating, the physical characteristics of the soil may be altered. Degregation of individual particles may occur, along with vaporization or chemical transition. It is therefore recommended that samples used in this test method not be used for other tests subsequent to drying.NOTE 1: The quality of the results produced by this test method is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method outlines procedures for determining the water content of soils by incrementally drying soil in a microwave oven.1.2 This test method can be used as a substitute for Test Method D2216 when more rapid results are desired to expedite other phases of testing and slightly less accurate results are acceptable.1.3 When questions of accuracy between this test method and Test Method D2216 arise, Test Method D2216 shall be the referee method.1.4 This test method is applicable for most soil types. For some soils, such as those containing significant amounts of halloysite, mica, montmorillonite, gypsum or other hydrated materials, highly organic soils, or soils in which the pore water contains significant amounts of dissolved solids (such as salt in the case of marine deposits), this test method may not yield reliable water content values due to the potential for heating above 110°C or lack of means to account for the presence of precipitated solids that were previously dissolved.1.5 The values stated in SI units are to be regarded as the standard. Performance of the test method utilizing another system of units shall not be considered non-conformance. The sieve designations are identified using the “standard” system in accordance with Specification E11, such as 2.0-mm and 19-mm, followed by the “alternative” system of No. 10 and 3/4-in., respectively, in parentheses.1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless otherwise superseded by this standard.1.6.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.1.6.2 Significant digits are especially important if the water content will be used to calculate other relationships such as moist mass to dry mass or vice versa, wet unit weight to dry unit weight or vice versa, and total density to dry density or vice versa. For example, if four significant digits are required in any of the above calculations, then the water content has to be recorded to the nearest 0.1 %, for water contents below 100 %. This occurs since 1 plus the water content (not in percent) will have four significant digits regardless of what the value of the water content is (below 100 %); that is, 1 plus 0.1/100 = 1.001, a value with four significant digits. While, if three significant digits are acceptable, then the water content can be recorded to the nearest 1 %.1.7 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. See Section 7.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏

5.1 These test methods are used to determine the in-place density of compacted materials in construction of earth embankments, road fills, and structure backfill. For construction control, these test methods are often used as the bases for acceptance of material compacted to a specified density or to a percentage of a maximum unit weight determined by a standard laboratory test method (such as determined from Test Method D698 or D1557), subject to the limitations discussed in 1.4.5.2 These test methods can be used to determine the in-place density of natural soil deposits, aggregates, soil mixtures, or other similar material.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable testing depends on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 These test methods cover the determination of the in-place density of soil and rock using a pouring device and calibrated sand to determine the volume of a test pit. The word “rock” in these test methods is used to imply that the material being tested will typically contain particles larger than 3 in. [75 mm].1.2 These test methods are best suited for test pits with a volume from 0.03 to 0.17 m3 [1 to 6 ft3]. In general, the materials tested would have a maximum particle size of 75 to 125 mm [3 to 5 in.].1.2.1 For larger sized excavations and soil containing larger particles, Test Method D5030 is preferred.1.2.2 Test Method D1556 or D2167 are usually used to determine the volume of test holes smaller than 0.03 m3 [1 ft3]. While the equipment illustrated in these test methods is used for volumes less than 0.03 m3 [1 ft3], the test methods allow larger versions of the equipment to be used when necessary.1.3 Two test methods are provided as follows:1.3.1 Test Method A—In-Place Density of Total Material (Section 10).1.3.2 Test Method B—In-Place Density of Control Fraction (Section 11).1.4 Selection of Test Methods: 1.4.1 Test Method A is used when the in-place density of total material is to be determined. Test Method A can also be used to determine percent compaction or percent relative density when the maximum particle size present in the in-place material being tested does not exceed the maximum particle size allowed in the laboratory compaction test (refer to Test Methods D698, D1557, D4253, D4254, and D7382). For Test Methods D698 and D1557 only, the dry density determined in the laboratory compaction test may be corrected for larger particle sizes in accordance with, and subject to the limitations of Practice D4718.1.4.2 Test Method B is used when percent compaction or percent relative density is to be determined and the in-place material contains particles larger than the maximum particle size allowed in the laboratory compaction test or when Practice D4718 is not applicable for the laboratory compaction test. Then the material is considered to consist of two fractions, or portions. The material from the in-place dry density test is physically divided into a control fraction and an oversize fraction based on a designated sieve size (see Section 3). The dry density of the control fraction is calculated and compared with the dry density(s) established by the laboratory compaction test(s).1.5 Any materials that can be excavated with hand tools can be tested provided that the void or pore openings in the mass are small enough (or a liner is used) to prevent the calibrated sand used in the test from entering the natural voids. The material being tested should have sufficient cohesion or particle interlocking to maintain stable sides during excavation of the test pit and through completion of this test. It should also be firm enough not to deform or slough due to the minor pressures exerted in digging the hole and pouring the sand.1.6 These test methods are generally limited to material in an unsaturated condition and are not recommended for materials that are soft or friable (crumble easily) or in a water condition such that water seeps into the hand-excavated hole. The accuracy of the test methods may be affected for materials that deform easily or that may undergo volume change in the excavated hole from standing or walking near the hole during the test.1.7 The values stated in either SI units or inch-pound presented in brackets are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.8 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.8.1 The procedures used to specify how data are collected, recorded or calculated in this standard are regarded as the industry standard. In addition they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.1.9 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. For specific hazards statements, see Sections 8 and A1.5.

定价: 646元 / 折扣价: 550 加购物车

在线阅读 收 藏

Limitations:The depth of measurement is limited only by the length of the test hole.Presently, the results of the hydraulic fracturing method can be interpreted in terms of in-situ stresses only if the boreholes are approximately parallel to one of the three principal in-situ stresses. Unless evidence to the contrary exists, vertical boreholes are assumed to be parallel to one of the in-situ principal stresses.When the principal stress parallel to the borehole axis is not the least principal stress, only the two other principal stresses can be determined directly from the test. If the minimum stress acts along the borehole axis, fractures both parallel and perpendicular to the axis of the borehole are sometimes induced by the test, allowing for the determination of all three principal stresses.In the unlikely event that the induced fracture changes orientation away from the borehole, its trace on the borehole wall cannot be used in stress determinations.Assumptions:The rock tested is assumed to be linearly elastic, homogeneous, and isotropic. Any excessive departure from these assumptions could affect the results.Vertical boreholes are assumed to be substantially parallel to one of the in-situ principal stresses, since it has been established from many geological observations and stress measurements by other methods that in most cases one of the principal stresses is vertical to subvertical.Hydraulic fracturing determination of in-situ stresses can be complicated by rock matrix porosity, naturally occurring fractures, the presence of nearby underground openings, and local variations in the stress field.Note 2—The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing/sampling/inspection, etc. Users of this standard are cautioned that compliance with Practice D 3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D 3740 provides a means of evaluating some of those factors.1.1 This test method covers the determination of the in-situ state of stress in rock by hydraulic fracturing.Note 1—Hydraulic fracturing for stress determination is also referred to as hydrofracturing, and sometimes as minifracing. Hydraulic fracturing and hydrofracturing may also refer to fracturing of the rock by fluid pressure for the purpose of altering rock properties, such as permeability and porosity.1.2 Hydraulic fracturing is the widely accepted field method available for in situ stress measurements at depths greater than 50 m. It can be used in drill holes of any diameter.1.3 Hydraulic fracturing can also be used in short holes for which other stress measuring methods, such as overcoring, are also available. The advantage of hydraulic fracturing is that it yields stresses averaged over a few square metres (the size of the induced hydraulic fracture) rather than over grain size areas, as in the case of overcoring techniques.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D 6026.1.4.1 The method used to specifiy how data are collected, calculated, or recorded in this standard is not directly related to the accuracy to which the data can be applied in design or other uses, or both. How one applies the results obtained using this standard is beyond its scope.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety problems, 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.

定价: 0元 / 折扣价: 0

在线阅读 收 藏

5.1 The parameters obtained from Methods A and B are in terms of undrained total stress. However, there are some cases where either the rock type or the loading condition of the problem under consideration will require the effective stress or drained parameters be determined. 5.2 Method C, uniaxial compressive strength of rock is used in many design formulas and is sometimes used as an index property to select the appropriate excavation technique. Deformation and strength of rock are known to be functions of confining pressure. Method A, triaxial compression test, is commonly used to simulate the stress conditions under which most underground rock masses exist. The elastic constants (Methods B and D) are used to calculate the stress and deformation in rock structures. 5.3 The deformation and strength properties of rock cores measured in the laboratory usually do not accurately reflect large-scale in situ properties because the latter are strongly influenced by joints, faults, inhomogeneity, weakness planes, and other factors. Therefore, laboratory values for intact specimens shall be employed with proper judgment in engineering applications. Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means for evaluating some of those factors. 1.1 These four test methods cover the determination of the strength of intact rock core specimens in uniaxial and triaxial compression. Methods A and B determine the triaxial compressive strength at different pressures and Methods C and D determine the unconfined, uniaxial strength. 1.2 Methods A and B can be used to determine the angle of internal friction, angle of shearing resistance, and cohesion intercept. 1.3 Methods B and D specify the apparatus, instrumentation, and procedures for determining the stress-axial strain and the stress-lateral strain curves, as well as Young's modulus, E, and Poisson's ratio, υ. These methods do not make provisions for pore pressure measurements and specimens are undrained (platens are not vented). Thus, the strength values determined are in terms of total stress and are not corrected for pore pressures. These test methods do not include the procedures necessary to obtain a stress-strain curve beyond the ultimate strength. 1.4 Option A allows for testing at different temperatures and can be applied to any of the test methods, if requested. 1.5 This standard replaces and combines the following Standard Test Methods: D2664 Triaxial Compressive Strength of Undrained Rock Core Specimens Without Pore Pressure Measurements; D5407 Elastic Moduli of Undrained Rock Core Specimens in Triaxial Compression Without Pore Pressure Measurements; D2938 Unconfined Compressive Strength of Intact Rock Core Specimens; and D3148 Elastic Moduli of Intact Rock Core Specimens in Uniaxial Compression. The original four standards are now referred to as Methods in this standard. 1.5.1 Method A—Triaxial Compressive Strength of Undrained Rock Core Specimens Without Pore Pressure Measurements. 1.5.1.1 Method A requires strength determination only. Strain measurements and a stress-strain curve are not required. 1.5.2 Method B—Elastic Moduli of Undrained Rock Core Specimens in Triaxial Compression Without Pore Pressure Measurements. 1.5.3 Method C—Uniaxial Compressive Strength of Intact Rock Core Specimens. 1.5.3.1 Method C requires strength determination only. Strain measurements and a stress-strain curve are not required. 1.5.4 Method D—Elastic Moduli of Intact Rock Core Specimens in Uniaxial Compression. 1.5.5 Option A: Temperature Variation—Applies to any of the methods and allows for testing at temperatures above or below room temperature. 1.6 For an isotropic material in Test Methods B and D, the relation between the shear and bulk moduli and Young's modulus and Poisson's ratio are: where: G   =   shear modulus, K   =   bulk modulus, E   =   Young's modulus, and υ   =   Poisson's ratio. 1.6.1 The engineering applicability of these equations decreases with increasing anisotropy of the rock. It is desirable to conduct tests in the plane of foliation, cleavage or bedding and at right angles to it to determine the degree of anisotropy. It is noted that equations developed for isotropic materials may give only approximate calculated results if the difference in elastic moduli in two orthogonal directions is greater than 10 % for a given stress level. Note 1: Elastic moduli measured by sonic methods (Test Method D2845) may often be employed as a preliminary measure of anisotropy. 1.7 Test Methods B and D for determining the elastic constants do not apply to rocks that undergo significant inelastic strains during the test, such as potash and salt. The elastic moduli for such rocks should be determined from unload-reload cycles that are not covered by these test methods. 1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this test method. 1.9 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. 1.9.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design. 1.10 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价: 590元 / 折扣价: 502 加购物车

在线阅读 收 藏
90 条记录,每页 15 条,当前第 1 / 6 页 第一页 | 上一页 | 下一页 | 最末页  |     转到第   页