5.1 Assumptions: 5.1.1 Well discharges at a constant rate, Q.5.1.2 Well is of infinitesimal diameter and fully penetrates the aquifer, that is, the well is open to the full thickness of the aquifer.5.1.3 The nonleaky aquifer is homogeneous, isotropic, and areally extensive. A nonleaky aquifer receives insignificant contribution of water from confining beds.5.1.4 Discharge from the well is derived exclusively from storage in the aquifer.5.1.5 The geometry of the assumed aquifer and well conditions are shown in Fig. 1.5.2.3 Application of Theis Nonequilibrium Method to Unconfined Aquifers: 5.2.3.1 Although the assumptions are applicable to confined conditions, the Theis solution may be applied to unconfined aquifers if drawdown is small compared with the saturated thickness of the aquifer or if the drawdown is corrected for reduction in thickness of the aquifer and the effects of delayed gravity yield are small.5.2.3.2 Reduction in Aquifer Thickness—In an unconfined aquifer, dewatering occurs when the water levels decline in the vicinity of a pumping well. Corrections in drawdown need to be made when the drawdown is a significant fraction of the aquifer thickness as shown by Jacob (8). The drawdown, s, needs to be replaced by s′, the drawdown that would occur in an equivalent confined aquifer, where:5.2.3.3 Gravity Yield Effects—In unconfined aquifers, delayed gravity yield effects may invalidate measurements of drawdown during the early part of the test for application to the Theis method. Effects of delayed gravity yield are negligible in partially penetrating observation wells at a distance, r, from the control well, where:after the time, t, as given in the following equation from Neuman (9):where:Sy   =   the specific yield.For fully penetrating observation wells, the effects of delayed yield are negligible at the distance, r, in Eq 11 after one tenth of the time given in the Eq 12.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/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.NOTE 3: The injection of water into an aquifer may be regulated or require regulatory approvals. Withdrawal of contaminated waters may require that the removed water be properly treated prior to discharge.1.1 This practice covers an analytical procedure for determining transmissivity and storage coefficient of a nonleaky confined aquifer under conditions of radial flow to a fully penetrating well of constant flux. This practice is a shortcut procedure used to apply the Theis nonequilibrium method. The Theis method is described in Practice D4106.1.2 This practice, along with others, is used in conjunction with the field procedure given in Test Method D4050.1.3 Limitations—The limitations of this practice are primarily related to the correspondence between the field situation and the simplifying assumptions of this practice (see 5.1). Furthermore, application is valid only for values of u less than 0.01 (u is defined in Eq 2, in 8.6).1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 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.1.5 Units—The values stated in either SI Units or inch-pound units are to be regarded separately as standard. The values 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. Reporting of results in units other than SI shall not be regarded as nonconformance with this practice.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 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.

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5.1 This practice is one of several available for determining vertical anisotropy ratio. Among other available methods are Weeks ((5); see Practice D5473/D5473M), that relies on distance-drawdown data, and Way and McKee (6), that utilizes time-drawdown data. An important restriction of the Weeks distance-drawdown method is that the observation wells need to have identical construction (screened intervals) and two or more of the observation wells need to be located at a distance from the pumped well beyond the effects of partial penetration. The procedure described in this practice general distance-drawdown method, in that it works in theory for most observation well configurations incorporating three or more wells, provided some of the wells are within the zone where flow is affected by partial penetration.5.2 Assumptions: 5.2.1 Control well discharges at a constant rate, Q.5.2.2 Control well is of infinitesimal diameter and partially penetrates the aquifer.5.2.3 Data are obtained from a number of partially penetrating observation wells, some screened at elevations similar to that in the pumped well and some screened at different elevations.5.2.4 The aquifer is confined, homogeneous and areally extensive. The aquifer may be anisotropic, and, if so, the directions of maximum and minimum hydraulic conductivity are horizontal and vertical, respectively.5.2.5 Discharge from the well is derived exclusively from storage in the aquifer.5.3 Calculation Requirements—Application of this method is computationally intensive. The function, fs, shown in (Eq 4) should be evaluated numerous times using arbitrary input parameters. It is not practical to use existing, somewhat limited, tables of values for fs and, because this equation is rather formidable, it may not be easily tractable by hand. Because of this, it is assumed the practitioner using this will have available a computerized procedure for evaluating the function fs. This can be accomplished using commercially available mathematical software including some spreadsheet applications, or by writing programs. (7)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/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.NOTE 3: Most fractured (unconfined) aquifers, even noncarbonates, will have some form of convergent flow to master fissures or channels (Worthington et al., 2016). A relationship is known to occur in carbonates where potentiometric troughs correspond with sub-surface conduits or channels (Quinlan and Ewers, 1989).NOTE 4: Commercially available software is available for the calculating, graphing, plotting, and analyses of this practice. The user should verify the correctness of the formulas, graphs, plots and analyses of the software.1.1 This practice covers an analytical procedure for determining the transmissivity, storage coefficient, and ratio of vertical to horizontal hydraulic conductivity of a confined aquifer using observation well drawdown measurements from a constant-rate pumping test. This practice uses data from a minimum of four partially penetrating, recommended to be positioned observation wells around a partially penetrating control well.1.2 The analytical procedure is used in conjunction with the field procedure in Test Method D4050.1.3 Limitations—The limitations of the technique for determination of the horizontal and vertical hydraulic conductivity of aquifers are primarily related to the correspondence between the field situation and the simplifying assumption of this practice.1.4 Units—The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are mathematical conversions, which are provided for information purposes only and are not considered standard. The reporting of results in units other than inch-pound shall not be regarded as nonconformance with this standard.1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard.1.6 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 objective; and it is common practice to increase or reduce the 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 method or engineering design.1.7 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.8 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.1.9 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.

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This practice covers procedures that can be followed to safeguard against the possible embrittlement of steel hot-dip galvanized after fabrication, and outlines test procedures for detecting embrittlement. Conditions of fabrication may induce a susceptibility to embrittlement in certain steels that can be accelerated by galvanizing. Open-hearth, basic-oxygen, and electric-furnace steels shall be used for galvanizing. Other materials that can be galvanized include continuous cast slabs, steel or iron castings, and wrought iron. The material shall undergo cold working and thermal treatment. Embrittlement of steel shapes, steel castings, threaded articles, and hardware items shall be tested using a bend test , a universal testing machine, or by means of a press with the load applied slowly, until fracture of the galvanized test specimen occurs.1.1 This practice covers procedures that can be followed to safeguard against the possible embrittlement of steel hot-dip galvanized after fabrication, and outlines test procedures for detecting embrittlement. Conditions of fabrication may induce a susceptibility to embrittlement in certain steels that can be accelerated by galvanizing. Embrittlement is not a common occurrence, however, and this discussion does not imply that galvanizing increases embrittlement where good fabricating and galvanizing procedures are employed. Where history has shown that for specific steels, processes and galvanizing procedures have been satisfactory, this history will serve as an indication that no embrittlement problem is to be expected for those steels, processes, and galvanizing procedures.1.2 This practice is applicable in either inch-pounds or SI units. Inch-pounds and SI units are not necessarily exact equivalents. Within the text of this practice and where appropriate, SI units are shown in brackets.1.3 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.1.4 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.

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5.1 Assumptions of Solution: 5.1.1 Drawdown (or mounding) of the water table around the well is negligible.5.1.2 Flow above the water table can be ignored.5.1.3 Head losses as the water enters or leaves the well are negligible.5.1.4 The aquifer is homogeneous and isotropic.NOTE 6: Slug and pumping tests implicitly assume a porous medium. Fractured rock and carbonate settings may not provide meaningful data and information.5.2 Implications of Assumptions: 5.2.1 The mathematical equations applied ignore inertial effects and assume that the water level returns to the static level in an approximate exponential manner.5.2.2 The geometric configuration of the well and aquifer are shown in Fig. 1, that is after Fig. 1 of Bouwer and Rice (1).NOTE 7: Short term refers to the duration of the slug test.NOTE 8: The function of wells in any unconfined setting in a fractured terrain might make the determination of k problematic because the wells might only intersect tributary or subsidiary channels or conduits. The problems determining the k of a channel or conduit notwithstanding, the partial penetration of tributary channels may make a determination of a meaningful number difficult. If plots of k in carbonates and other fractured settings are made and compared, they may show no indication that there are conduits or channels present, except when with the lowest probability one maybe intersected by a borehole and can be verified, such problems are described by Smart (1999) (6). Additional guidance can be found in Guide D5717.NOTE 9: The comparison of data from various methods on variable head permeability tests has been documented. Variation in instrumentation, assumptions and calculational methods will lead to differing results (7). Users should be familiar with the assumptions, instrumentation and calculational aspects of the test when evaluating the results (8).NOTE 10: 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/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers the determination of hydraulic conductivity from the measurement of inertial force free (overdamped) response of a well-aquifer system to a sudden change in water level in a well. Inertial force free response of the water level in a well to a sudden change in water level is characterized by recovery to initial water level in an approximate exponential manner with negligible inertial effects.1.2 The analytical procedure in this practice is used in conjunction with the field procedure in Test Method D4044/D4044M for collection of test data.1.3 Limitations—Slug tests are considered to provide an estimate of hydraulic conductivity. The determination of storage coefficient is not practicable with this practice. Because the volume of aquifer material tested is small, the values obtained are representative of materials very near the open portion of the control well.NOTE 1: Slug tests are usually considered to provide estimates of the lower limit of the actual hydraulic conductivity of an aquifer because the test results are so heavily influenced by well efficiency and borehole skin effects near the open portion of the well. The portion of the aquifer that is tested by the slug test is limited to an area near the open portion of the well where the aquifer materials may have been altered during well installation, and therefore may significantly impact the test results. In some cases, the data may be misinterpreted and result in a higher estimate of hydraulic conductivity. This is due to the reliance on early time data that is reflective of the hydraulic conductivity of the filter pack surrounding the well. This effect was discussed by Bouwer (1).2 In addition, because of the reliance on early time data, in aquifers with medium to high hydraulic conductivity, the early time portion of the curve that is useful for this data analyses is too short (for example, <10 s) for accurate measurement; therefore, the test results begin to greatly underestimate the true hydraulic conductivity.1.4 Units—The values stated in SI units are to be regarded as the 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 standard.1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.5.1 The procedures used to specify how data are collected/recorded and calculated in the 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 these test methods to consider significant digits used in analysis methods for engineering data.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through he ASTM consensus process.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 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 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 646元 加购物车

定价： 590元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

5.1 Driveability problems in PFI automobiles were first reported in 1984. Deposits are prone to form on the metering surfaces of pintle-type electronic fuel injectors. These deposits reduce fuel flow through the metering orifices. Reductions in metered fuel flow result in an upset in the air-fuel ratio, which can affect emissions and driveability. When heavy enough, these deposits can lead to driveability symptoms, such as hesitation, hard starting, or loss of power, or a combination thereof, that are easily noticed by the average driver and that lead to customer complaints. The mechanism of the formation of deposits is not completely understood. It is believed to be influenced by many factors, including driving cycle, engine and injector design, and composition of the fuel. The procedure in this test method has been found to build deposits in PFIs on a consistent basis. This procedure can be used to evaluate differences in base fuels and fuel additives. A study of PFI fouling was conducted in both the bench test and the vehicle test procedures to obtain a correlation. The vehicle tests were conducted as described in Test Method D5598. The tests were conducted on several base gasolines, with and without additives blended into these base fuels. The PFI bench test proved to be reliable, repeatable, and a good predictor of PFI fouling in test vehicles.5.1.1 State and Federal Legislative and Regulatory Action—Legislative and regulatory activity, primarily by the state of California (see 2.3) and the federal government (see 2.4), necessitate the acceptance of a standard test method to evaluate the PFI deposit-forming tendency of an automotive spark-ignition engine fuel.5.1.2 Relevance of Results—The operating conditions and design of the laboratory apparatus used in this test method may not be representative of a current vehicle fuel system. These factors must be considered when interpreting results.5.2 Test Validity: 5.2.1 Procedural Compliance—The test results are not considered valid unless the test is completed in compliance with all requirements of this test method. Deviations from the parameter limits presented in Section 10 will result in an invalid test. Engineering judgment shall be applied during conduct of the test method when assessing any anomalies to ensure validity of the test results.1.1 This test method covers a bench test procedure to evaluate the tendency of automotive spark-ignition engine fuel to foul electronic port fuel injectors (PFI). The test method utilizes a bench apparatus equipped with Bosch injectors specified for use in a 1985-1987 Chrysler 2.2 L turbocharged engine. This test method is based on a test procedure developed by the Coordinating Research Council (CRC) for prediction of the tendency of spark-ignition engine fuel to form deposits in the small metering clearances of injectors in a port fuel injection engine (see CRC Report No. 592).21.2 The test method is applicable to spark-ignition engine fuels, which may contain antioxidants, corrosion inhibitors, metal deactivators, dyes, deposit control additives, demulsifiers, or oxygenates, or a combination thereof.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.4 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. Specific precautionary statements are given throughout this test method.NOTE 1: If there is any doubt as to the latest edition of Test Method D6421, contact ASTM International Headquarters. Other properties of significance to spark-ignition engine fuel are described in Specification D4814.1.5 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： 646元 加购物车

定价： 646元 加购物车

定价： 646元 加购物车

定价： 646元 加购物车

5.1 This test method is considered satisfactory for acceptance testing of commercial shipments since current estimates of between-laboratory precision are acceptable, and the test method is used extensively in the trade for acceptance testing.5.1.1 In case of a dispute arising from differences in reported test results when using this test method for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible and that are from a lot of fabric of the type in question. Test specimens then should be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using the appropriate statistical analysis and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found, either its cause must be found and corrected, or the purchaser and the supplier must agree to interpret future test results with consideration to the known bias.5.2 The force registered in a tear test is irregular, and as a consequence, empirical methods have had to be developed to obtain usable values related to tear strength. In spite of the empirical nature of the reported values, the values are considered to reflect comparative performance of similar fabrics tested and measured in the same way. No known procedure is available that can be used with all fabrics to determine the minimum tearing strength.5.3 Depending on the nature of the specimen, the data recording devices will show the tearing force in the form of a peak or peaks. The highest peaks appear to reflect the strength of the yarn components, fiber bonds, or fiber interlocks, individually or in combination, needed to stop a tear in a fabric of the same construction. The valleys recorded between the peaks have no specific significance. The minimum tearing force, however, is indicated to be above the lowest valleys.5.4 Most textile fabrics can be tested by this test method. Some modification of clamping techniques may be necessary for a given fabric due to its structure. Strong fabrics or fabrics made from glass fibers usually require special adaptation to prevent them from slipping in the clamps or being damaged as a result of being gripped in the clamps.5.5 The CRE-type tensile testing machine has become the preferred test apparatus for determining tongue tearing strength. It is recognized that some constant-rate-of-traverse-type (CRT) tensile testing machines continue to be used. Consequently, these test instruments may be used when agreed upon between the purchaser and the supplier. The conditions for use of the CRT-type tester are included in Appendix X1.1.1 This test method covers the measurement of the tearing strength of textile fabrics by the tongue (single rip) procedure using a recording constant-rate-of-extension-type (CRE) tensile testing machine.1.1.1 The CRE-type tensile testing machine has become the preferred test apparatus for determining tongue tearing strength. It is recognized that some constant-rate-of-traverse-type (CRT) tensile testing machines continue to be used. As a consequence, these test instruments may be used when agreed upon between the purchaser and the supplier. The conditions for use of the CRT-type tensile tester are included in Appendix X1.1.2 This test method applies to most fabrics including woven fabrics, air bag fabrics, blankets, napped fabrics, knit fabrics, layered fabrics, pile fabrics and non-wovens. The fabrics may be untreated, heavily sized, coated, resin-treated, or otherwise treated. Instructions are provided for testing specimens with or without wetting.1.3 Tear strength, as measured in this test method, requires that the tear be initiated before testing. The reported value obtained is not directly related to the force required to initiate or start a tear.1.4 Two calculations for tongue tearing strength are provided: the single-peak force and the average of five highest peak forces.1.5 The values stated in either SI units or inch-pound units are to be regarded as the standard. The inch-pound units may be approximate.1.6 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.1.7 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.

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6.1 The assumptions of the physical system are given as follows:6.1.1 The aquifer is of uniform thickness and confined by impermeable beds above and below.6.1.2 The aquifer is of constant homogeneous porosity and matrix compressibility and of homogeneous and isotropic hydraulic conductivity.6.1.3 The origin of the cylindrical coordinate system is taken to be on the well-bore axis at the top of the aquifer.6.1.4 The aquifer is fully screened.6.2 The assumptions made in defining the momentum balance are as follows:6.2.1 The average water velocity in the well is approximately constant over the well-bore section.6.2.2 Flow is laminar and frictional head losses from flow across the well screen are negligible.6.2.3 Flow through the well screen is uniformly distributed over the entire aquifer thickness.6.2.4 Change in momentum from the water velocity changing from radial flow through the screen to vertical flow in the well are negligible.6.2.5 The system response is an exponentially decaying sinusoidal function.NOTE 3: 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/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers determination of transmissivity from the measurement of the damped oscillation about the equilibrium water level of a well-aquifer system to a sudden change of water level in a well. Underdamped response of water level in a well to a sudden change in water level is characterized by oscillatory fluctuation about the static water level with a decrease in the magnitude of fluctuation and recovery to initial water level. Underdamped response may occur in wells tapping highly transmissive confined aquifers and in deep wells having long water columns.1.2 This analytical procedure is used in conjunction with the field procedure Test Method D4044/D4044M for collection of test data.1.3 Limitations—Slug tests are considered to provide an estimate of transmissivity of a confined aquifer. This test method requires that the storage coefficient be known. Assumptions of this practice prescribe a fully penetrating well (a well open through the full thickness of the aquifer), but the slug test method is commonly conducted using a partially penetrating well. Such a practice may be acceptable for application under conditions in which the aquifer is stratified and horizontal hydraulic conductivity is much greater than vertical hydraulic conductivity. In such a case the test would be considered to be representative of the average hydraulic conductivity of the portion of the aquifer adjacent to the open interval of the well. The method assumes laminar flow and is applicable for a slug test in which the initial water-level displacement is less than 0.1 or 0.2 of the length of the static water column.1.4 This practice for analysis presented here is derived by van der Kamp (1)2 based on an approximation of the underdamped response to that of an exponentially damped sinusoid. A more rigorous analysis of the response of wells to a sudden change in water level by Kipp (2) indicates that the method presented by van der Kamp (1) matches the solution of Kipp (2) when the damping parameter values are less than about 0.2 and time greater than that of the first peak of the oscillation (2).1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values 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. Reporting of test results in units other than SI shall not be regarded as nonconformance with this practice.1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.7 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.8 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.1.9 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 加购物车