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 Assumptions:  5.1.1 Well discharges at a constant rate, Q. 5.1.2 Well is of infinitesimal diameter and fully penetrates the aquifer. 5.1.3 The nonleaky aquifer is homogeneous, isotropic, and aerially 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 Method to Unconfined Aquifers:  5.2.3.1 Although the assumptions are applicable to artesian or 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 (5). 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 and beyond a distance, r, from the control well, where: After the time, t, as given in Eq 9 from Neuman (6). where: Sy   =   the specific yield. For fully penetrating observation wells, the effects of delayed yield are negligible at the distance, r, in Eq 8 after one tenth of the time given in the Eq 9. 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/sampling/inspection/etc. 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 of evaluating some of those factors. 1.1 This practice covers an analytical procedure for determining the transmissivity and storage coefficient of a nonleaky confined aquifer. It is used to analyze data on water-level response collected during radial flow to or from a well of constant discharge or injection. 1.2 This analytical procedure, along with others, is used in conjunction with the field procedure given in Test Method D4050. 1.3 Limitations—The limitations of this practice for determination of hydraulic properties of aquifers are primarily related to the correspondence between the field situation and the simplifying assumptions of this practice (see 5.1). 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 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. 1.6 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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5.1 The coefficient of linear thermal expansion, α, between temperatures T1 and T2 for a specimen whose length is L0 at the reference temperature, is given by the following equation:Where L1 and L2 are the specimen lengths at temperatures T1 and T2, respectively. α is, therefore, obtained by dividing the linear expansion per unit length by the change in temperature.5.2 The nature of most plastics and the construction applications for which plastic lumber and plastic lumber shapes are used, make –30 to 140°F (–34.4 to 60°C) a practical temperature range for linear thermal expansion measurements. Where testing outside of this temperature range or when linear thermal expansion characteristics of a particular plastic are not known through this temperature range, particular attention shall be paid to the factors mentioned in 1.2 and it is possible that special preliminary investigations by thermo-mechanical analysis, such as what is prescribed in Practice D4065 for the location of transition temperatures, will be required, in order to avoid excessive error. If such a transition point is located, a separate coefficient of expansion for a temperature range below and above the transition point shall be determined. For specification and comparison purposes (provided it is known that no transition exists in this range), the range from –30 to 140°F (–34.4 to 60°C) shall be used. (For reference, glass transition and melting point temperatures of typical resins used in plastic lumber products are given in Appendix X2 of this test method.)1.1 This test method covers the determination of the coefficient of linear thermal expansion for plastic lumber and plastic lumber shapes to two significant figures. The determination is made by taking measurements with a caliper at three discrete temperatures. At the test temperatures and under the stresses imposed, the plastic lumber shall have a negligible creep or elastic strain rate, or both, insofar as these properties would significantly affect the accuracy of the measurements.1.1.1 This test method details the determination of the linear coefficient of thermal expansion of plastic lumber and plastic lumber shapes in their “as manufactured” form. As such, this is a test method for evaluating the properties of plastic lumber or shapes as a product and not a material property test method.1.2 The thermal expansion of plastic lumber and shapes is composed of a reversible component on which it is possible to superimpose changes in length due to changes in moisture content, curing, loss of plasticizer or solvents, release of stresses, phase changes, voids, inclusions, and other factors. This test method is intended to determine the coefficient of linear thermal expansion under the exclusion of non-linear factors as far as possible. In general, it will not be possible to exclude the effect of these factors completely. For this reason, the test method can be expected to give a reasonable approximation but not necessarily precise determination of the linear coefficient of thermal expansion.1.3 Plastic lumber and plastic lumber shapes are currently made predominately with recycled plastics where the product is non-homogeneous in the cross-section. However, it is possible that this test method will also be applicable to similar manufactured plastic products made from virgin resins or other plastic composite materials.1.4 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are for information only.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this standard.1.6 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 Information concerning the thermal expansion characteristics of rocks is important in the design of underground excavation where the temperature of the surrounding rock may be altered. Depending on the restraint conditions, thermal strain may cause thermal stress that may affect the stability of underground excavations. Examples of applications where an understanding of rock thermal strain is important include: nuclear waste repositories, underground power stations, compressed air energy storage facilities, energy foundations, and geothermal energy facilities.5.2 The coefficient of linear thermal expansion, α, of rock is known to vary as the temperature changes. Rock thermal strain is normally not a linear function of temperature. This test method provides a procedure for continuously monitoring thermal strain as a function of temperature. Therefore, information on how the coefficient of linear thermal expansion changes with temperature is obtained.5.3 Other methods of measuring the coefficient of linear thermal expansion of rock by averaging the thermal strain of a large specimen over a temperature range of many degrees may result in failure to determine the variation in α of that rock for one or more of the following reasons:5.3.1 α is not always linear with temperature,5.3.2 Some rocks are anisotropic having directional characteristics which can vary by more than a factor of two. If anisotropy is expected, specimen with different orientations should be prepared and tested.5.3.3 α may have a negative value in one direction and, at the same time, a positive value in the others.5.4 Both wire and foil type strain gauges have been successfully employed to measure the thermal expansion coefficients of rock. These coefficients are frequently very small, being on the order of millionths of a millimetre per millimetre for each degree Celsius. The thermal strain of rocks is about one-tenth that of plastics and one-half or one-quarter that of many metals. Therefore, measurement methods for rocks require greater precision than methods that are routinely used on plastics and metals.NOTE 4: The quality of the results 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 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 covers the laboratory determination of the linear (one-dimensional) coefficient of thermal expansion of rock using bonded electric resistance strain gauges. This test method is intended for evaluation of intact rock cores. Discontinuities in the rock mass, such as joints, inclusions, voids, veins, bedding, and the like can influence the thermal expansion of the rock, and judgment should be used when selecting the specimen to be analyzed in this test method.1.2 This test method is applicable for unconfined stress states over the temperature range from 20 to 260°C.NOTE 1: Unconfined tests performed at elevated temperatures may alter the mineralogy or grain structure of the test specimen. This alteration may change the physical and thermal properties of the test specimen.NOTE 2: The strain gauges are mounted with epoxy. Most commercially available high temperature epoxies require elevated temperature curing. The elevated temperature required for this curing may alter the physical and thermal properties of the test specimen. Epoxy should be selected based upon the maximum expected test temperature. Room temperature curing epoxy should be used whenever practical.1.3 The test specimens may be either saturated, dry or unsaturated. If saturated or unsaturated specimens are used, then the test temperature shall be at least 10°C less than the boiling point of the saturating fluid in order to reduce the effects of evaporation of the fluid.NOTE 3: When testing a saturated specimen, the gravimetric water content of the specimen may change unless special precautions are taken to encapsulate the test specimen. Refer to 7.4.1.4 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.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 procedure 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.1.6 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 and health practices and determine the applicability of regulatory requirements prior to use.

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1.1 This test method covers determination of the coefficient of linear thermal expansion of electrical insulating materials by use of a thermomechanical analyzer.1.2 This test method is applicable to materials that are solid over the entire range of temperature used, and that retain sufficient hardness and rigidity over the temperature range so that irreversible indentation of the specimen by the sensing probe does not occur.1.3 Transition temperatures also may be obtained by this test method.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 and health practices and determine the applicability of regulatory limitations prior to use.1.5 The values stated in SI units are the standard.Note 1--There is no similar or equivalent ISO/IEC standard.

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4.1 Knowledge of the coefficient of thermal expansion of a liquid is essential to compute the required size of a container to accommodate a volume of liquid over the full temperature range to which it will be subjected. It is also used to compute the volume of void space that would exist in an inelastic device filled with the liquid after the liquid has cooled to a lower temperature.1.1 This practice covers the determination of the coef-ficient of thermal expansion of electrical insulating liquids of petroleum origin, and askarels, containing PCBs (polychlorinated biphenyls), when used as an insulating or cooling medium, or both, in cables, transformers, oil circuit breakers, capacitors, or similar apparatus.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 The absorption coefficient of polyolefin polymer pigmented with carbon black is useful to judge the degree and uniformity of dispersion of the pigment, and the adequacy of the quantitative level of pigment addition. These factors are used to predict the performance of the polymer material in response to prolonged exposure to ultraviolet light as evidenced by minimal changes in specific properties.NOTE 1: This test method was developed to evaluate ethylene polymer materials pigmented with small particle size carbon blacks suitable for UV protection. It is not known how accurate and reproducible the test would be with larger (35 nm or greater) particle size blacks. However, for larger particle sizes of carbon black, such as furnace black at 275 nm, when there is at least 5 or higher percent of carbon black, the material pigmented as such has suitable UV protection.1.1 This test method measures the amount of light transmitted through a film of carbon black pigmented ethylene polymer.1.2 After calculation of the amount of light and film thickness, an absorption coefficient is calculated.1.3 Whenever two sets of values are presented, in different units, the values in the first set are the standard, while those in parentheses are for information only.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.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.

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1.1 This test method covers the determination of the coefficient of static friction of corrugated and solid fiberboard or of the materials used to make such board. 1.2 This test method contains the following two methods: 1.2.1 Horizontal Plane Method -The horizontal instrument requires some means of movement of the specimen in relation to the surface upon which it rests. The coefficient of friction is measured directly from the resistance to that force and the applied weight (see 7.1). 1.2.2 Inclined Plane Method -The incline plane is raised until sliding begins. The coefficient of friction is equal to the tangent of the angle at which sliding begins (see 7.2). 1.3 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only. 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 whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 In order to choose the proper material for producing semiconductor devices, knowledge of material properties such as resistivity, Hall coefficient, and Hall mobility is useful. Under certain conditions, as outlined in the Appendix, other useful quantities for materials specification, including the charge carrier density and the drift mobility, can be inferred.1.1 These test methods cover two procedures for measuring the resistivity and Hall coefficient of single-crystal semiconductor specimens. These test methods differ most substantially in their test specimen requirements.1.1.1 Test Method A, van der Pauw (1) 2—This test method requires a singly connected test specimen (without any isolated holes), homogeneous in thickness, but of arbitrary shape. The contacts must be sufficiently small and located at the periphery of the specimen. The measurement is most easily interpreted for an isotropic semiconductor whose conduction is dominated by a single type of carrier.1.1.2 Test Method B, Parallelepiped or Bridge-Type—This test method requires a specimen homogeneous in thickness and of specified shape. Contact requirements are specified for both the parallelepiped and bridge geometries. These test specimen geometries are desirable for anisotropic semiconductors for which the measured parameters depend on the direction of current flow. The test method is also most easily interpreted when conduction is dominated by a single type of carrier.1.2 These test methods do not provide procedures for shaping, cleaning, or contacting specimens; however, a procedure for verifying contact quality is given.NOTE 1: Practice F418 covers the preparation of gallium arsenide phosphide specimens.1.3 The method in Practice F418 does not provide an interpretation of the results in terms of basic semiconductor properties (for example, majority and minority carrier mobilities and densities). Some general guidance, applicable to certain semiconductors and temperature ranges, is provided in the Appendix. For the most part, however, the interpretation is left to the user.1.4 Interlaboratory tests of  these test methods (Section 19) have been conducted only over a limited range of resistivities and for the semiconductors, germanium, silicon, and gallium arsenide. However, the method is applicable to other semiconductors provided suitable specimen preparation and contacting procedures are known. The resistivity range over which the method is applicable is limited by the test specimen geometry and instrumentation sensitivity.1.5 The values stated in acceptable metric units are to be regarded as the standard. The values given in parentheses are for information only. (See also 3.1.4.)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 and health 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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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 test method covers the measurement of the longitudinal friction coefficient with a measurement device that imposes braking-slip between a tire and a surface for the full range of braking-slip speed values. The test apparatus consists of an automotive vehicle with one or two independently functioning test wheel systems incorporated into it. Each test wheel system contains a continuously variable brake system and a pavement wetting system. The overall system is controlled by a programmable control unit. The test apparatus is brought to the desired test speed. A controlled amount of water is optionally delivered ahead of the test tire and the braking system is actuated to control the slip ratio of the test wheel. The resulting resistive force from friction acting between the test tire and pavement surface is sampled, filtered, calculated, and recorded by suitable data acquisition routines. For tire comparison testing two identical test wheels, both are subjected to the same test run control logic for equal spin velocities and loads in parallel wheel paths on the same test track. The braking slip friction coefficient of the paved road surface is calculated and reported as slip friction numbers. The slip friction numbers are typically presented in a graphical form. Cartesian plots of slip friction numbers versus slip speed or slip ratio are presented with identification of: peak friction value, critical slip ratio, slip-to-skid friction number, slope of the tangent at zero slip speed of the curve, and slope of the logarithm curve at high slip ratio.1.1 This test method covers the measurement of the longitudinal friction coefficient with a measurement device that imposes braking slip between a tire and a surface for the full range of braking slip speed values.1.2 This test method utilizes a series of incremental single measurements of friction force on a braked test wheel as it is pulled over a wetted or contaminated pavement surface. The rotational velocity of the braked wheel is feedback controlled in order to give a predetermined variable slip ratio gradient in accordance with set program parameters. The test wheel is kept under a constant static normal load and at a constant longitudinal speed of travel. Its major plane is perpendicular to the road plane and parallel to its direction of motion.1.3 The values measured represent the friction properties obtained with the equipment and procedures stated in this test method and do not necessarily agree or correlate directly with those obtained by other pavement friction measuring methods.1.4 The values are intended for use in:1.4.1 Evaluating the braking friction forces on a pavement relative to that of other pavements.1.4.2 Evaluating changes in the braking friction forces of a particular pavement with the passage of time.1.4.3 Evaluating the changes in the braking friction force of a pavement when subjected to polishing wear and loss of macrotexture caused by traffic with passage of time.1.4.4 Evaluating changes in the braking friction forces of a pavement contaminated with ice, moderate amounts2 of slush and snow, pollen, vehicle oil spills and condensates from vehicle engine exhaust, and deposits from other pollution sources.1.4.5 Evaluating the braking friction forces of a specimen tire on a clean or contaminated pavement.1.5 The friction values reported by this test method are insufficient to determine the distance required to stop a vehicle on either a dry, wet, or contaminated pavement. They are also insufficient for determining the speed at which control of a vehicle would be lost.1.6 The values stated in either SI units or inch-pound units 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 nonconformance with the standard.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. Specific precautionary statements are given in Section 6 and Note 4.1.8 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 procedure can be used to limit the need for screening tests prior to performing a test for estimating the LC50 of a non-reactive and non-electrolytic chemical to the fathead minnow. By eliminating the screening test, fewer fish need be tested. The time used for preparing and performing the screening test can also be saved. The value obtained in this procedure can be used as the preliminary estimate of the LC50 in a full-scale test.5.2 Estimates can be used to set testing priority of groups of non-reactive and non-electrolytic chemicals.5.3 If the estimated value is more than 0.3 times the experimental value, the mechanism of action is probably narcosis. If less, the effect concentration is considered to reflect a different mechanism of action.5.4 This practice estimates a maximum LC50, that is, non-reactive and non-electrolytic chemicals are at least as toxic as the practice predicts, but may have a lower LC50 if acting by a more specific mechanism. Data on a chemical indicating a lower toxicity than predicted should be considered suspect or an artifact because of limited solubility of the test material.1.1 This practice covers a procedure for estimating the fathead minnow (Pimephales promelas) 96-h LC50 of nonreactive (that is, covalently bonded without unsaturated residues) and nonelectrolytic (that is, require vigorous reagents to facilitate substitution, addition, replacement reactions and are non-ionic, non-dissociating in aqueous solutions) organic chemicals acting solely by narcosis, also referred to as Meyer-Overton toxicity relationship.21.2 This procedure is accurate for organic chemicals that are toxic due to narcosis and are non-reactive and non-electrolytic. Examples of appropriate chemicals are: alcohols, ketones, ethers, simple halogenated aliphatics, aromatics, and aliphatic substituted aromatics. It is not appropriate for chemicals whose structures include a potential toxiphore (that structural component of a chemical molecule that has been identified to show mammalian toxicity, for example CN is known to be reponsible for inactivation of enzymes, NO2 for decoupling of oxidative phosphorylation, both leading to mammalian toxicity). Examples of chemicals inappropriate for this practice are: carbamates, organophosphates, phenols, beta-gamma unsaturated alcohols, electrophiles, and quaternary ammonium salts.1.3 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—Leaky Aquifer: 5.1.1 Drawdown (sW) in the control well is constant,5.1.2 Well is infinitesimal diameter and fully penetrates aquifer,5.1.3 The aquifer is homogeneous, isotropic, and areally extensive, and5.1.4 The control well is 100 % efficient.5.2 Assumptions—Nonleaky Aquifer: 5.2.1 Drawdown (sW) in the control well is constant,5.2.2 Well is infinitesimal diameter and fully penetrates aquifer,5.2.3 The aquifer is homogeneous, isotropic, and areally extensive,5.2.4 Discharge from the well is derived exclusively from storage in the nonleaky aquifer, and5.2.5 The control well is 100 % efficient.5.3 Implications of Assumptions: 5.3.1 The assumptions are applicable to confined aquifers and fully penetrating control wells. However, this practice may be applied to partially penetrating wells where the method may provide an estimate of hydraulic conductivity for the aquifer adjacent to the open interval of the well if the horizontal hydraulic conductivity is significantly greater than the vertical hydraulic conductivity.5.3.2 Values obtained for storage coefficient are less reliable than the values calculated for transmissivity. Storage coefficient values calculated from control well data are not reliable.NOTE 7: 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 an analytical solution for determining transmissivity and storage coefficient of a leaky or nonleaky confined aquifer. It is used to analyze data on the flow rate from a control well while a constant head is maintained in the well.1.2 This analytical procedure is used in conjunction with the field procedure in Practice D5786.1.3 Limitations—The limitations of this technique for the determination of hydraulic properties of aquifers are primarily related to the correspondence between field situation and the simplifying assumption of the solution.1.4 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.1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.6 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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1.1 This test method covers the determination of sliding (kinetic) friction of plastic solids or sheeting (as moving specimens) when sliding against similar or dissimilar substances (Note 1) (as fixed specimens) through the speed range of approximately 0.10 to 3.00 m/s. The instrument used is a variable speed, variable normal-force frictionometer. , Note 1-The physical form for these fixed specimens should be that of rigid or self-supporting solids. Attempts to mount thin sheeting, film, foil, etc., are not recommended due to the difficulty encountered when attempting to meet the weight and concentricity requirements (see 4.1.1). 1.2 Rigid or self-supporting specimens must be machined to specified dimensions. Normally, sheeting exceeding 1.00 mm (0.040 in.) in thickness should not be tested on a mounting wheel of standard diameter. Note 2-An error accumulation of 1% per 0.50 mm (0.020 in.) of sheeting thickness results as the standard diameter of the test surface is increased. If the resulting error is not tolerable, undersize mounting wheels can be employed. 1.3 Two testing procedures are included. Selection of a procedure is determined by the specific interests of the investigator. The procedures are: 1.3.1 Procedure A -Determination of variable-velocity kinetic coefficients, and 1.3.2 Procedure B -Determination of constant-velocity kinetic coefficients over an extended period of time. 1.4 Test data obtained by this test method is relevant and appropriate for use in engineering design. 1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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 and health practices and determine the applicability of regulatory limitations prior to use .

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5.1 The purpose of these tests is to obtain, by means of simple apparatus, reliable and easy to determine values of liquid water transport for capillary active materials expressed in suitable units. These values are for use as part of the material properties in hygrothermal analysis tools for building envelope design and forensic studies. As the topic of liquid transport phenomena in porous materials is very complex, Appendix X1 in ISO 15148 shows some more detailed background information.1.1 This test method defines a procedure to determine the water absorption coefficient of a material by partial submersion. The scope is to evaluate the rate of absorption of water due to capillary forces for building materials in contact with normal or driving rain above grade. The procedure is typically suitable mainly for masonry material, plaster, or a coating in combination with a substrate; but it can also be used for insulation materials. This test method is designed to be used only on homogeneous materials and does not apply to materials that are composites or non-homogeneous (for example, Faced Rigid Closed-cell Insulation). It is not within the scope of this standard to determine liquid uptake phenomena in below-grade applications. The water absorption coefficient is mainly used as an input datum for numerical simulation of the combined heat and moisture transport in building envelopes for design and forensic investigation purposes.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. However, derived results can be converted from one system to the other using appropriate conversion factors (see Table 1).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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