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5.1 The quality of the stripe for visibility in daylight or under road lighting is determined by the luminance coefficient under diffuse illumination, Qd, and depends on the materials used, age, and wear pattern. These conditions shall be observed and noted by the user.5.2 Under the same conditions of illumination and viewing, higher levels of Qd correspond to higher levels of lightness.5.3 Reflectivity of pavement (road) markings degrade with traffic wear and require periodic measurement to ensure that sufficient line visibility is provided to drivers.5.4 For a given viewing distance, measurements of Qd made with a reflectometer having a geometry corresponding to that distance are a good indicator of the visual ranking of material measured.5.5 specified by CEN, the measurement geometry of the instrument is based on a viewing distance of 30 m and an eye height of 1.2 m.5.6 It shall be the responsibility of the user to employ an instrument having the specified co-viewing angle.1.1 This test method covers measurement of the luminance coefficient under diffuse illumination of horizontal pavement markings, such as traffic stripes and surface symbols, and pavement surfaces, in a particular viewing direction using a portable reflectometer.NOTE 1: The luminance coefficient under diffuse illumination is a measure of the reflection of horizontal pavement markings and pavement surfaces in a particular viewing direction in daylight or under road lighting. Diffuse illumination approximates daylight illumination from the overcast sky, and road lighting as an average of locations on the pavement surface.1.2 The co-viewing angle of the reflectometer affects the readings. As specified by the European Committee for Standardization (CEN), the co-viewing angle shall be 2.29°.1.3 This test method is intended to be used for field measurement of pavement markings and pavement surfaces but may be used to measure the performance of materials on sample panels before placing the marking material in the field.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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5.1 This non-proprietary laboratory test method allows for the reproducible testing of whole footwear and footwear-related soling materials for evaluating relative slip performance. Other ASTM test methods generally employ a standardized test foot primarily for evaluation of flooring materials.1.1 This test method2 determines the dynamic coefficient of friction between footwear and floorings under reproducible laboratory conditions for evaluating relative slip performance. The method is applicable to all types of footwear, outsole units, heel top lifts and sheet soling materials, also to most types of floorings, including matting and stair nosing, and surface contaminants on the flooring surface, including but not limited to liquid water, ice, oil and grease. The method may also be applied to surfaces such as block pavers, turf and gravel.1.2 Special purpose footwear or fittings containing spikes, metal studs or similar may be tested on appropriate surfaces but the method does not fully take account of the risk of tripping due to footwear/ground interlock.1.3 The values stated in the ASTM test method in metrics are to be regarded as the standard. The values in parentheses are for information.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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定价: 590元 / 折扣价: 502 加购物车

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定价: 590元 / 折扣价: 502 加购物车

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5.1 Measurements made by this test method are related to visual observations of retroreflective sheeting as seen by the human eye when illuminated by tungsten-filament light sources such as a motor vehicle headlamp.5.2 The values determined relate to the visual effects for a given geometric configuration as specified by the user of the test method. This test method has been found useful for tests at observation angles between 0.1 and 2.0° (observation angles between 0.1° and 0.2° may be achieved by careful design of source and receiver aperture configuration), and at entrance angles up to 60°. It has been used to determine coefficient of retroreflection values as low as 0.1 cd·lx−1 · m−2, but for values less than 1 cd·lx−1 · m−2 special attention must be given to the responsivity of the receiver and to the elimination of very small amounts of stray light.1.1 This test method describes an instrument measurement of the retroreflective performance of retroreflective sheeting.1.2 The user of this test method must specify the entrance and observation angles to be used, and may specify the rotation angles.1.3 This test method is intended as a laboratory test and requires a facility that can be darkened sufficiently so that stray light does not affect the test results. The testing apparatus must be able to achieve the coplanar geometry.1.4 Portable and bench retroreflection measuring equipment may be used to determine RA values provided the geometry and appropriate substitution standard reference panels, measured in accordance with this test method, are utilized. In this case the methods of Procedure B in Practice E809 apply. Additional information on the use of portable retroreflectometers may be found in Test Method E1709.1.5 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.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 Assumptions: 5.1.1 The well discharges at a constant rate.5.1.2 Well is of infinitesimal diameter and is open through the full thickness of the aquifer.5.1.3 The nonleaky confined aquifer is homogeneous, isotropic, and areally extensive except where limited by linear boundaries.5.1.4 Discharge from the well is derived initially from storage in the aquifer; later, movement of water may be induced from a constant-head boundary into the aquifer.5.1.5 The geometry of the assumed aquifer and well are shown in Fig. 1 or Fig. 2.5.1.6 Boundaries are vertical planes, infinite in length that fully penetrate the aquifer. No water is yielded to the aquifer by impermeable boundaries, whereas recharging boundaries are in perfect hydraulic connection with the aquifer.5.1.7 Observation wells represent the head in the aquifer; that is, the effects of wellbore storage in the observation wells are negligible.5.2 Implications of Assumptions: 5.2.1 Implicit in the assumptions are the conditions of a fully-penetrating control well and observation wells of infinitesimal diameter in a confined aquifer. Under certain conditions, aquifer tests can be successfully analyzed when the control well is open to only part of the aquifer or contains a significant volume of water or when the test is conducted in an unconfined aquifer. These conditions are discussed in more detail in Practice D4105/D4105M.5.2.2 In cases in which this practice is used to locate an unknown boundary, a minimum of three observation wells is needed. If only two observation wells are available, two possible locations of the boundary are defined, and if only one observation well is used, a circle describing all possible locations of the image well is defined.5.2.3 The effects of a constant-head boundary are often indistinguishable from the effects of a leaky, confined aquifer. Therefore, care must be taken to ensure that a correct conceptual model of the system has been created prior to analyzing the test. See Guide D4043.NOTE 2: Slug and pumping tests implicitly assume a porous medium. Fractured rock and carbonate settings may not provide meaningful data and information.5.3 Practice D3740 provides evaluation factors for the activities in this standard.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 an analytical procedure for determining the transmissivity, storage coefficient, and possible location of boundaries for a confined aquifer with a linear boundary. This practice is used to analyze water-level or head data from one or more observation wells or piezometers during the pumping of water from a control well at a constant rate. This practice also applies to flowing artesian wells discharging at a constant rate. With appropriate changes in sign, this practice also can be used to analyze the effects of injecting water into a control well at a constant rate.1.2 The analytical procedure in this practice is used in conjunction with the field procedure in Test Method D4050.1.3 Limitations—The valid use of this practice is limited to determination of transmissivities and storage coefficients for aquifers in hydrogeologic settings with reasonable correspondence to the assumptions of the Theis nonequilibrium method (see Practice D4106) (see 5.1), except that the aquifer is limited in areal extent by a linear boundary that fully penetrates the aquifer. The boundary is assumed to be either a constant-head boundary (equivalent to a stream or lake that hydraulically fully penetrates the aquifer) or a no-flow (impermeable) boundary (equivalent to a contact with a significantly less permeable rock unit). The Theis nonequilibrium method is described in Practices D4105/D4105M and D4106.1.4 Units—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. Reporting of 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 D6026.1.6 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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