分享
ASTM_D_5785_-_D_5785M_-_20.pdf
下载文档

ID:175618

大小:166.17KB

页数:6页

格式:PDF

时间:2023-03-04

收藏 分享赚钱
温馨提示:
1. 部分包含数学公式或PPT动画的文件,查看预览时可能会显示错乱或异常,文件下载后无此问题,请放心下载。
2. 本文档由用户上传,版权归属用户,汇文网负责整理代发布。如果您对本文档版权有争议请及时联系客服。
3. 下载前请仔细阅读文档内容,确认文档内容符合您的需求后进行下载,若出现内容与标题不符可向本站投诉处理。
4. 下载文档时可能由于网络波动等原因无法下载或下载错误,付费完成后未能成功下载的用户请联系客服处理。
网站客服:3074922707
TM_D_5785_ _D_5785M_ _20
Designation:D5785/D5785M20Standard Practice for(Analytical Procedure)for Determining Transmissivity ofConfined Nonleaky Aquifers by Underdamped WellResponse to Instantaneous Change in Head(Slug Test)1This standard is issued under the fixed designation D5785/D5785M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This practice covers determination of transmissivityfrom the measurement of the damped oscillation about theequilibrium water level of a well-aquifer system to a suddenchange of water level in a well.Underdamped response ofwater level in a well to a sudden change in water level ischaracterized by oscillatory fluctuation about the static waterlevel with a decrease in the magnitude of fluctuation andrecovery to initial water level.Underdamped response mayoccur in wells tapping highly transmissive confined aquifersand in deep wells having long water columns.1.2 This analytical procedure is used in conjunction with thefield procedure Test Method D4044/D4044M for collection oftest data.1.3 LimitationsSlug tests are considered to provide anestimate of transmissivity of a confined aquifer.This testmethod requires that the storage coefficient be known.As-sumptions of this practice prescribe a fully penetrating well(awell open through the full thickness of the aquifer),but the slugtest method is commonly conducted using a partially penetrat-ing well.Such a practice may be acceptable for applicationunder conditions in which the aquifer is stratified and horizon-tal hydraulic conductivity is much greater than vertical hydrau-lic conductivity.In such a case the test would be considered tobe representative of the average hydraulic conductivity of theportion of the aquifer adjacent to the open interval of the well.The method assumes laminar flow and is applicable for a slugtest in which the initial water-level displacement is less than0.1 or 0.2 of the length of the static water column.1.4 This practice for analysis presented here is derived byvan der Kamp(1)2based on an approximation of the under-damped response to that of an exponentially damped sinusoid.A more rigorous analysis of the response of wells to a suddenchange in water level by Kipp(2)indicates that the methodpresented by van der Kamp(1)matches the solution of Kipp(2)when the damping parameter values are less than about 0.2and time greater than that of the first peak of the oscillation(2).1.5 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues in each system may not be exact equivalents;thereforeeach system shall be used independently of the other.Combin-ing values from the two systems may result in non-conformance with the standard.Reporting of test results inunits other than SI shall not be regarded as nonconformancewith this practice.1.6 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.7 This practice offers a set of instructions for performingone or more specific operations.This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgment.Not all aspects of the practice maybe applicable in all circumstances.This ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a given professional service must be judged,nor should this document be applied without the considerationof a projects many unique aspects.The word“Standard”inthe title of this document means only that the document hasbeen approved through the ASTM consensus process.1.8 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone Investigations.Current edition approved May 15,2020.Published May 2020.Originallyapproved in 1995.Last previous edition approved in 2015 as D5785 15.DOI:10.1520/D5785_D5785M-20.2The boldface numbers given in parentheses refer to a list of references at theend of the text.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Har

此文档下载收益归作者所有

下载文档
你可能关注的文档
收起
展开