ImageVerifierCode 换一换
格式:PDF , 页数:4 ,大小:74.39KB ,
资源ID:170797      下载积分:13 积分
快捷下载
登录下载
邮箱/手机:
温馨提示:
快捷下载时,用户名和密码都是您填写的邮箱或者手机号,方便查询和重复下载(系统自动生成)。 如填写123,账号就是123,密码也是123。
特别说明:
请自助下载,系统不会自动发送文件的哦; 如果您已付费,想二次下载,请登录后访问:我的下载记录
支付方式: 支付宝扫码支付 微信扫码支付   
验证码:   换一换

加入VIP,免费下载
 

温馨提示:由于个人手机设置不同,如果发现不能下载,请复制以下地址【https://www.wnwk.com/docdown/170797.html】到电脑端继续下载(重复下载不扣费)。

已注册用户请登录:
账号:
密码:
验证码:   换一换
  忘记密码?
三方登录: QQ登录  

下载须知

1: 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。
2: 试题试卷类文档,如果标题没有明确说明有答案则都视为没有答案,请知晓。
3: 文件的所有权益归上传用户所有。
4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
5. 本站仅提供交流平台,并不能对任何下载内容负责。
6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

版权提示 | 免责声明

本文(ASTM_D_7238_-_06_2012.pdf)为本站会员(益****师)主动上传,蜗牛文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知蜗牛文库(发送邮件至admin@wnwk.com或直接QQ联系客服),我们立即给予删除!

ASTM_D_7238_-_06_2012.pdf

1、Designation:D723806(Reapproved 2012)Standard Test Method forEffect of Exposure of Unreinforced PolyolefinGeomembrane Using Fluorescent UV CondensationApparatus1This standard is issued under the fixed designation D7238;the number immediately following the designation indicates the year oforiginal ado

2、ption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This standard covers the specific procedures and testconditions that are appli

3、cable for exposure of unreinforcedpolyolefin geomembranes to fluorescent UV radiation andcondensation.NOTE1Polyolefin geomembranes include high density polyethylene(HDPE),linear low density polyethylene(LLDPE),flexible polyproply-ene(fPP),etc.1.2 Test specimens are exposed to fluorescent UVA 340lamp

4、s under controlled environmental conditions.UVA 340lamps are standard for this method.NOTE2Other types of fluorescent UV lamps,such as UVB-313,canalso be used based upon discussion between involved parties.However,ifthe test is ran with another type of fluorescent UV lamps,such asUVB-313,this should

5、 be considered as a deviation from the standard andclearly stated in the test report.UVB-313 and UVA-340 fluorescent lampsgenerate different amount of radiant power in different wavelength ranges;thus,the photochemical effects caused by these different lamps may vary.1.3 This method covers the condi

6、tions under which theexposure is to be performed and the test methods for evaluatingthe effects of fluorescent UV,heat and moisture in the form ofcondensation on geomembranes.General guidance is given inPractices G151 and G154.1.4 The values listed in SI units are to be regarded as thestandard.1.5 T

7、his 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2

8、.1 ASTM Standards:2D1238 Test Method for Melt Flow Rates of Thermoplasticsby Extrusion PlastometerD5885 Test Method for Oxidative Induction Time of Poly-olefin Geosynthetics by High-Pressure Differential Scan-ning CalorimetryD6693 Test Method for Determining Tensile Properties ofNonreinforced Polyet

9、hylene and Nonreinforced FlexiblePolypropylene GeomembranesG113 Terminology Relating to Natural and Artificial Weath-ering Tests of Nonmetallic MaterialsG151 Practice for Exposing Nonmetallic Materials inAccel-erated Test Devices that Use Laboratory Light SourcesG154 Practice for Operating Fluoresce

10、nt LightApparatus forUV Exposure of Nonmetallic MaterialsG156 Practice for Selecting and Characterizing WeatheringReference Materials3.Terminology3.1 Definitions:(According to Terminology G113).3.1.1 control,nAmaterial which is of similar compositionand construction to the test material used for com

11、parison,exposed at the same time.3.1.2 irradiance,nthe radiant power per unit area incidenton a receiver,typically reported in units of W/(m2.nm)atspecified wavelength of measurement or in W/m2in a specifiedspectral range.3.1.3 reference material,nA material with known perfor-mance.3.1.4 ultraviolet

12、 regions,nThe UV region of the spectrumis divided into three regions:UVA,radiation in wavelengths1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.02 on Endur-ance Properties.Current edition approved July 1,2012.Pub

13、lished July 2012.DOI:10.1520/D7238-06R20122For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM Internati

14、onal,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 between 315 nm and 400 nm;UVB,radiation in wavelengthsbetween 280 nm and 315 nm;and UVC,radiation in wave-lengths shorter than 280 nm(Ref.CIE Publication No.20(1972).4.Summary of Test Method4.1 Geomembrane coupons

15、are exposed to repetitive cyclesconsisting of ultraviolet radiation at a specified temperaturefollowed by moisture in the form of condensation at a specifiedtemperature in the absence of ultraviolet radiation.4.2 The UV source is provided by fluorescent UVA-340lamps,with lamp emissions peaking at 34

16、3 nm.4.3 Water vapor shall be generated by heating water andfilling the chamber with hot vapor,which then is made tocondense on the front of the test coupons.The reverse side ofthe coupons is exposed to the cooling influence of ambientroom air.4.4 While this standard prescribes a particular set of expo-sure conditions,such conditions may be varied by agreementbetween the parties involved in the agreement or contract.Suchvariation may include the irradiance,the selection of thefluorescent UV lamp

copyright@ 2008-2023 wnwk.com网站版权所有

经营许可证编号:浙ICP备2024059924号-2