Astm stp 1190 1993

STP 1190 Geosynthetic Soil Reinforcement Testing Procedures S C Jonathan Cheng, editor ASTM Publication Code Number (PCN) 04-011900-38 1916 Race Street Philadelphia, PA 19103 Library of Congress Cataloging-ln-Publication Data Geosynthetic soil reinforcement testing procedures / S.C Jonathan Cheng, editor (STP ; 1190) Includes bibliographical references and index ISBN 0-8031-1885-6 i Soil stabilization Testing Geosynthetics Testing I Cheng, S C Jonathan (Shi-Chieh Jonathan) If Series: ASTM special technical publication ; 1190 TATI0.5.G44 1993 624.1'51363 dc20 93-8893 CIP Copyright 1993 AMERICAN SOCIETY FOR TESTING AND MATERIALS, Philadelphia, PA All rights reserved This material may not be reproduced or copied, in whole or in part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of the publisher Photocopy Rights Authorization to photocopy items for internal or personal use, or the internal or personal use of specific clients, is granted by the AMERICAN SOCIETY FOR TESTING AND MATERIALS for users registered with the Copyright Clearance Center (CCC) Transactional Reporting Service, provided that the base fee of $2.50 per copy, plus $0.50 per page is paid directly to CCC, 27 Congress St., Salem, MA 01970; (508) 744-3350 For those organizations that have been granted a photocopy license by CCC, a separate system of payment has been arranged The fee code for users of the Transactional Reporting Service is 0-8031-1885-6/93 $2.50 + 50 Peer Review Policy Each paper published in this volume was evaluated by three peer reviewers The authors addressed all of the reviewers' comments to the satisfaction of both the technical editor(s) and the ASTM Committee on Publications To make technical information availableas quickly as possible, the peer-reviewed papers in this publication were printed "camera-ready," as submitted by the authors The quality of the papers in this publication reflects not only the obvious efforts of the authors and the technical editor(s), but also the work of these peer reviewers The ASTM Committee on Publications acknowledges with appreciation their dedication and contribution to time and effort on behalf of ASTM Prinled in Fredericklburg, VA August 1993 Foreword This publication, GeosyntheticSoilReinforcement TestingProcedures, contains papers presented at the symposium of the same name, held in San Antonio, TX on 19 Jan 1993 The symposium was sponsored by ASTM Committee D-35 on Geosynthetics S C Jonathan Cheng of Drexel University in Philadelphia, PA, presided as symposium chairman and is the editor of the resulting publication Contents Overview s c JONATHANCHENG vii A New Device for Evaluating Load-Transfer in Geosynthetic Reinforced Soils-A J WHITTLE, D G.LARSON, J T GERMAINE, AND M ABRAMENTO Intrinsic Confined and Unconfined Load-Deformation Properties of Geotextiles-J P BALLEGEER AND J T H WU Laboratory Testing of Modular Masonry Concrete Biock-Geogrid Facing Connections g J BATHURST AND M.R SIMAC 16 32 Unconfined and Confined Wide Width Tension Testing of Geosynthetics-R F WILSON-FAHMY, R M KOERNER, AND J A FLECK 49 Index and Performance Tests for Geocelis in Different Applications A PANCELLI, P RIMOLDI, AND F MONTANELLI 64 Pull-Oat Testing of Geogrids in Cohesive Soils K A FARRAGAND P GRIFFIN 76 The Influence of Test Parameters and Procedures on the Tensile Modulus of Still Geogrids D N AUSTIN, K J WU, AND D F WHITE 90 High Strength Polyester Geotexile Testing and Material Property Evaluation-J N PAULSON 111 Laboratory Investigations on the Shear Strength of Geogrid Reinforced Soils-D CAZZUFFI, L PICARELLI, A RICCIUTI, AND P RIMOLDI Evaluation of Shear Strength and Dilatancy Behavior of Reinforced Soil from Direct Shear Tests G E BAUERAND Y ZHAO 119 138 Material Parameters Used in Design of Geosynthetic Reinforced Soil Structures-R R BERG AND J G COLLIN 152 Geosynthetic Installation Damage under Two Different Backfill Conditions-G R KOERNER, R M K O E R N E R , AND V ELIAS Comparison of Short-Term and Long-Term Pullout Testing of Geogrid Reinforcements J G COLLIN AND R R BERG 163 184 Pullout Resistance and Load-Slip Response of Mechanically Damaged Geogrids-A G R A Z A Q P U R , G E BAUER, A O A HALIM, A N D Y Z H A O 195 Chemical Stability of Polyester Fibers and Geotextiles Without and Under Stress A N NETRAVALI, R KRSTIC, J L CROUSE, AND L E RICHMOND 207 Testing for Biological Deterioration of Geosynthetics in Soil Reinforcement and Stabilization D G ngIGHX 218 A Review of the Degradation of Geosynthetic Reinforcing Materials and Various Polymer Stabilization Methods ',' G HSUAN,R M KOERNER,AND A E LORD, JR 228 Author Index 245 Subject Index 247 Overview This ASTM symposium provides a forum for presentation of state-of-the-art technologies and new developments in geosynthetic soil reinforcement testing The topics addressed include mechanical and durability properties with respect to the reinforcement function of geosynthetics, analysis of reinforcement testing results, and evaluation of testing results in relation to design This symposium was also a result of an ASTM Committee D-35 seminar held in June 1991, concerning the same topic of geosynthetic soil reinforcement testing Since the use of geosynthetics in reinforcement applications is rapidly increasing, there is a need to institute a rational technical base for an understanding of the performance ofgeosynthetics in reinforcement applications The corner stone of this technical base is the timely development of standardizing test methods, that is the charter of Committee D-35 on Geosynthetics Although much progress has been witnessed as more testing methods are made available through ASTM processes, there is a significant lag betwen the state-of-the-art and present standardized test methods This symposium attempts to provide a bridge between this time gap The organization of this Special Technical Publication (STP) is as follows: (1) Papers associated with either new testing equipment/procedures, or testing procedures for new reinforcement applications are included These papers provide direction in the development of standard testing methods (papers through 5) (2) Papers evaluating procedures of testing methods that are standardized or widely used are also included The discussions are focused on those factors that influence test results (papers through 10) (3) The next section of papers are concerned with the analysis of testing results in relation to design In terms of standard practice, this is an area of need within ASTM (papers 11 through 14) (4) Finally, papers associated with the durability issue of geosynthetic reinforcement applications conclude this STP (papers 15 through 17) All of the papers in this STP went through a rigorous review process I would like to extend my most sincere appreciation to the authors for their enthusiastic participation and to the reviewers for their professional critiques My work as editor of this publication has been very rewarding, but the credit must go to the authors and reviewers In addition, I would like to thank the administrative support group from ASTM, especially Mrs Dorothy Savini, Ms Rita Hippensteel, and Mrs Therese Pravitz This symposium is a step towards fully understanding the technical performance ofgeosynthetics It is my most sincere hope that it will catalyze further research work and technical advancement Shi-Chieh Cheng Drexel University, Philadelphia, PA; symposium chairman and editor vii A n d r e w J W h i t t l e I, Douglas Abramento I A NEW DEVICE FOR REINFORCED SOILS R E F E R E N C E : Whittle, M "A N E W DEVICE REINFORCED SOILS," Procedures, for T e s t i n g G Larson I, John EVALUATING A.J., FOR Larson, T Germaine I and M a u r i c i o LOAD-TRANSFER D.G., EVALUATING IN Germaine, LOAD-TRANSFER GEOSYNTHETIC J.T IN a n d Abramento, GEOSYNTHETIC Geosvnthe~ic Soil R e i n f o r c ~ m ~ n t T e s t i n q A S T ~ STP 1190, 5.C Jonathan Cheng, Ed., A m e r i c a n and Materials, Philadelphia, 1993 Society A l t h o u g h g e o s y n t h e t i c s are often used in soil r e i n f o r c e m e n t applications, there are c u r r e n t l y no m e t h o d s for e s t i m a t i n g reliably the stresses w i t h i n the reinforcements at w o r k i n g load levels This paper summarizes the design of a new laboratory device, r e f e r r e d to as the A u t o m a t e d Plane Strain Reinforcement (APSR) cell, which m e a s u r e s the m a x i m u m tensile stress that develops at the center of a single p l a n a r i n c l u s i o n due to shearing of the s u r r o u n d i n g soil The cell can a c c o m o d a t e a wide range of reinforcing m a t e r i a l s and can be e q u i p e d with a d d i t i o n a l i n s t r u m e n t a t i o n to measure the d i s t r i b u t i o n of strains and/or stresses with inclusions of h a l f - l e n g t h s up to 450mm Test data, o b t a i n e d for an i n s t r u m e n t e d steel sheet i n c l u s i o n e m b e d d e d in Ticino sand, d e m o n s t r a t e the capabilities of the A P S R cell for m e a s u r i n g loadt r a n s f e r at w o r k i n g load levels Simple c l o s e d form solutions b a s e d on shear lag analysis describe accurately the tensile stresses m e a s u r e d in the e l a s t i c steel sheet inclusion The new device p r o v i d e s the c a p a b i l i t y to compare load-transfer c h a r a c t e r i s t i c s for different classes of g e o s y n t h e t i c reinforcing materials ABSTRACT: K E Y W O R D S : New plane strain test, p l a n a r reinforcement, measurement, shear lag analysis, sand-steel data tensile stress INTRODUCTION High strength polymer grids and strips, woven and n o n - w o v e n fabrics are widely used to reinforce soil masses in the c o n s t r u c t i o n of r e t a i n i n g walls, embankments, foundations and pavements The p e r f o r m a n c e of these c o m p o s i t e soil structures depends, in large part, on the i n t e r a c t i o n b e t w e e n the soil matrix a n d the inclusions w h i c h determines the m a g n i t u d e of loads c a r r i e d by the reinforcement The m e c h a n i s m s of i n t e r a c t i o n are p a r t i c u l a r l y complex for reinforcements w i t h n o n - p l a n a r IAssistant Professor, Research Assistant, Principal and R e s e a r c h Assistant, respectively, M a s s a c h u s e t t s Technology, Cambridge, MA 02139~ Copyright 1993 by ASTM International www.astm.org Research Associate Institute of GEOSYNTHETICSOIL REINFORCEMENTTESTINGPROCEDURES surfaces, such as grids and for g e o s y n t h e t i c m a t e r i a l s which exhibit n o n - l i n e a r and/or time dependent behavior E x i s t i n g analyses of soilreinforcement interaction focus m a i n l y on ultimate limit c o n d i t i o n s using h o m o g e n i z a t i o n or limit e q u i l i b r i u m methods H o m o g e n i z a t i o n methods [!] typically assume that the soil mass is r e i n f o r c e d with uniform, closely spaced inclusions and can be a n a l y z e d (at the m a c r o s c o p i c level) as an homogeneous, a n i s o t r o p i c c o m p o s i t e material Failure of composite r e i n f o r c e d soils has been i n v e s t i g a t e d e x p e r i m e n t a l l y from m e a s u r e m e n t s of b o u n d a r y t r a c t i o n s and d i s p l a c e m e n t s in a variety of laboratory shear tests [~, ~] These data show that the reinforcelnents produce an apparent cohesive s t r e n g t h c o m p o n e n t that is d i r e c t l y p r o p o r t i o n a l to the d e n s i t y and strength of the inclusions However, m e a s u r e m e n t s in laboratory tests cannot be scaled reliably to field situations which are g e n e r a l l y c h a r a c t e r i z e d by a r e l a t i v e l y small number of reinforcing layers Current design methods for r e i n f o r c e d soil m a s s e s are g e n e r a l l y based on limit e q u i l i b r i u m analyses [~] which p o s t u l a t e d i f f e r e n t m e c h a n i s m s of failure and require input p a r a m e t e r s to c h a r a c t e r i z e the b o n d resistance b e t w e e n the soil and reinforcement in two modes: i) direct shearing along the soil-reinforcement interface, and 2) tensile a n c h o r a g e within the stable soil mass These p a r a m e t e r s are u s u a l l y o b t a i n e d from laboratory direct shear box (interface) and pullout tests, respectively The m e a s u r e m e n t s suffer from a n u m b e r of well known p r a c t i c a l limitations associated with poorly c o n t r o l l e d test boundary conditions and are especially difficult to interpret for relatively e x t e n s i b l e reinforcements (including many geosynthetics) and for inclusions with non-planar surfaces M o r e c o m p r e h e n s i v e studies of s o i l - r e i n f o r c e m e n t i n t e r a c t i o n are n e c e s s a r y to u n d e r s t a n d the stress d i s t r i b u t i o n w i t h i n a r e i n f o r c e d soil mass at w o r k i n g load conditions In principle, c o m p r e h e n s i v e stress analyses can be a c h i e v e d using n o n - l i n e a r finite element (or b o u n d a r y element) methods which model e x p l i c i t l y the c o n s t i t u t i v e p r o p e r t i e s of the soil, reinforcement and interfaces A l t h o u g h these analyses offer great flexibility for simulating complex p r o b l e m geometries, c o n s t r u c t i o n histories, etc., it is difficult to interpret the u n d e r l y i n g m e c h a n i s m s of soil-reinforcement i n t e r a c t i o n from complex n u m e r i c a l analyses In contrast, this paper d e s c r i b e s the d e v e l o p m e n t of a simple analytical framework for p r e d i c t i n g and i n t e r p r e t i n g tensile stresses in a p l a n a r inclusion due to shearing of the s u r r o u n d i n g soil The analysis considers plane strain c o m p r e s s i o n s h e a r i n g of the soil mass w i t h the inclusion oriented p a r a l l e l to the minor, external p r i n c i p a l stress These studies provide the basis for the d e s i g n of a new laboratory apparatus, referred to as the A P S R cell, which is capable of m e a s u r i n g directly the tensile stresses within the reinforcement and imposes well d e f i n e d boundary conditions on the soil specimen M e a s u r e m e n t s in the A P S R cell provide a m e t h o d for c o m p a r i n g loadt r a n s f e r c h a r a c t e r i s t i c s for different types of g e o s y n t h e t i c reinforcements TENSILE STRESSES IN A PLANAR REINFORCEMENT Figure shows the idealized geometry for a composite plane strain element of reinforced soil which comprises a planar i n c l u s i o n of thickness, f, and length, L, e m b e d d e d in a soil m a t r i x of overall height, m+f (corresponding to the typical inclusion spacing) The o r i e n t a t i o n of the inclusion is parallel to the minor, external, p r i n c i p a l stress acting on the soil matrix, ~3- The soil is sheared in a WHITTLE ET AL ON EVALUATING LOAD-TRANSFER plane strain compression mode by increasing the major principal stress, ~I, at the boundary of the element (with ~3 constant) For these loading conditions, the inclusion reduces the lateral tensile strains which would otherwise develop in the soil and hence, represents the optimal orientation for a planar tensile reinforcement Abramento and Whittle [~] have adapted technqiues of 'shear lag' analyses, widely used in the mechanics of composites [~, ~, ~], in order to derive approximate analytical expressions for the tensile stresses in the reinforcement, G~x Initially these analyses have assumed the following: i The soil matrix and reinforcement behave as linear, isotropic and elastic materials (with properties Gm, V m and El, vf, respectively, Fig i) It should be noted that deformation properties of the soil (and also some non-woven geosynthetic materials) are dependent on the confining stress level The soil matrix and reinforcing inclusion are linked through a frictional interface, described by an angle of interface friction, There is no axial stress acting at the ends of the reinforcement, (i.e ~ x = at x=• as the inclusion is thin and is not physically bonded to the soil matrix Y (5 :::::::::::::::::::::::::::::::::::::::::::::::::::::::: ::::::::::::::::::::::::::::::::::::::::::::::: : ~ - m+f x liili!iiiiiiiiiiiiiiiiiiiiiiii i iIiiiiiiliill li)lii;iiiill t t t t Reinforcement E[, vf FIG Geometry of the reinforced soil element For the case where there is no slippage at the soil-reinforcement interface, the tensile stress in the reinforcement can be written as a linear function of the external principal stresses sl and ~3: ~x where, = ~ I K~ Ii c~ K ~ i c o Ks ~h I ~ I (i) HSUAN ET AL ON GEOSYNTHETIC REINFORCING MATERIALS 233 (a) Nonannealed material 1.0 0.5 (b) Annealed Material 1.0 0.5 ~~] Time Fig Methods ~ = to l = d r a w ratio (log s c a l e ) Effect of a n n e a l i n g on the i n d u c t i o n (after r e f e r e n c e [17]) to M i n i m i z e period of o x i d a t i o n Oxidation Since the p r e v e n t i o n of o x y g e n m e e t i n g the s u r f a c e of g e o s y n t h e t i c m a t e r i a l is p r a c t i c a l l y impossible, m a n u f a c t u r e r s have d e v e l o p e d other m e t h o d s to m i n i m i z e o x i d a t i o n degradation For example, a n t i o x i d a n t s and c a r b o n b l a c k are r o u t i n e l y u s e d in the p o l y m e r blend Metal d e a c t i v a t o r s m a y also be added E a c h is b r i e f l y e x p l a i n e d (a~ A n t i o x i d a n t s A n t i o x i d a n t s are u s e d as a d d i t i v e s to c o u n t e r a c t the o x i d a t i o n reaction The a c t i v i t y is f o c u s e d in two stages: i n i t i a t i o n (Equations and 2) and p r o p a g a t i o n (Equations to 6) At the i n i t i a t i o n stage, the f u n c t i o n of an a n t i o x i d a n t is to scavenge (i.e., c h e m i c a l l y c o m b i n e with) the free radicals, c o n v e r t i n g t h e m into stable m o l e c u l e s At the p r o p a g a t i o n stage, the o x i d a t i v e product, ROOH, is the sole target The f u n c t i o n of the a n t i o x i d a n t s is to convert this h i g h l y r e a c t i v e h y d r o p e r o x i d e (ROOH) into a m o r e stable form, such as ROH A r e c e n t l y d e v e l o p e d a n t i o x i d a n t f a m i l y is H i n d e r e d A m i n e Light S t a b i l i z e r s (HALS) which are u s e d in m a n y g e o s y n t h e t i c materials (b) C a r b o n b l a c k The most w i d e l y u s e d light s t a b i l i z e r in g e o s y n t h e t i c m a t e r i a l s is c a r b o n black The p r i m a r y f u n c t i o n of carbon b l a c k is a light screen (reducing p e n e t r a t i o n of u l t r a v i o l e t r a d i a t i o n into the p o l y m e r matrix) W a l e r and J u z k o w [18] s h o w that 3% carbon b l a c k e n h a n c e s the p e r f o r m a n c e of c e r t a i n a n t i o x i d a n t s to a great extent, as shown in F i g u r e However, Roots [19] i n d i c a t e d that carbon b l a c k u s u a l l y reduces the heat s t a b i l i t y of the polymer Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions author 234 GEOSYNTHETIC SOIL REINFORCEMENT TESTING PROCEDURES 50 o 40 o ~ 0.1% antioxidant 3% carbon black 30 0.1% antioxidant+ / o 20 N O i0 I 200 400 Time Fig 800 600 at 140~ I i000 hr S y n e r g i s t i c effect of an a n t i o x i d a n t a n d c a r b o n b l a c k on t h e r m a l o x i d a t i o n of p o l y e t h y l e n e ( A f t e r r e f e r e n c e 17) ,C3 M e t a l d e a c t i v a t o r s If t r a n s i t i o n m e t a l ions in the soil b e c o m e a concern, m e t a l d e a c t i v a t o r s can be a d d e d to c h e l a t e (i.e., to c a p t u r e and surround) the metal ions and reduce t h e i r c a t a l y t i c effect on the d e c o m p o s i t i o n of ROOH [20] The p o s s i b l e m e t a l d e a c t i v a t o r s are v a r i o u s oxamide d e r i v a t i v e s (RNHC=O) Suggested Methods for E v a l u a t i n a Oxidation M o s t or p r o b a b l y all g e o s y n t h e t i c p r o d u c t s m a d e f r o m p o l y o l e f i n s c o n t a i n some type of a n t i o x i d a n t H e n c e it is i m p o r t a n t to r e c o g n i s e that test m e t h o d s a i m e d at e v a l u a t i n g the t h e r m o x i d a t i v e s t a b i l i t y of p o l y o l e f i n s w o u l d m o s t likely c h a l l e n g e the l i f e t i m e of the a n t i o x i d a n t s in the p o l y m e r rather t h a n the s t a b i l i t y of the p o l y m e r itself In other words, the service life of the m a t e r i a l is p r o b a b l y d i c t a t e d by the e f f i c i e n c y of the a n t i o x i d a n t s If one wants to use a c c e l e r a t e d l a b o r a t o r y i n c u b a t i o n m e t h o d s to e v a l u a t e p e r f o r m a n c e and lifetime, an oven a g i n g p r o c e d u r e is recommended Test samples are p l a c e d in a f o r c e d air oven at d e s i r e d t e m p e r a t u r e s d e p e n d e n t on the type of polyolefin G r a y [21] u s e d 150~C for p o l y p r o p l y e n e and 120~ for p o l y e t h y l e n e A m i n i m u m of three d i f f e r e n t test t e m p e r a t u r e s should be u s e d to e v a l u a t e a given material A f t e r a specific time interval, the i n c u b a t e d s a m p l e s are r e m o v e d and t e s t e d so that the l i f e t i m e of the m a t e r i a l can be p r e d i c t e d u s i n g an e x t r a p o l a t i o n method, such as A r r h e n i u s M o d e l i n g [22] It is i m p o r t a n t to note that, for e v a l u a t i n g an o r i e n t e d product, the test t e m p e r a t u r e must be b e l o w the t e m p e r a t u r e at w h i c h the m a t e r i a l was s t r e t c h e d or oriented This will p r e s e r v e the dense p a c k e d s t r u c t u r e of the material, so that the test results will be m o r e realistic However, if s a m p l e s are b e i n g r e t r i e v e d f r o m the f i e l d in o r d e r to assess the d e g r e e Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions auth HSUAN ET AL ON GEOSYNTHETIC REINFORCING MATERIALS 235 of oxidation, t h e y s h o u l d be u t i l i z e d d i r e c t l y and n e e d not be incubated In e i t h e r case (laboratory or field), the f o l l o w i n g test m e t h o d s are r e c o m m e n d e d to e v a l u a t e the initial stages of d e g r a d a t i o n (Note that a wide range of more c o n v e n t i o n a l p h y s i c a l / m e c h a n i c a l tests can be u s e d to e v a l u a t e a d v a n c e d stages of d e g r a d a t i o n ) (a) O x i d a t i v e i n d u c t i o n time (conventional) O x i d a t i v e i n d u c t i o n time (OIT) of a p o l y m e r is m e a s u r e d u s i n g c o n v e n t i o n a l d i f f e r e n t i a l s c a n n i n g c a l o r i m e t e r (DSC) The OIT is the l e n g t h of time r e q u i r e d to d e c o m p o s e the p o l y m e r at 200~ u n d e r o x y g e n atmosphere The c l o s e s t r e l a t e d s t a n d a r d is A S T M D3895 The m e t h o d is often u s e d as a Q A / Q C test for c o n f i r m a t i o n p u r p o s e s or p o s s i b l y a test to m o n i t o r p o l y m e r aging However, the test s h o u l d not be u s e d for c o m p a r i n g p r o d u c t s with d i f f e r e n t a n t i o x i d a n t formulations, since OIT varies with d i f f e r e n t types of a n i t o x i d a n t s Some a n t i o x i d a n t s y i e l d a h i g h OIT value at 200~ but m a y not n e c e s s a r y p r o v i d e a long d u r a t i o n at the a m b i e n t temperature, and v i s a versa [21] The p r o b l e m with this test is the high test t e m p e r a t u r e at which the test p e c i m e n is in m o l t e n stage At that temperature, some a n t i o x i d a n t s m a y p e r f o r m v e r y p o o r l y but t h e y can f u n c t i o n v e r y well at the a m b i e n t t e m p e r a t u r e Since the m a t e r i a l is always u s e d at lower t e m p e r a t u r e s when it is solid, the i n t e r p r e t a t i o n of the results are very difficult (b} O x i d a t i v e i n d u c t i o n time (hioh pressure) In o r d e r to o v e r c o m e the h i g h test t e m p e r a t u r e of the c o n v e n t i o n a l test as d e s c r i b e d above, the test can also be p e r f o r m e d u n d e r h i g h p r e s s u r e in a high p r e s s u r e DSC cell at a t e m p e r a t u r e b e l o w 200~ C a d w a l l a d e r [23] has u s e d 5.5 MPa (800 psi) oxygen at t e m p e r a t u r e s of 180~ and 130~ for t e s t i n g HDPE g e o m e m b r a n e s His results show a b e t t e r d i s t i n c t i o n b e t w e e n d i f f e r e n t f o r m u l a t i o n s at 130~ but the test takes a m u c h longer time t h a n at 180~ In addition, the m e t h o d is c r i t i c i z e d b e c a u s e of the h i g h oxygen p r e s s u r e u s e d d u r i n g the test, since such a c o n d i t i o n w o u l d not be e n c o u n t e r e d in any real life situation The high p r e s s u r e m a y e v e n change the m e c h a n i s m of the d e g r a d a t i o n process (c) F o u r i e r t r a n s f o r m i n f r a r e d s p e c t r o s c o p y {FTIR} O n c e the a n t i o x i d a n t s have b e e n c o m p l e t e l y consumed, o x i d a t i o n starts to p r o p a g a t e in the polymer The result of the o x i d a t i o n of p o l y o l e f i n s is the f o r m a t i o n of c a r b o n y l group (C=O) in the p o l y m e r chains Such groups can be d e t e c t e d using FTIR The c h a r a c t e r i s t i c a b s o r p t i o n b a n d of this g r o u p is in the v i c i n i t y of 1735 cm -I [24] Since o x i d a t i o n first takes part at the surface a n d then g r a d u a l l y i n f i l t r a t e s into the material, the test is p e r f o r m e d u s i n g a r e f l e c t a n c e mode It allows the IR b e a m to be r e f l e c t e d f r o m the sample surface, s u b s e q u e n t e l y a n a l y z i n g the surface m a t e r i a l [25] (d) Gel p e r m e a t i o n c h r o m a t o o r a p h v (GPC) It was s t a t e d p r e v i o u s l y that o x i d a t i o n i n d u c e s chain s c i s s i o n l o w e r i n g the m o l e c u l a r weight and s u b s e q u e n t l y c h a n g e s the m o l e c u l a r weight d i s t r i b u t i o n curve of the polymer GPC is a unique t e c h n i q u e u s e d to a n a l y z e m o l e c u l a r weight d i s t r i b u t i o n of p o l y m e r i c m a t e r i a l s [26] However, for p o l y o l e f i n g e o s y n t h e t i c s m a t e r i a l s , high t e m p e r a t u r e GPC is required In addition, Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authoriz 236 GEOSYNTHETIC SOIL REINFORCEMENT TESTING PROCEDURES s i g n i f i c a n t amounts of f i l t r a t i o n b l a c k p a r t i c l e s f r o m the polymer HYDROLYSIS OF are n e e d e d to s e p a r a t e the c a r b o n POLYESTER One of the m a j o r concerns of g e o s y n t h e t i c r e i n f o r c e m e n t m a t e r i a l s m a d e f r o m p o l y e s t e r is the p o t e n t i a l l o n g - t e r m h y d r o l y t i c reaction The p a r t i c u l a r p o l y e s t e r u s e d to m a k e g e o t e x t i l e s and g e o g r i d s is p o l y e t h y l e n e t e r e p h t h a l a t e (PET) This c o m p o u n d is f o r m e d by a reaction b e t w e e n t e r e p h t h a l i c a c i d and e t h y l e n e glycol, as seen in E q u a t i o n 10 [27] n (HOOC - C6H - COOH) (Terephthalic HO + n (HOCH2CH2OH) acid) (Ethylene glycol) [-OC - C6H - C O O C H C H - ] n H (PET) + (i0) nH20 (water) This is an e q u i l i b r i u m r e a c t i o n in that w a t e r m u s t be c o n t i n u o u s l y r e m o v e d to a c h i e v e h i g h e f f i c i e n c y and a high m o l e c u l a r weight polymer It s h o u l d be r e c o g n i z e d that the r e a c t i o n can be reversed, i.e., PET p o l y m e r can react with water and revert to c o m p o u n d s w i t h a c i d or h y d r o x i d e e n d groups This r e v e r s e r e a c t i o n is the h y d r o l y t i c r e a c t i o n of PET, r e d u c i n g the m o l e c u l a r weight via chain s c i s s i o n [28] Material Effects on the H v d r o l v t i c Reaction The h y d r o l y t i c p r o p e r t i e s of PET are s t r o n g l y d e p e n d e n t on the c h e m i c a l and p h y s i c a l s t r u c t u r e of the specific product From a c h e m i c a l aspect, c a r b o x y l end groups (CEG) and e s t e r groups in the p o l y m e r are the most important factors F r o m a p h y s i c a l aspect, the m o l e c u l a r weight, crystallinity, orientation, and d i a m e t e r of fibers are the m a j o r factors Each of these factors will be d i s c u s s e d below: (a~ C a r b o x y l end g r o u p (CEG} c o n c @ n t r a t i o n C a r b o x y l e n d groups are d e f i n e d as the COOH groups s i t u a t e d at the e n d of the m o l e c u l a r chains Not e v e r y p o l y m e r chain c o n t a i n s a c a r b o x y l e n d group This is d e p e n d e n t on the p o l y m e r i z a t i o n process The c o n c e n t r a t i o n of CEG c o u l d v a r y from I0 to 40 m e q / k g In n e u t r a l w a t e r (pH = 7), R a v e n s and W a r d [29] found that carboxyl g r o u p s c a t a l y z e the h y d r o l y s i s of PET T h e y p r o p o s e d that the rate of h y d r o l y s i s is p r o p o r t i o n a l to the square root of the CEG concentration (b) M o l e c u l a r weight M o l e c u l a r weight Can d i r e c t l y affect the C E G c o n c e n t r a t i o n u n d e r the same p o l y m e r i z a t i o n conditions A polymer with a h i g h e r m o l e c u l a r weight w o u l d c o n t a i n less C E G than a lower m o l e c u l a r weight polymer Sprague [30] o b s e r v e d that a PET g e o t e x t i l e with a lower m o l e c u l a r weight d e g r a d e s faster than one with a h i g h e r m o l e c u l a r weight in a c a l c i u m h y d r o x i d e solution at 50~ Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized HSUAN ET AL ON GEOSYNTHETIC REINFORCING MATERIALS 237 (G) C r y s t a l l i n i t v The rate of h y d r o l y t i c r e a c t i o n is b a s e d on the d i f f u s i o n of water into the p o l y m e r [31] In a PET m a t e r i a l , d i f f u s i o n is g o v e r n e d by the amount of a m o r p h o u s phase m a t e r i a l (d) o r i e n t a t i o n O r i e n t a t i o n of the p r o d u c t has a s i g n i f i c a n t e f f e c t on the d i f f u s i o n rate as d e s c r i b e d in the p o l y o l e f i n s section O r i e n t a t i o n reduces the d i f f u s i o n rate of the p e n e t r a n t M c M a h o n et al [32] f o u n d that the rate of h y d r o l y s i s of PET fibers is d e c i d e d l y s l o w e r than that of films or sheets due to the h i g h l y u n i a x i a l o r i e n t a t i o n of the fiber (e) D i a m e t e r of the fiber In an a l k a l i e e n v i r o n m e n t the h y d r o l y t i c r e a c t i o n is a t o p o c h e m i c a l r e a c t i o n (i.e., r e a c t i o n takes p l a c e on the s u r f a c e of the fibers) [33, 34] If the o v e r a l l p r o p e r t i e s are the same, fibers with a larger d i a m e t e r w o u l d d e g r a d e m o r e slowly t h a n those w i t h a s m a l l e r diameter External Effects on the H v d r o l v t i c Reaction The s u r r o u n d i n g e n v i r o n m e n t has a s i g n i f i c a n t impact on the h y d r o l y t i c m e c h a n i s m s of PET g e o s y n t h e t i c s Two d i f f e r e n t p h e n o m e n a can occur in PET d e p e n d e n t on the e x p o s u r e c o n d i t i o n s In n e u t r a l water (i.e pH = 7) and acidic c o n d i t i o n s (pH < 7), the h y d r o l y t i c reaction is an " i n t e r n a l " hydrolysis The r e a c t i o n is m a i n l y g o v e r n e d by the d i f f u s i o n of water and H + ions into the a m o r p h o u s phase In contrast, " e x t e r n a l " h y d r o l y s i s occurs under a l k a l i n e c o n d i t i o n s (pH > 7) with the p r e s e n c e of c a l c i u m ions Here the rate of r e a c t i o n is s t r o n g l y d e p e n d e n t on the surface area of the m a t e r i a l The f o l l o w i n g d i s c u s s i o n d e s c r i b e s factors which have s i g n i f i c a n t i n f l u e n c e on h y d r o l y s i s : ta) T e m P e r a t u r e The rate of h y d r o l y t i c r e a c t i o n i n c r e a s e s with temperature This is why m o s t l a b o r a t o r y s t u d i e s u t i l i z e h i g h t e m p e r a t u r e s to a c c e l e r a t e the reaction However, c a u t i o n m u s t be applied Since at pH ~ 7, the r e a c t i o n is d i f f u s i o n controlled, the rate of d i f f u s i o n w o u l d l i k e l y vary above a n d b e l o w the glass t r a n s i t i o n t e m p e r a t u r e (whieh is a r o u n d 70~ However, M c M a h o n et al [32] did not o b s e r v e a n y e r r a t i c c h a n g e s in the r e a c t i o n rate w i t h i n the 60~ to 100~ t e m p e r a t u r e range u s i n g u n o r i e n t e d sheet samples (b) DH level The h y d r o l y t i c r e a c t i o n is a c c e l e r a t e d s u b s t a n t i a l l y by a l k a l i n e e n v i r o n m e n t s [35, ~] The h y d r o l y t i c p r o c e s s involves e s t e r groups (R COO R') in the PET chain b e i n g a t t a c k e d by the hydroxide group (OH-), as e x p r e s s e d by E q u a t i o n ii This e s s e n t i a l l y irreversible, since the stable c a r b o x y l a t e u n l i k e l y to react with an a l c o h o l to r e f o r m ester O R ~, OR ~ * OH" ~ R ~ CR' OH reaction anion (RCOO-) is is O ~ R ~" * R'OH (ll) O Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 238 GEOSYNTHETIC SOIL REINFORCEMENT TESTING PROCEDURES (c% C a t i o n e f f e c t s in a l k a l i n e m e d i a An a l k a l i n e solution, pH = 12, can be o b t a i n e d u s i n g v a r i o u s h y d r o x i d e c o m p o u n d s with d i f f e r e n t cations, such as NaOH, KOH, Ca(OH)2, or Mg(OH) Their effects on h y d r o l y s i s vary Halse et al [33, found that Ca 2+ ions have a g r e a t e r e f f e c t 36] and S p r a g u e for I m D r o v i n a Hvdrolvsis Resistance [30] on the rate of the h y d r o l y t i c r e a c t i o n t h a n Na + ions at the same pH level a n d t e m p e r a t u r e s the reason for such v a r i a t i o n is not clear Factors say However, in PET U n l i k e polyolefins, t h e r e are no s p e c i f i c a d d i t i v e s to retard h y d r o l y s i s in PET materials The r e s i s t a n c e s to h y d r o l y s i s must come f r o m the p o l y m e r itself As d e s c r i b e d p r e v i o u s l y , there are five m a t e r i a l f a c t o r s w h i c h relate to the h y d r o l y t i c p e r f o r m a n c e of PET: c a r b o x y l e n d groups, m o l e c u l a r weight, crystallinity, orientation, and fiber diameter P r o p e r m a n i p u l a t i o n a n d c o n t r o l of these factors improves the h y d r o l y s i s r e s i s t a n c e of the polymer ~uqaested Methods of E v a l u a t l n a Hvdrolvsis The h y d r o l y s i s reaction of PET p o l y m e r s is most s e n s i t i v e to high pH solutions a n d high t e m p e r a t u r e s Thus for a c c e l e r a t e d l a b o r a t o r y testing, samples p l a c e d in constant t e m p e r a t u r e baths c o n t a i n i n g v a r i o u s s o l u t i o n s s h o u l d be utilized The E u r o p e a n S t a n d a r d C E N / W G / N [37] has e s t a b l i s h e d two d i f f e r e n t p r o c e d u r e s for e v a l u a t i n g b o t h " i n t e r n a l " and ~ e x t e r n a l " hydrolysis The " i n t e r n a l " h y d r o l y s i s test is p e r f o r m e d at 135~ s a t u r a t e d s t e a m conditions, a n d the ~ e x t e r n a l " h y d r o l y s i s test is p e r f o r m e d at 65~ and pH = II c o n t a i n i n g c a l c i u m ions In addition, the long t e r m p e r f o r m a n c e e v a l u a t i o n u s i n g a m i n i m u m of t h r e e d i f f e r e n t test t e m p e r a t u r e s s h o u l d be c a r r i e d out so that p r o p e r t i e s can be p r e d i c t e d t h r o u g h data e x t r a p o l a t e d methods, such as A r r h e n i u s M o d e l i n g [22] The i n c u b a t e d samples are taken out for t e s t i n g at p r e s c r i b e d i n c u b a t i o n intervals However, if samples are r e t r i e v e d f r o m the f i e l d in order to assess the degree of h y d r o l y s i s of a PET g e o s y n t h e t i c , such test samples s h o u l d be used directly In e i t h e r case (laboratory or field), the f o l l o w i n g test m e t h o d s are r e c o m m e n d e d to be p e r f o r m e d for e v a l u a t i n g the i n i t i a l stages of degradation (Note that a wide range of m o r e c o n v e n t i o n a l p h y s i c a l / m e c h a n i c a l tests can be u s e d to e v a l u a t e a d v a n c e d stages of degradation) la) S o l u t i o n v i s c o s i t y This is a t e c h n i q u e u s e d to m e a s u r e the v i s c o s i t y m o l e c u l a r weight of the m a t e r i a l which is one p a r t i c u l a r value on the m o l e c u l a r weight d i s t r i b u t i o n curve This value d e c r e a s e s as chain s c i s s i o n increases The test p r o c e d u r e to be f o l l o w e d is A S T M D 4603 [38] Certainly, one can use GPC to a n a l y z e the e n t i r e m o l e c u l a r w e i g h t d i s t r i b u t i o n curve, but GPC is m o r e d i f f i c u l t to p e r f o r m and m o r e costly The only r e q u i r e m e n t of the test sample is that it must be s o l u b l e in a solvent at a m o d e r a t e t e m p e r a t u r e (not h i g h e r t h a n 30~ Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized and external tertiary carbons (branch density in PE) crystallinity orientation molecular weight (MW) CEG concentration m o l e c u l a r weight crystallinity orientation fiber diameter polyolefins (oxidation) polyester (hydrolysis) temperature alkaline level cation effect temperature transition metals applied stress annealing External factors dearadation solution v i s c o s i t y (MW) titration (CEG concentration) m i c r o s c r o p y (morphology & fiber diameter) OIT (conventional and high pressure) FTIR (carbonyl group) GPC (MW) Test methods (properties) nolvmer Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized * Note, as degradation proceeds a number of physical and mechanical test methods will e v e n t u a l l y indicate the polymer's change in properties, e.g., strength, elongation, modulus, creep, stress relaxation, impact resistance, etc (MW) Material factors affectina test methods* factors and recor~nended analvtic of internal Polymer (reaction) Table Summary tO > O9 _m m Z _o m m O O9 Z I m rrl -4 > F O Z Z -r O9 c > 240 GEOSYNTHETIC SOIL REINFORCEMENT TESTING PROCEDURES (b~ T i t r a t i o n This m e t h o d is u s e d to m e a s u r e the c o n c e n t r a t i o n of the c a r b o x y l end groups which are acidic and can be n e u t r a l i z e d by an alkaline solution The detail of the test will not be p r e s e n t e d here due to space limitation, but is d e s c r i b e d in Reference [39] The amount of C E G increases with i n c r e a s i n g chain scission (c) O u a n t i t a t i v e m i c r o s c o p y The "external" h y d r o l y s i s on the PET fibrous m a t e r i a l i3 a t o p o c h e m i c a l reaction The surface m o r p h o l o g y can be u s e d to evaluate this phenomena In addition, for PET geotextiles or geogrids, the reduction in fiber d i a m e t e r can be m e a s u r e d as the reaction process progresses SUMMARY This p a p e r presents an o v e r v i e w of the m e c h a n i s m s of o x i d a t i o n and h y d r o l y s i s for p o l y o l e f i n s and polyester, respectively These two p o l y m e r types are w i d e l y u s e d in the m a n u f a c t u r e of g e o t e x t i l e s and g e o g r i d s for reinforcing applications The p o l y m e r also indicates how such m e c h a n i s m s are a f f e c t e d by the m a t e r i a l (internal) p r o p e r t i e s and external environments These internal a n d external factors are s u m m a r i z e d in Table t o g e t h e r with s u g g e s t e d m e t h o d s for e v a l u a t i n g the effects of these d i f f e r e n t long t e r m d e g r a d a t i o n phenomena ACKNOWLEDGEMENT S The f u n d i n g for t h i s s t u d y was p r o v i d e d by the R e s e a r c h I n s t i t u t e ' s C o n s o r t i u m of M e m b e r O r g a n i z a t i o n s a p p r e c i a t i o n is extended G., P o l y m e r D e g r a d a t i o n U n i v e r s i t y Press, 1985 Geosynthetic Our s i n c e r e [i] Grassie, N and Scott, Published by Cambridge and Stabilization, [2] Phillips, D.C., "Effects of R a d i a t i o n on P o l y m e r s , " Science and Technology, Vol.4, 1988, PP 85-91 [3] Albertsson, A.C a n d Banhidi, Z.G., "Microbial Effects in D e g r a d a t i o n of P o l y e t h e n e , " Journal Science, Vol.25, 1980, PP 1655-1671 [4] Rapoport, N.Ya a n d Zaikov, G.E., "Kinetics a n d M e c h a n i s m O x i d a t i o n of S t r e s s e d Polymer," D e v e l o p m e n t s in P o l y m e r D e g r a d a t i o n - 6, 1986, pp 207-258 [~] Morrison, Published [6] Hansen, R.H., Russell, C.A., D.E Benedictis, T., Martin, W.M., and Pascale, J.V., "Inhibition of the C o p p e r - C a t a l y z e d O x i d a t i o n of P o l y p r o p y l e n e , " Journal of P o l y m e r Science: Part A, Vol.2, 1964, PP 587-609 Materials and Oxidative of A p p l i e d P o l y m e r R.T and Boyd, R.N., Oruanic Chemistry, by Allyn and Bacon, Inc, Boston, 1974 of the 3rd Ed., Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized HSUAN ET AL ON GEOSYNTHETIC REINFORCING MATERIALS 241 [7] Michaels, A.S., and Bixler, H.J., "Solubility of Gases in Polyethylene," Journal of Polymer Science, 50, 1961, PP 393-412 [8] Rapoport N.Ya., Berulava, S.I., Kovarskii, A.L., Musayelyan, I.N., Yershov, Yu.A., and Miller, V.B., ~The Kinetics of Thermooxidative Degradation of Oriented Polypropylene in Relation to the Structure and Molecular Mobility of the Polymer," Vysokomol Soyed, AI7:II, 1975, PP 2521-2527 (Translated in Polymer Sci U.S.S.R., 17:11, 1975, PP 2901-2909) [93 Holmstro~m, A., ~The Course of Thermoxidative Degradation of LDand HD-Polyethylene Under Accelerated Testing Conditions," Durabilitv of Macromolecular Materials, Edited by Eby, R.K., ACS Symposium Series 95, ASC Washington, D.C., 1979, pp.45-62 [lOJ Chan, M~ and Allara, D.L., "Infrared Reflection Study of the Mechanism of Oxidation at a Copper-Polyethylene Interface," Journal of Colloid and Interface Science, Voi.47, No.3, June 1974, pp 697-704 [11] Osawa, Z., and Ishizuka, T., "Catalytic Action of Metal Salts in Autoxidation and Polymerization X The Effect of Various Methal Stearates on the Thermal Oxidation of 2,6,10, 14-Tetramethylpentadecane, " J of Applied Polymer Science, Vol 17, 1973, pp 2897-2907 [/2.] Reich, L., Jadrnicek, B.R., and Stivala, S.S., "Effect of Oxidation-Reduction Potential on the Metal Salt-catalyzed Autoxidation of Atactic Polypropylene," J Polymer Sci., A-l, 1971, pp 231-233 9, [.,L3.] Peterlin, A., "Molecular Mechanism of Plastic Deformation of Polyethylene," The Meaning of Crvstallinitv in Polyr~ers, Ed by Price, F.P., J of Polymer Science, Part C, Polymer Symposia, No.8, 1966, pp 123-132 [14] Wisse, J.D.M., "The Role of Thermo-oxidative Ageing in the LongTerm Behaviour of Geotextiles," Durability of Geotextiles, Rilem, 1988, pp.207-216 [.1_5] Halse, Y.H., Lord, A.E Jr., and Koerner, R.M., "Ductile-toBrittle Transition Time in Polyethylene Geomembrane Sheet," Geosvnthetic Testing for Waste Containment Applications, ASTM STP 1081, R.M Koerner, ed., ASTM, Philadelphia, 1990, pp 95-109 [/ 5] Shanahan, M.E.R., "The Role of the Liquid in Environmental Stress Cracking of Polyethylene," Journal of Materials Science Letters, 2, 1983, pp 28-32 [.iT.] Rapoport, N.Ya., Livanova, N.M., and Miller, V.B., "On the Influence of Internal Stress on the Kinetics of Oxidation of Oriented Polypropylene," Vysokomol soyed AI8 : 9, 1976, PP 2045-2049 (Translated in Poly Sci U.S.S.R., 18, 1977, PP 2336-2341.) Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 242 GEOSYNTHETIC SOIL REINFORCEMENT TESTING PROCEDURES [18] Walker, D.M., and Juzkow, M.W., "PE/Carbon-black Survives 20 Years of Weathering in Canada," ~ , May 1983, pp 68-72 [19] Root, S., "Stabilization of Polypropylene Fiber for Textiles and Geotextiles," Ciba-Geigy Corp Internal Report, 1987 [20] Hawkins, W.L., "Recent Advances in Mechanisms for the Stabilization of Polyolefins," J Polymer Sci., Symp No 57, 1976, PP 319-328 [21] Gray, R.L., "Accelerated Testing Methods for Evaluating Polyolefin Stability," Geosynthetic testing for Waste Containment Applications, ASTM STP 1081, R.M Koerner, ed., ASTM, Philadelphia, 1990, pp 57-74 [22] Koerner, R.M., Lord, A.E., Jr., and Hsuan, Y., "Arrhenius Modeling to Predict Geosynthetic Degradation," J Geotextiles and Geomembranes, II, 1992, pp 151-183 [23] Cadwalladar, M.W., "The Relation of High Pressure OIT to Oven Aging for HDPE Liner", 4th Int Conf on Geotextiles, Geomembranes and Related Products, Netherlands, May 1990, p 593 [24] Conley, R.T., Inc., Boston, [25] Thomas, R.W., "An Introduction to IR Spectroscopy for Geosynthetic Applications," Geotechnical Fabrics Report, September 1991, pp 22-24 [26] Halse, Y., Mertz, J., and Rigo, J.M., ~Chemical Identification Methods used to Characterize Geomembranes," Rilem Report 4, Geomembranes : Identification and Performance Testing, Ed by Rollin A.L and Rigo, J.M., Published by Chapman and Hall, London, 1991, pp 316-336 [27] Odian, G., Principles of Polymerization, by Weily-Interscience, New York, 1981 [28] zimmermann, H., "Degradation and Stabilization of Polyesters," Developments in Polvmer DeQradation - 6, Edited by N Grassie, 1986, pp 79-119 [29] Ravens, D.A.S., pg 150 [30] Sprague, C.J., ~Leachate Compatibility of Polyester Needlepunched Nonwoven Geotextiles," Geosvnthetic Testin~ for Waste Containment ApDlicatlons, ASTM STP 1081, R.M Koerner, ed., ASTM, Philadelphia, 1990, pp 212-224 Infrared Spectroscopy, 1966 and Ward, Published by Allyn and Bacon, Second Edition, Published I.M., Trans Faraday Soc., 57, 1961, Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized HSUAN ET AL ON GEOSYNTHETIC REINFORCING MATERIALS 243 [31] Golike, R.C and Lasoski, S.W Jr., ~Kinetics of Hydrolysis of Polyethylene Terephthalate Films," J of Phys Chem., 64, 1960, pp 895-898 [32] McMahon, W., Birdsall, H.A., Johnson, R.G and Camilli, C.T., "Degradation Studies of Polyethylene Terephthalate," J of Chemical and Engineering Data, 1959, pp 57-79 [33] Halse, Y., Koerner, R.M and Lord, A.E., Jr., "Effect of High Levels of Alkalinity on Geotextiles Part : Ca(OH) Solutions," J of Geotextiles and Geomembranes, 5, No 4, 1987, pp 261-282 [34] Namboori, C.G.G and Malcolm, H.S., "Steric Effects in the Basic Hydrolysis of Poly(ethylene Terephthalate)," J of Applied Polymer Sci., Vol.12, 1968, pp 1999-2005 [35] Risseeuw, P and Schmidt, H.M., "Hydrolysis of HT Polyester Yarns in Water at Moderate Temperatures," 4th Int Conf on Geotextiles, Geomembranes and Related Products, Netherlands, May 1990, pp 691-696 [36] Halse, Y., Koerner, R.M., and Lord, A.E., Jr., ~Effect of High Levels of Alkalinity on Geotextiles Part : Na(OH) Solutions," J of Geotextiles and Geomembranes, 6, No 4, 1987, pp 295-306 [37] Proposed European Standard CEN/W5/N37 "Hydrolysis of Polyester" [38] ASTM D 4603 ~Viscosity of Poly(Ethylene Terephthalate Inherent, Determining" [39] Haslam, J., Willis, H.A and Squirrell, D.C.M., Identification and Analvsis of Plastics, Second Edition, Published by Butterworth & Co., Ltd., London, 1972 (PET), Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized STP1190-EB/Aug 1993 Author Index A K Abramento, M., Austin, D N., 90 Koerner, G R., 163 Koerner, R M., 49, 163, 228 Krstic, R., 207 L Ballegeer, J P., 16 Bathurst, R J., 32 Bauer, G E., 138, 195 Berg, R R., 152, 184 Bright, D G., 218 Larson, D G., Lord, A E., Jr., 228 M Montanelli, F., 64 C N Cancelli, A.,64 Cazzuffi, D., 119 Collin, J.G., 152, 184 Crouse, J L., 207 Netravali, A N., 207 P Paulson, J N., 111 Picarelli, L., 119 E Elias, V., 163 R Razaqpur, A G., 195 Ricciuti, A., 119 Richmond, L E., 207 Rimoldi, P., 64, 119 Simac, M R., 32 F Farrag, K A., 76 Fleck, J A., 49 W G White, D F., 90 Whittle, A J., Wilson-Fahmy, R F., 49 Wu, J T H., 16 Wu, K.J., 90 Germaine, J T., Griffin, P., 76 H Z Halim, A O A., 195 Hsuan, Y G., 228 Zhao, Y., 138, 195 245 Copyright9 1993byASTM International www.astm.org Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized STP1190-EB/Aug 1993 Subject Index G A Aggregates, 195 ASTM standards, 152 D 61:16 D 1682:16 D 4595: 32, 111 Automated plane strain reinforcement cell, Geocells, 64 Geogrids damaged, 195 degradation of, 228 installation damage, 163 modular block, 32 pull-out testing, 76, 119, 184, 195 tensile modulus, 90 Geonets, 49 Glass transition temperature, 207 Grain size distribution, 76 Granular soils, 76, 138 Gravel, 119, 163 B Backfill, 163 Bearing capacity, 64 Biocides, 218 C Chemical stability, 207 Clay liners, 49 Cohesive soils, 76 Compaction procedure, 76 Composite material, geogrid, 184 Concrete block units, 32 Confinement, 16, 49 soil, lateral spreading, 64 Creep, 284 H Hydraulic testing, 64 Hydrolysis, 207, 228 I Installation damage, 163, 195 L D Degradation, fiber, 207, 218, 228 Dilatancy, soil, 138 Direct shear test, 119, 138, 152 Displacement, 195 E Extensometer, 90 Limit equilibrium, 152 Liners, clay, 49 Loading, 32, 184 deformation properties, 16 extension modulus, 49 pull-out, 76 transfer evaluation, M F Microorganisms, effect on geosynthetics, 218 Moisture content, soil, 76 Factors-of-safety, 195 partial, 163 247 248 GEOSYNTHETIC SOIL REINFORCEMENT TESTING PROCEDURES N Needle-punched geotextiles, 49 Nonwoven geotextiles, 16 needle-punched geotextiles, 49 O Oxidation, 228 P Planar reinforcement, Plane strain test, Polyester, 111, 195, 207, 228 Polyethylene terephthalate, 228 Polymeric degradation, 207, 218, 228 Polymeric reinforcement, 163 Polyolefins, 228 Polypropylene, 90, 228 Pull-out tests, 76, 119, 184, 195 R Ribs, geosynthetic installation damage, 163 single, 90 Rubber membrane, 16 Sand-steel data, Shear failure, 64 Shear lag analysis, Shear strength, 119, 138, 152 Shear stress strain, 76 Silt, 184 Silty sand, 119 Single end break, 111 Single rib, 90 Slippage, 16 Soll friction angle, 152 Stability, fiber, 228 biological, 218 chemical, 207 Standards (See also ASTM standards) degradation, 218 geocells, 64 Steel sheet inclusion, Stiffness, 16 Strain rate, 184 Stress degradation, 207 Stress strain curves, 16 shear, 76 T Tensile properties D 61:16 D 1682:16 D 4595: 32, 111 modulus, 90 strain, 138 strength, 49 stress, 64 measurement, Triaxial test, 119 W Wide width strip method D 4595: 32, 111 Wide width tension test, 49 Woven geotextiles, 16, 49 polyester, 111 ISBN 0-8031-1885-6 Copyright by ASTM Int'l (all rights reserved); Tue Dec 29 00:50:13 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further repro