ML20195G347
| ML20195G347 | |
| Person / Time | |
|---|---|
| Issue date: | 08/27/1987 |
| From: | Junjling T, Mcdaniel K, Person L NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | |
| Shared Package | |
| ML20151C617 | List:
|
| References | |
| FOIA-88-470 NUDOCS 8811230355 | |
| Download: ML20195G347 (41) | |
Text
i~
o -
l 0 l Status of NRC's Waste Fom f
'legulatory Guide by Thomas L. Jungling, Keith K. McDaniel, LeRoy S. Person and Michael Tokar Division of Low-Level Waste Management and Deconsnissioning Office of Nuclear Material Safety and Safeguards 99,8 rec p s -
% +J.
p e
O h
L) N e
O
% %' p*&
ms
~
Presented at the Ninth Annual DOE Low-Level Radioactive Waste Management Conference Denver, CO August 27, 1987 l
.) i I
g 12 g 5 001115 I RESNIKOBB-470 PDR I i
. e c LLWM PAPER -
- 1.-
l STATUS OF NRC'S WASTE FORM REGULATORY GUIDE ABSTRACT The Nuclear Regulatory Connission's (NRC's) 1983 Technical !
Position on Waste Form is being modified for publication as a Regulatory Guide. The Regulatory Guide necessitates the testing of low-level waste fonns to deranstrate stability. As a result.
vendors have perfonned and supported extensive research and testing, results of which are included in their topical rvorts.
In the course of NRC's review of these topical reports, the NRC has identified some areas that require further evaluation. '
Included among these are 1) cement waste fonn long-term structural stability (2)(bitumen waste form strength and viscosity characteristics, and (3) polyethylene high integrity container (HIC) structural stability. To expedite their resolution, the NRC will encourage vendor participation in addressing these issues. This paper discusses current NRC activities and strategy for dealing with the complex technical issues on waste fonn stability and describes laboratory testing and analyses, performed by Brookhaven National Laboratory, which play a supportive role in resolving these issues.
Discussion *is also included on the schedule for further NRC action in implementing waste form requirements.
INTRODUCTION In December 1982 the NRC promulgated the low-level radioactive waste management regulatic..,10 CFR Part 61 (Ref.1). One year later the waste '
t classification and waste fonn requirements went into effect. To provide waste generators early guidance for complying with these requirements, the hRC
! published in May 1983 the Technical Fositions (TPs) on Waste Classification and Waste Fonn (Refs. 2 & 3). The TPs are currently being modified for publication as Regulatory Guides (RGs).
Compliance with the regulatory requirements and reconnendations would nonnally require detailed inspections at each licensee facility. To expedite l detennination of compliance. NRC has encouraged preparation of a Topical Report (TR)byeachvendorforeachparticularpackagingmethodorsystem. The l
TR approach was adopted to provide a centralized national level of review with active participation by the States.
e
- - -- - = -
LLnM PAPER f
This paper describes the pending update (in the form of a draft Regulatory Guide) to the TP on Waste Form and presents current NRC staff views en technical issues that address stability. The most recent technical issues of interest include (1) spalling, cracking and atypical strength behavior of cement waste forms, (2) viscoelastic behavior of bitumen solidified waste foms, and (3) buckling and creep of polyethylene high integrity containers. ,
BACKGROUND L
Regulatory Requirements i
The basic technical requirements for waste classification and waste characteristics are given in 10 CFR 61.55 and 10 CFR 61.56, respectively. The waste classification system divides low-level wastes acceptable for near-surface disposal into three categories designated as Classes A,B,and C. Class .
A wastes have the lowest concentrations of radionuclides and are required to meet only minimum waste form requirements. Class B wastes have higher concentrations and must also meet stability requirements. Class C wastes have even higher concentrations of radionuclides and besides meeting the requirements i of Class B wastes must be disposed of with protection for an inadvertent '
intruder. The structural stability requirements for Classes B and C wastes currently are achieved by the use of high integrity containers, by '
solidification of the waste, or by taking credit for the inherent stability of !
the waste. '
The minimum requirements for waste characteristics (10 CFR 61.56(a)) are I intended to ensure operator safety durin The stability requirements (10 CFR 61.56(b))gare handling intended of the wastes. subsidence to minimize j
effects in the disposal facility by maintaining gross physical properties .,
l and identity for a minimum of 300 years. Section 61.56(b) clarifies the meaning of stability and identifies disposal conditions which the wastes must withstand: external load, moisture, microbial activity, radiation, and chemical i
attack. With respect to Class C wastes, barriers against inadvertent intrusion should have an effective life of at least 500 years.
Additional Guidance i i
The waste form requirements in 10 CFR Part 61 are relatively general with regard to testing parameters and minimum conditions of acceptance. The NRC t staff refrained from listing prescriptive requirements to allow needed !
! flexibility because of the multitude of different waste forms and types of l waste generators who ship to concercial disposal sites. The 1983 Technical l Position on waste form provides more specific guidance, however, and the ;
i Regulatory Guide that is under development will reflect knowledge gained from testing and analyses performed on waste forms and high integrity containers as part of the TR review process. !
l l
l 1
-.- - - - . - - -- - - - , . , _ - , , -._ _--,-- _- , - , . , . , _ ._,,.__.,,-,_,,._,,,,,w n., . , - - - . , . - -
LLWM PAPER TECHNICAL POSITION The waste form TP elaborates on the provisions of 10 r.FR 61.56. Class A wastes, having luw concentrations of nuclides do not have to be stabilized, but on disposal must be segregated from Classes B and C wastes. If Class A wastes are solidified and segregated from Class 8 and Class C wastes, they need only be free-standing monoliths having a free liquid content not more than 0.5% by volume.
If not segregated, such wastes must meet the structural stabdity requirements of Classes B and C wastes.
- Classes B and C wastes are intended to maintain their gross physical properties and physical identity over a 300-year period. The TP provides guidance that allows ~ demonstration of the required structural stability by subjecting samples of the waste foms to a series of accelerated tests. The reconnended tests include initial compressive strength, leach resistance to
- appropriate aqueous media, compressive strength after innersion in water, resistance stability.
to biological attack, radiation resistance and thermal cycling The reconnended tests were chosen to provide a conservative estimation of the potential long-term stability of the waste form. The tests were not intended, in all cases, to duplicate actual burial conditions but rather were intended to subject the product in a short time period to conservative conditions that could degrade the structural integrity of the waste fom.
Following these tests, material property measurements are made to determine whether significant degradation has occurred. -
TP Tests for Solidified Waste forms The minimum reconnended compressive strength is based on the mechanical load a waste form would experience within a disposal trench and is not necessarily indicative of a waste form's long-term stability. The recomended leach test provides a measure of the rate of release of radionuclides from a waste fons when exposed to water. The leach resistance is calculated using the method described in ANSI /ANS 16.1, which models radionuclide release by diffusion. The reconnended minimum leachability irdex of 6 corresponds to the maximum release of radionuclides which, when inputted into a pathways analysis, will satisfy the off-site expasure requirements. The 90-day innersion test can be performed in conjunction with the leaching test and is important in helping to assure that the waste fonn will not lose its gross physical dimensions when exposed to wet environments for long periods of time.
The blodegradation tests are short-tenn qualitative tests that provide an indication of whether the waste form will biologically degrade. The results do not indicate the extent of degradation. If microbial activity is observed, additional quantitative testing may need to be performed to confirm that the i
i 1
,,. - _ _ . , , - - -- ----------w.
, LLWM PAPER waste form will not significantly degrade over the long-term. To test for radiation resistance of the waste form, an accumulated radiation dose of 10E8 rads is administered based on NRC experience of the upper dose limit of what is expected from routinely generated wastes. The thermal degradation test is relevant to assess potential waste form degradation resulting from possible exposure of the waste to extreme temperatures during transportation and storage prior to disposal. The intent of the free liquid limit is to minimize trace quantities of liquids which might result free condensation during bandling, storage, and transport.
The above accelerated testing may be performed on simulated, non-radioactive wastes. If laboratory size specimens are used, these samples should be correlated with full-scale waste fonns to demonstrate that the actual waste products will have similar properties as the specimens tested.
High Integrity Containers e
Stability can also be achieved through use of HICs. These should also have a minimum life-time of 300 years. Tests to which HICs must be subjected include consideration of their mechanical strength, the impact of thermal '
loads, chemical and biological interactions with both the disposal environment and the contained waste, gama and ultraviolet radiation, and the ability to l withstand various handling test. The HICs should also be able to meet the Department of Transportation's Type A package qualifications.
An important aspect in the design and use of HICs is a quality assurance (QA) program. The QA program should give special consideration to fabrication, testing and use of,the containers. For certain containers, specific wastes may need to be restricted frodi contact with the containers. The QA program should fully address this area. Finally, a Process Control Plan should be developed to ensure that the one percent, free-liquid reoufrement and any potential
! restrictions on waste stream compatibility will be ret.
REGULATORY Gul0E Since the issuance of the TP on Waste Form in May 1983, it has been recognized that additional guidance or modifications to the existing guidance were necessary. These needs are being considered in preparation of the
, Regulatory Guide on Waste Form Stability. This Guide will provide guidance to both fuel-cycle and non-fuel-cycle waste generators on acceptable waste form l
l test methods and on what constitutes acceptable test results for demonstrating j compitance with 10 CFR Part 61. The purpose is to provide recomended methods for demonstrating compliance with the 300-year stability requirement for Class B and Class C wastes.
l l
l
, LLWM PAPER General Changes for Solidified Wastes Several of the recommendations in the TP have been clarified. A sunfary of the recommended tests is included in Table 1. One item is the definition of major waste streams needing qualification. Certain wastes reoutring qualification are specifically named and include bead resins, powdered resins, boric acid and sodium sulfate evaporator bottoms, and individual decontamination solutions. Minor, infrequent variations in the waste stream composition (approximately three percent outside the nominal weight percent) are expected control and should be addressed in the oetailed plant. specific process programs. Therefore, complete testing of minor variations in waste streams is not intended.
The compressive strength requirement for solidified waste forms has been increased from 50 to 60 psi to reflect the change in burial depth at the Hanford disposal site from 45 to 55 feet of soil overburden. '
Table 1 Solidified Product Guidance Test Method Resul
.....................................................................t
~
- 2. Radiation stability 0.4 MPa after 10E8 Rads i 3. Biodegradation ASTM G21 and G22 No Growth
- 4. Leachability ANS 16.1 LIX of 6
- 5. Innersion 0.4 MPa after 90 days r l l
- 6. Thermal cycling ASTM B553 0.4 MPa after 30 cycles
(
l from .40C to 60C
! 7. Free liquid ANS 55.1 0.5 percent
\
t
' 8. Full. scale tests Homogeneous and l
l correlates to lab size test results
LLWM PAPER Specific Changes for Solidified Wastes Bitumen-The original TP for waste form stability tests reconinended that bituminized waste forms be tested in accordance with ASTM 0-1074, "Compressive Strength of Bituminous Mixtures", (Ref.4) ar:d that test specimens should show a compressive strength of at least 50 psi. The mechanical load expected during burial has now risen to 60 psi due to the deeper burial depths being instituted at one operating site. For this compression test it was anticipated that the-test specimens would exhibit shear failure. However, waste forms such as bitumen, may undergo long-term creep when subjected to burial site loads, as would be typical of materials which exhibit viscoelastic behavior. In addition, these materials are not in a rigid monolithic form during burial; they could have a tendency to flow. Therefore, it should.be demonstrated that the initial compressive strength of bituminized waste forms is adequate to resist the maximum burial loaos that would be imposed consistent with the '
placement of backfill material around the waste foms. This means that these waste forms should maintain their gross physical dimensions after undergoing the accelerated testing perfonned to demonstrate these waste forms long-term stability.
There are two ways to demonstrate that bituminous waste forms have adequate compressive strength. One acceptable method is by using standard untaxial compression tests that show that the waste forms have a minimum compressive strength of 60 psi. The second method is to use triaxial compressive strength tests to measure the shear strength of the bituminized waste sample. In t.rtaxial compression tests a confining pressure is applied to the specimen normal to the vertical compressive load. This t reconsnended (as an alternative to uniaxial compression tests)ype of test isthe to simulate confining pressures which would exist in a backfilled waste disposal environment. The maximum confining pressures to be used should be less than or equal to the pressare produced by five meters of trench cover naterial. The triaxial compressions test is more complicated and costly than the untaxial compression tests, but it may be the preferred method to demonstrate that the j
bituminized waste can withstand the anticipated burial loads, taking into consideration the effects of the backfill. The draft Regulatory Guide is being revised to permit these alternative methods of compressive strength testing to be selected at the option of the vendor.
Cement-Solidified Waste As a result of concern regarding how the strength of cement solidified waste forms varies with cure time, the NRC contracted with Brookhaven National Laboratory (BNL) to analyze this phenomenon using formulations from cement
i LLWM PAPER vendors. BNL test results indicate that curing conditions (as well as other parameters) appear to have an effect on waste form strength and the resistance of the waste form to cracking and spalling upon contact with water.
Specifically, the test specimens subjected to 90 day immersion tests gererally did not show an increase in compressive strength with cure time that is prototypic of portland cement specimens. Most specimens tested also show varying degrees of surface degradation, including cracking and spalling.
Specimens also exhibited decreasing strengths during the immersion period which suggests that the waste forms might lose their integrity well before the end of the 300 year period required by 10 CFR Part 61, even tilough their initial strengths were greater than 60 psi. To ensure a reasonable degree of long-term confidence in cement-based solidifications, the product should exhibit typical cement behavior in so far as demonstrating increased strength with time while showing minisul surface degradation.
BNL test results indicate that in addition to the length of cure time, thW' amount of resin loading may also have an effect on the waste form's strength characteristics. This appears evident in Figure 1, which plots the percent change in compressive strength (in going from a 7-day cure time to a 14-day or 28-day cure time) after 90 days of immersion verses the percent, by weight, of dewatered resin loadings. Resins used were 50% anion and 50% cation by weight.
The cation resins were all 40% expended of their capacity. The 26%, 28%
and 38% resin loadings represent three different vendor formulations, while the 12% loading represents a reference formulation. The two lines represent batches cured for one week and three weeks. Although other variables not
' represented in this figure contribute to the waste forms strength characteristics (such as additives .used) And although there exist a limited number uf data points, it can be seen that as resin loadings increase, the strength after 90 days of immersion tends to decrease.
As a result of these and other similar test results the draft Regulatory Guide on Waste Form Stability is being revised to include two new provisions:
(1) that the waste form exhibit no significant surface or bulk degradation effects (e.g., cracking, spalling, or disintegration) following the water l immersion tests; (2) that the waste forms exhibit typical Portland cement strength behavice (i.e., increasing strength with cure time). Vendors will be l
expected to provide data with their topical report subnittals that show that
(
their cement solidification agents will satisfy these criteria.
i i
l l
l l
I _ _ .
LLWM PAPER i
FICilllR E 1 100 M Change in Strength vs. 7. Loading 90 -
80 -
70 -
60 -
50 -
S 40 -
E 30 -
j 20 -
vi to.
Ji o
& ~ 10 -
- E -2 0 -
-30 -
M -40 -
-50 -
-60 -
-70 -
-8 0 -
-9 0 -
-100 , , , , , , , , , , , , , , ,
10 14 18 22 26 30 34 38
% Loading a 4-wk vs 1-wk cure + 2-wk vs 1 -wk cure l
General Chan,gst for HICs Several recommendations regarding HICS have been modified. The current recommendations are summarized in Table 2 below, i Several incidents of internal pressurization of HICs resulting from i unrelated causes, such as biological activity, chemical contamination, and long storage times, have been observed. As a result, the H!C design is now required to include passive vents to prevent internal pressurization while minimizing water inflitration. The material used in the vent should also be subjected to other HIC material tests. '
The references for the Type A package testing have been modified to reflect subsequent changes in the NRC and the Department of Transportation 9
, LLWM PAPER
, 9-I regulations. In addition, the 25. foot 6 rop , cst required by the States of South Carolina and Washington has been incorporated into the RG.
- With respect to mechanical strength, the HIC design should be conservative and should include a safety factor of approximately 2.0. In determining the effect of chemicals on the performance of the HIC, the full life of the HIC should be considered. At the end of 300 years, the HIC should still meet the stability requirement despite degradation through corrosion or other chemical attack by the contained waste or by the environment.
Table 2 Hich. integrity Container Design Guidance
- 1. Design for 300 year lifetime objective 1
- 2. Design to withstand corrosive and chemical environment
- 3. Design to withstand loads of burial *
- 4. Materials designed to withstand 10E8 Rads
- 5. Materials resistant to biodegradatio'n
- 6. Design to DOT Type A package qualification
- 7. Conduct prototype testing
- 8. Have quality assurance program
- 9. Use process control program to demonstrate Specific Changes for HICs As a result of concern regarding the long term stability of high density polyethylene (HDPE),HICs, the NRC contracted with BNL to analyze existing data on the creep of polyethylene and develop a computer model to evaluate the structural stability of these HICs. In addition, the 8NL model included analysis to determine the HICs potential to buckle when subjected to burial loads. Buckling, the sudden deflection associated with an unstable equilibrium condition which can result in either partial or total collapse of the structure, is by its very definition a condition of instability, and thus incompatible with the concept of structural stability. Therefore, the draf t Regulatory Guide will contain a recommendation that the HDPE HICs be shown not to buckle.
A draft methodology report describing the development of the BNL code has recently been provided to HDPE H!C vendors and the concerned State authorttles (Ref5). The code, which only became operational at the NRC in July, indicates that large HOPE HICs may ex *eed the allowable buckling and creep stresses and allowable membrane stresses when subjected to 25 foot burial loadings. Some small HDPE Hic designs can satisfy the buckling criteria contained in the code, however.
4 i
9
, LLWM PAPER
, 10 e '
The HDPE HIC vendors and concerned States are being notified of the i
BNL/NRC their HICSfindings and the vendors will be requested to reevaluate or redesign accordingly.
Changes to the RG concerning HOPE HICs, will te trade to include the recommendation that in addition to buckling 45 defined by BNL, (Ref.5) the design and proposed use of the HICs should preclude the enset of tertiary creep and/or the violation of allowable membrane stresses. i l
SUMMARY
The Draft Regulatory Guide on Waste Form Stability reflects several revisions from the 1983 Technical Position on Waste Form. The most recent and perhaps most significant revisions concern cement and bitumen waste forms and l polyethylene high integrity containers. These revisions can be befefly -
sumarized. To demonstrate compressive strength stability for bitumen waste foms, a minimum strength, as demonstrated by a triaxial or uniasial !
4 compressive strength test, and administrative backfill are recomended. r To provide assurance that cement waste. forms will not degrade with time, typical Portland cement-like strength behavior and lack of significant surface or bulk degradation following imersion testing should be demonstrated. High ,
density polyethylene high integrity containers should be designed to preclude buckling as well as creep failure. The draft Regulatory Guide will be released ;
for public coment pending the incorporation of these revisions.
l
. l i
REFERENCES :
- 1. Title 10. Code of Federal Regulations, Part 61, Revised as of January 1, 1986. l l
- 2. Technical Position of Radioactive Waste Classification, Rev. O, t
May 1983, U.S. Nuclear Regulatory Comission. !
)
- 3. Technical Position on Waste Form, Rev. O. May 1983, U.S. Nuclear
! Regulatory Comission, !
- j 4
ASTM 0-1074 "Compressive Strength of Bituminous Mixtures". American !
j Society of Testing and Materials. !
i i i 5. J. Pires, "Review of the High Integrity Cask Structural Evaluation f i l Program (HICSEP)", BNL-FIN A-3171/15, Oraf t Report, April 1987, t I
r l
l ;
I !
l i
NL k 9l6fer PROGRRH REVIEW FOR FIN R-3291 PROGRRH DN LLW PREKRGE RND ENGINEERED BRRRIER STUDY '
l P.500 L.MILIRN E.I.RNDERSON i
SEPTEMBER 1987 l
a i
NUELERR WRSTE RND HRTERIRLS TECHNOLOGY DIVISION BROOKHRVEN NRTIONRL LRBORRTORY DEPRRTHENT OF NUELERP. ENERGY l UPTON, NEW YORK 11973 6
LLW PREKRGE/ ENGINEERED BRRRIER STUDY !
TR5K 1 -
WORK PLRN ,
TR5K 2 -
STRBILITY OF EEMENT-BRSED BARRIERS TR5K 3 -
DEGRADRTION MEEHANISM5 IN !
HIGH DENSITY POLYETHYLENE CHDPE)
TRSK 4 -
BIODEGRADRTION OF IX MEDIR j i i
TR5K 5 -
HDPE TESTING PROTOCOL i
l r
- FY 85 FY 87 FY 88 l
TR5K1 '
TRSK 2 '
I l
! l I
j TR5K 3 l
I TR5K 4 I TR5K 5 l
I' 4
TR5K 2 - STRBILITY OF EEMENT-BRSED BRRRIERS INITIRL EHDICES OF MRTERIRL5 WERE
- 1. PORTLRND I EEMENT MORTRR CEONTROL)
~
- 2. PORTLRND V C50 RESISTANT)
- 3. ONTRRIO HYDRO EEMENT MORTRR WITH SILIER FUME + 5UPERPLRSTIZER jf EHICHIBU HIC MRTERIRL J. WESTINGHOUSE SUREPRK l
LRST 2 EHOIEE5 DROPPED BEERU5E OF DIFFIEULTIES IN OBTRINING SRMPLES.
1
g g b d <o gj 1 TYPE 5 0F DEGRRDRTION TESTS TWO TEST 5 REEDHMENDED BR5ED ON LITERRTURE SURVEY.
l
- 1. SULPHRTE RTTPCK
! 2. GRHHR-IRRRDIRTION UP TO 18 RRD l
l l
SULFRTE RTTREK TEST 5 DESIGNED TO EDHPRRE BEHRVIOR OF VENDOR BARRIER HRTERIRL5 USING ESTABLISHED TESTS RSTH-E1012: CONTINUOUS IMMERSION IN Na250 4 50LUTION OR Na2 504 /Mg50 4 MIXTURE
-TEST DURRTION MRY LR5T UP TO 1 Y BURERU OF REELRHRTION TEST:
REEELERRTED TEST INVOLVING RLTERNRTE IMMERSION IN 2.1x Na2504 G5 HOURS) RND DRYING C8 HOURS RT ST D FRILURE IS DEEMED TO DEEUR IF SRMPLE EXPRND510.5X IN LENGTi Cd m.<,
unik ,A,,
- 4.
f
TEST HRTRIX FDR EEMENT-HORTRR SRHPLES SRHPLES HER5URE 10" x 1" x 1" I
IMMERSION TIME IMMERSION SOLUTION 4
CHo.) Na2 509 DIN 3 3X 3 5 3 3 12 3 3
- Number of replicate specimens.
A c,#
L.-i) gh N' 0 $g 4 $ g '
EURRENT STRTUS OF 50*[ RTTREK TEST 5
- 1. INITIRL EXPERIMENTS COMPLETED TO DPTIMIZE PREPRRRTI0h DF SRMPLES AND MOLDING PROCEDURE 5 1
- 2. RLL 5RMPLES ER5T RND RRE BEING EURED
l l l GRHHR-IRRADIRTION TESTS l i
0 TESTS WERE DEVISED TD [0NFIRH i S >ff THRT 108 RRD IRRRDIRTION IS NOT DELETERIOUSTO TO RT LE I STRENGTH OF EEMENT-BRSED BRRRIERS.
j .
j i 0 TESTS INVOLVE POST-IRRRDIRTION !
j EXRHINRTION FOR VISURL EHRNGES j FOLLOWED BY EDHHPRE55 ION TESTING. -
1 l
l
TEST HRTRIX FOR EEMENT-MDRTRR IRRRDIRTION STUDIE5 o TEST SPEEIHENS RRE 1" EUBES IRRRDIRTED IN RIR RT 10 E. j l
Number of Samples Tested Irradiated Dose Rate ,
Irradiation Time. !
CHonths.) 5x18 3 rad /hr 1 ad/hr Non-Irradiated !
3 2a 2 3 5 2 2 3 12 2 2 3 aRepresents the number of replicate samples prepared for each of the 3 binder types considered CPI and PV cement mortars and Ontario Hydro cement mortarl
-1 o STRTUS l
EUBES EURRENTLY BEING EURED. l r
i l
1 TR5K 3 - DEGRADRTION MEEHANISMS IN HDPE SCOPE: TO IDENTIFY DEGRRDRTION MODE 5 FOR
! VRRIOUS EHEMIERL RND IRRRDIRTION l ENVIRONMENTS
. THESE INCLUDE: !
i o RIR o DIW
! o IGEPRL EO-530
! CASTM TEST SURFRETRNT) !
j o TURBINE DIL l
! CP053. LLW EONTRMINRNT) l l o SEINTILLRTION FLUID !
- CP055. LLW EONTRFI4RNT)
- o ERMMR RRDIRTION ,
l Q ..) p# * ;st .
l t 4
TYPE 5 0F MECHRNIERL TEST 5 ON HDPE
- 1. STRTIE U-BEND
- SIMPLE, INEXPENSIVE, VER5RTILE 5[0 PING TEST
- 2. DYbRMIC CREEP-RUPTURE
- DURNTITRTIVELY COMPRRES
[REEP RRTES, FRILURE TIMES, DUCTILITIES FOR DIFFERENT ENVIRONMENT 5
- [
U-BEND TESTS ON HDPE .
l I
NEW SIMPLE TEST TO CHEEK CRREK INIRTION RND PROPRGRTION HEEHANI5H5 IN STRESSED HDPE !
i I TEST ENVIRONMENTS INCLUDE:
l o GRMMR IRRRDIRTION !
l o RIR ,
1 o DIN -> A a.:Ei% h.
l o Na * " " -
f l
l l
i
- ~
v,
,r .. . k c
% cn l
l' .
. Q p' *,;'.j . . ; - O =t.0
~
a.
e
'."p,-. ? ' i.'- .%.Ny I, - , *. . ~ .
'? "
, . s ' ; %.*, .
Mi~
ioA g, -
- l. . s. s . . .
j . ~
k) -
, ae w eeuy
. '. . h.
...j..,..r.>...
u we u-m
,b; ){f&f?m.iy -
, Ne, ;*.
' Cl- y Q
L:i.7.
i.
.! ' : . E. a,a so
~ .
. .s%g ,.y 7l, w:
u.
- .r'.
. e. :.t. t f,*
n.
I,~e
., : * /. 6 Qg > . + .q, . . .
- r. j. +
7:
n w. ,.&. v.. :,~;d. ;3.;. ;;. v. , 3 .. _
,, w e . , ,z . ,
u,* -
- ,. g. n., n
', c. ; - .
.: .. . *-.. m. .
g.
. rc ..v.- .) . , h ' f,..v;5.f .. o 2.f .. ., .
-u N
O' ( .
. ;y v .s ys ,. _n%.,
,s b.,'.cf,vw'$.f. .< ...<.....
r,Le,q *.
. ,li., ,
U#Il ..,D.,*'..,
n .*. r:+.r ..*,"**y n
<~
-s y-d w" m yv, C
~ y,
.' w y . . . l ,,, -
[ .
- .17 e 6
' A'e's a , *. mg-~ ke - . .
gam e' - s'.- a.
t%
t
, y?* a.. ,< .N.;
. . .f . . .
- c.
xg
, g. -
h . --
.y,... ~. .a m IS l
- :','-y.( , ~:Q ;g. ' / .
s,
.r ,
U ag q C 6.,
Eg a: yf '.* i. .
w , 3.)4.3 d ', p ,.o, .
%.,: / -
t.
a
.% ' ~. ' .' ; ,k n .a. O w
Q';. s
. c . 1 P ?.
un
- 6%w . . s; , .s . . :1.-.
e %,
wo , '?
b.
' . ,[b.
- W.CY.
WA .3 f g.,-
~.
.....i~,.
. , . ..i.e
. ,...,g. ,., . . :.
,s*
u g g m 4:- .
uo,
.r . .y 1.,.+,,. w.e .
. c. . - ...--~ , .-l. g, .yy.i -
aw, 5 ,.
.c b .ys. < .
r c,y. .
q '. &*w
' - k,a , .g
.c g ; . . . ...! c.
. ,j, . ' ' N. C y
.,: , r. . 4 ., ,y w
- .g,
. --t ~
.:?.',.}bqLoj:' x ? -
.~ oue
~. ' ' 9 *. .h. -
. e ,'./
'.,* 2cc
.; > v..'
as ,
- g o
~ n .
g a*ex l , ,yg g w *
- . m-l ~'O i '
- 4. y O
' N %r i
o esumunus.,
t 4% g u ,
e, .*c . '
k" O W.s. "..
, w-k M bt
- nn y k,
1-
.je s
,. *g -
Ig
, ee- ~w
~. . 3;
' !h.J;g.
8
. .6 %, ,,.
n r '. g
- A #
I u j WN e'e.:
'E E
s ... p.. ,, . w q9 i:
e . . ,, . %
w : . o i,,,. k -;s . - /.nng=~. , , ... - ,*4m uJ w .
- ^ *# '/G i y w.
f
,x E w* *$
- I . ,]-
'. a *,-
, a
- 7N
- o. ./W -. ' f '4 . .n
[ s ..a, ;le., ' y,; , '..
S
'8 ;Pg*p g*,
J, g.,*.
w cc
"..'s*
, ? 3, ,s....,. '
f..' q. . :. *'
6' ,,' . S ,.
-.:...). s. aa*A k , ', . - .
., l.
,"a a, .%
A
,...'la d D :0
h N'
.m 3-hy3.f.'.h. N@Jhhhjj v h,h.jh.[yy:[-@
w . . ~ -
- e e
,. a.. . .
h.u2-At
.d. 6 5 f 4 .,t.r.. e..<p+w
% y -
...r a
v, gg a ;. .c. ; -. xaw ti, y.,
't Ef%f $}tW'3Mf%w;ge: - W'%*5.%5%st *[,g;djf &;)
Q ', Fh. . **
- d. Wyhs@..F..}*<e<
m ..
kg,. '
' +2 *. .:g.
e-
- 'e
.[p..[. . 3 - W e
- 'A7 f.%
4 . 1 *f .
8
~
c ax y,
a s' --
7,s; :;; o wN,.
IN'.?
rn r e ,'
- O.I uu
[ .m ,, p,A,~h. ' "' ./y,
- : .. o, . ,.. ,Y#f/(+.'r a
i b"e n.
, . .e., e,
../ . Ie4 L.v
~
r
. . z s h s s,,;;3
.,, . c .
<:.'r.'
- '. l,,' p 08.Qt, . //p/ *'
n y ,f a .
- . L :Y * '
.l*
, s., y.-
h -
( p o' .
. .,f :- c,, .s a c * .
1
.a. .
- gu tM M* %
.X "
- l.' $C C
- f ,-i.,Lc i8 y L. ' ' 3 ' " ,f 4' ' ' F e .j st,6 p ,,d a g .5.s*
4
.y N n .m n g;y y y~
y}
t>: - .
h c 5
s * .' @$ I rN'!.* of0
, . . .* py a u P-
., .. lgf
- LC C.
_. 4 .'
- e. ww[;$' j n.m'y Ed~ le m=
g_ m y.. a=
n 4-gc: >. w' u.
p ' i Md e**
b[,y ,,
. c,
% v/w ih.k< f /;*) *Uh c c. .
/4. ;c; . . .n 22 C
g .
~ g . .c .w Z. *.
.s E 6 s e ,! ,s ..
.. 7
- r. cce
. ,g 7 -
{'f hy . AQQ' M...G.R , f,Y.h&. G !r,Y p::. n %~t
~ ~
a hk cnw MY ';g:
f 't}l "'
. ]?) t@LT
~
0.
s y :.d.c x way.sc&@. .,7, r
t .; 2 i.?
- e n m
- ~
4+ .,qs.v.
WAw;+w- . e.
- g. , vqQq 4;f.A:-lHp 1-g l Ci l . *t ;;i :
. .-,, t g X 4.:,v :, M.. i h'- wte- Ch '/.p'Fg wu-
- yY
- i w;.4.:p' i.g .:>bf,'4 : W
,3f.utcMk c
w:Q C'y o @M"1 ,
5.-
S Q .q:=p 2.<.;; :. y .. % w pw
- m. . . w t i t4 . .N.g;e:
m .,. .s gp%g.. ,,..
s f w. j iY a) ' x. > ~ . 'a.
_' i; . ' ;{._ _. \ '? .jp p ,,. }* 4 T. .
- s. . .,,.
, ,r ; * .gg'.,';',. , . ,, ,
EM ., s - .fh ;r ' _
..; . in - 2
obsersations on Marl:3 CL-100 KDpt U-bind specisele
, espeeed t3 gaena irr:diatite.
- Dose kate trad/h)
Doea (rad) 4.2 a 108 93 a 10 ' 3.6 a 108 6.0 a 10' Cracks appear to specimen color is -
grow. light brown.
7 2.0 10 Cracks defiattely - -
growing. Specimen celer is tea.
2.5 a 107 >ne crack prop- - -
agated through epecinea.
3 6 a 107 Little additional - -
track propagation.
Specineas still flesible.
4.5 a 107 , Large crack at - -
. spea of U-bend continues to propagate.
. $pecimens had elight oder.
1.7 a 108 (a) - Specinea color dark brown.
'4.7 a 10 s (a) Specines color a med. brown. One crack growing.
3.3 a 108 (a) Several cracks -
growing ta sise.
9.5 a los (a) Little additional crack propagettoa.
Specimens have moderate arosa but are still dry end partly flesible.
j 2.0 a 10' (a) (a) lascimes becesing sticky. Small shtay areas developing.
5.0 a 10 ' (a) (a) specimen very sticky, brown /
black color.
Strong arosa noticed.
1.0 a 1038 (a) (a) sea 11 surface bubbles form en original shley areas.
1 5 a 1038 (a) (a) Kany bubbles now seen on surface.
Specimen black.
2.9 a 1038 (a) (a) 7ests torsina'ed.
I Specimens coe-J pletely brittle, no longer sticay.
1 (a/ Dese not yet reathed.
<l j
4 A
l i
a a a i A ~ B ['g C ,
I b ,% -
s c b g , c ,.
b H
J c
- ; s .. c .
7 5, # ) C j .,'$-Z f .I
,j ['.'..' . 1 n t t, a pj
), /
- ev _- '
.m
?,)j ;/;l
' ~
I- , flii;{p;. %
h
~ *3 , *. :' _ -
, - s i}n$..; ' ,.h p s: .y g.;
.\ ' i=. y R?f(CL
' @ >W i
- A 'T <
, .. -@@% i
- aa,i
% I ~ j.r.hM .f W Yi jf.G:
y df3MO.,I
.. 'g;-
- ~.., T1 , (Mhi sq y
, , .: ,, y
' % ... \ ., / J SY' '
eff,1
,i, r .
- y'm*.mdlQ
. -w . . .* V fa e * . > rc F - ;
'h f ,j 1 -
's -
4 >
y 1
i $
l . .
i b
l h l a c l
.l Appearance of Type I (a), Ty p II (b) and Type III (c) Marlex CL-100 IIDPE U-bend specimens 2 gamina irradiated to 2.1 x 10 rad (A), 1.3 x 10 # rad (B), and 6.7 x 10e rad (C). Individual unirradiated Type I, Type II and Type III control specimens are shown at the bottom of the figure. Magnification 0.8 X.
t l
GRHHR-IRRRDIRTION TEST 5 DN HDPE U-BEND 5 I
GRHHR DOSE RRTE NUMBER RND TYPE *0F SPECIMEN CRRD/HR) TYPE I TYPE II TYPE III B B B 8
! 1.4 x 183 8 8 8
! 8.4 x 18 3 8 8 8 4.5 x 1B 5 8 8 8 l
- TYPE I - OXIDIZED SURFREE ON RPEX OF I
E U-BEND
! TYPE II -
OXIDIZED SURFREE REMOVED
! PRIOR TO U-BENDING l
TYPE III - NON-0XIDIZED SURFREE ON
- RPEX OF U-BEND l
O 0 e *
y .
WD
= ,
D f , ,li Eii .
^N Ql DMD#
- g kJ M. $, _ D _ !a h [ M M !!f, n
- 3 ll=i I
l l
l
G 8
m g I
= .
e m.g.
D A :::=: 2 - 8
-A el.h l
Y\ '
-a
_g
%. = %. = %. .
I, g. l
\
il l'
.1 ,.
i *
. - , _ . _ .. = .i I
i
4
. SUMHRRY DF ERREKING BEHRVIOR IN TYPE I HDPE U-BEND 5 :
ERREK ERREK l ENVIRONMENT INITIRTION7 PROPRGRTION7 RIR YE5 YE5 '
1.4 x 103 rad /h CRid YE5 YE5 !
8.4 x 103 rad /h CRid YE5 YE5 i
! 4.4 x 103 rad /h CRir) YE5 YE5 l 2.1x10 3 rad /h CIn i
sealed mixed bed '
IX resin) NO NO l DIN YES, but less YES, but less than for air than for air l N2 IN PROG. IN PROG. l VREUUH IN PROG. IN PROG. !
s !
i I l l
NOTE: No crack initiation or propagation ever found in irradiated or unirradiated Type II and III l specimens. )
. i l
EREEP - RUPTURE TESTS ON HDPE BR5IE DRTR NEED5 FOR ANRLYZING EREEP DEFORHRTION IN HIC'S INELUDE:
l o EREEP STRRIN CELONGRTION) WITH TIME l l
o EREEP FRILURE TIME l TEST VRRIR8LES INCLUDE: l l
o BRTEF-TO-BRTCH VRRIRTIONS IN HDPE I
o SPECIHEN SURFREE PREPRRRTION !
o RPPLIED STRESS -
o TEST ENVIRONMENT i o PRESENCE OF GRMMR IRRP.DIRTIOi CFY 1988) !
l:lI
- - - i - - -
0 I
_ I 0 4
1 r
e t
a
_ w r 0 1 -
- I 0 d 2
1 e
z i
n o
i e
d d
0 n a
1 I 0 0 r 1 i a
n i
C 0
0 2
~ 0 i 1 0) t a
0 (h
+ E E
P D
MI H T
_ E P
+ 0 4
1 DlW 0 L C
HD V O 0 6 x WN e EI l N r a
E M P r DR I o HA D a f WN 0 s i
EI N + i 0
4 r e
v u
E - c PR OI p e
HA m A e r
DN LI C
O o 0 i
S t
0 .
S) 5 4 EaP 6 3 R
TM 9 0 S( 1 t
- - O -
0 0 0 0 0 0 0 0 0 O 0 N 8 7 6 5 4 3 2 1 1
_ _# . - e$
e o
N 4 4 6 4 X+
6 E -
i !8
<t i 9
E 04 % +
0
- 40 3
- +
- ,k g$m -
4 w
f 2
be b W a
- e q i .
l E 8
7 d
t
- l!
w 0
. O .
a O u O
+
4
+
,4 4
1 1 i t '
(%) NIVW1S d33W
l 1 I I 300 -
Z a 200 OXIDIZED SURFACE -
$ REMOVED m
Q_
tij tij o' 100 O
AS FABRICATED I I I I o 100 200 300 400 50.0 TIME (h)
Effeet of surface preparation on the creep behavior of Marlex Cte 100 HDFE in deionized water at a stress of 11.03 MFa.
(!Sd) SS381S o o o o o o o 8
o o o o o o o o N_.- 92 u2 E C2 ES o
_ i . . . . . . . o
- - u, 3
7~
7 3
x "
- - : o O -
7g
_ - u O a
- m -
7-
% ro c t o-w e
- o - s s=
e w =
g a
- ::s w
g 7
e w m d o cr: -
D H w w w O. H m
U N
o ae a_
E g
- . w u- -
r cr: -
u 1
= a a o w m
_ . a -
e o 3 cm - "
< rc so~
w- -
2
- 5 z 2.:5 2
- {
su o 4" o o x c_ o_ aE a e
":- w CD w
- w mom w z' +m- w- u th
- wJ wow- k3
_ & a& zw- :e
_ . o a x -
to n,
5 t t t t I 1
(_##
v ro cu o cn o
- 9 (Od W) SS381S
~%
h
I I I I OXIDfZED NON-OXID.
STRESS AS SURFACE SURFACE (MPa) FABRIC. REMOVED REMOVED 10.34 0 -
x 9.65 A A +
goo 8.27 V V -
n 7
go -
E E
w V I
O w
60 - 3 -
i w I 8
a u &
,+
e 40 -
d i ,A -
^
l 'b d '
/ ,o -
/
20 g' U
, o n n- , 7 i=
y' V Y I I i 1 4
O K)O 200 300 400 500 TIME (h) .
1 i Creep of Marlex CL-100 HDPE at room temperature in Igepal.
I._--,.-..,---.-,-,_.,-,_--... - . - - , _ - - - _ , . . , , . _ , - . ,,,....- _ , - -- ... .. ----- - ,_ . . . , - - , - . . - - - - - , , _ .
13 . ......., . . . . ...., . . .
. . .....i . . ....., . . . . . . .
- 1800 12 r
- 1700 11 .
- 1600 2 ^ -
' = e -
1500 -
@g 10 1.
1400 ~
0 0 E9 -
1300 E e m m
^
- OLD HDPE, TESTED IN AIR -
1200 0 -
^ OLD HDPE, TESTED IN IGEPAL A NEW HDPE, TESTED IN IGEPAL 1100 7,- 1 NEW HDPE, NON-OXIDIZED LAYER REMOVED, TESTED IN IGEPAL 1000 6 ' "' ' "' ' "' ' "' ' ' ' ' ' ' " "
2 5 1 10 10 10 10 10 RUPTURE TIME (h)
Batch-to-batch variations in the stress-rupture behavior of Marles CL-100 HPDE in Igepal Co-630 at room tes.perature.
__, --.------g--.----
9 a
9 9
e
(!sd) ss381s !
, O O o o o o o o '
o N
o o o o v to N -
c 1
C w
- I i i I i i I i 1 - O g L k o
" 1 z
_ (/) C/) Wo *
< _J J NW -
z z z 5 gw tT) -
o Wo W e o-y b'
W W & V) C/) Z W
& ' o. gy-3w i y
c/)
w WH oz -
g p H H
o_ w
- U N 1 N Q
- l a Q. m -
w o o o - o E
- I Z Z%m 5 3 3 W
! o o e J i W WU J i
d 3 o.J z za 2 _ , l ro e o a .a .z: l
- O-
_ a.,
C W $.;
l
" 3 i
=
H $kI e= -
u~ t w iti ct::
j gi W ** l :;
j a N CL c" '
4 o -> i 1
i -
-% gi we u ,
1.s *
! N N
" 4
- - 5, b= i,
] - .C EF l
) .
U t s ace =-
M eis O
I a
- - ~ &R w:
- ~
i 10
- d 3=;
4yl .
- - l l
i i i i i i _
l r0 N -
O CD CD N O ;
(odW) SS381s !
r I
i i
i l
e- --a w ,,---- - ----.- n . , - ~ . , - -e e,-, ,y g -,-,,w me,, w .. .---n .---,-,,---,-,------,a, - - - - - - - -
l I
s
} 13 .
i : i . i >
i .
12 -
4 o
l1 -
No *o 1600 .
^
- o. N V o -
1500 2
~ 10 -
\ - -
C 1400
- w 9 -
v-b -
(w 1300 m tr m y . AIR -
1200 E 8 -
o DlW F
^LSF -
1100
- 7 -
v OIL
=IGEPAL icoo
, I e I I : ! n 2 3 4 5 l 10 10 -
10 10 10 RUPTURE TIME (h) stress-rupture results for Marlex CL-100 NDPE tested at roon temperature in various environments.
i e i i i i e AIR o DlW oIGEPAL 120 ^ v OIL _
^LSF _
100 4 6 a a _
80 -
60 -
3 40 -
ne a y
R 80 -
O
~
d H
60 -
C1 0 8 40 -
O J' l
l20 -
100 -
80 -
- e , ,e _
60 -
,, O 40 -
- 1 _
20 -
0 7 8 9 10 ll 12 13 14 STRESS (MPa)
Ductility of Karlex CI.-100 HDPE during creep testing in various envaronments.
4.V _
s
7__
l* .
l i'
REEDHMENDRTIONS FOR FUTURE WORK l
- 1. DURNTIFIERTION OF STRESS RELRXRTION RATE 5 IN GRHHR IRRRDIRTION ENVIRONMENTS. TO DETERMINE !
i HOW IT EFFECTS ERREK PROPRGRTION RRTE. !
h
! 2. CONTINURTION OF VERY-LONG-TERM EREEP TESTS G-5 YRS.) FOR STRESSE5 IN THE RRNGE 500 - 1200 !
psi C4.N - B.27 HPa). :
I ,
! LOW-COST EFFURT TO DETERMINE WHETHER SIGNIFIERNT EREEP DEFORHRTION ERN DEEUR RT PROTOTYPIC l
! EONTRINER STRESS LEVEL 5.
l l 2 l 3. INITIRTION OF LONG-TERM G YRS) 50 RTTREK TESTS 9 .
l TO VRLIDRTE RECELERRTED TEST 5 EURRENTLY BEING RUN.
i 4. PUREHRSE R CHICHIBU HIC RND ERRRY OUT EDHPRESSION i TESTS RFTER LONG-TERH LOW-DO5E-RRTE t~12 3 RRD/H) !
GRHHR IRRRDIRTION TO CHEEK EFFECTS OF POLYHER G l GENERRTION.
- _ - -