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Annual Report of the Canadian Section of the International Society of
Soil Mechanics and Foundation Engineering
NATIONAL RESEARCH COUNCIL OF CANADA
ASSOCIATE COMMITTEE ON SOIL AND SNOW MECHANICS
ANNUAL REPORT of t h e C A N A D I A N SECTION of t h e I n t e r n a t f o n a l S o c i e t y
o f
S o f l Mechanicsand
Foundation E n g i n e e r i n g ( J u n e 1950-
June 1 9 5 1 )SOIL MECHANICS BULLETIN NO. 2 ( T e c h n i c a l Memorandum No, 2 2 )
Ottawa October, 1951
FOREWORD
-
T h i s Annual R e p o r t c o v e r s t h e a c t i v i t i e s o f most o f t h e Canadian members o f t h e I n t e r n a t i o n a l S o c i e t y o f S o i l Mechanica and ~ ~ ' o u n d a t i o n E n g i n e e r i n g , f o r t h e p e r i o d J u n e 1950 t o J u n e 1 9 5 1 , I t s p r i m a r y p u r p o s e i s t o s e r v e a s a n a n n u a l r e p o r t o f t h e C a n a d i a n S e c t i o n o f t h e S o c i e t y , a s r e q u i r e d b y s t a t u t e s . I t s p u b l i c a t i o n at t h i s t i m e e a c h y e a r w i l l s e r v e a n o t h e r p u r p o s e , however, by k e e p i n g C a n a d i a n s i n f o r m e d of t h o s e s o i l m e c h a n i c s i n v e s t i g a t i o n s w h i c h a r e b e i n g c o n d u c t e d i n t h e i r own c o u n t r y I n t l i i s way, it w i l l a s s i s t i n overcoming t h e
n a t u r a l h a n d i c a p o f f e r e d b y t h e w i d e s p r e a d g e o ~ r a p h i c a l d i s t r i b u t t o n of s o i l m e c h a n i c s work i n t h i s c o u n t r y I n t h i s , it w i l l supplement, Annual C a n a d i a n S o i l lvlechanics C o n f e r e n c e s , w h i c h have now b e e n
h e l d f o r f o u r y e a r s u n d e r t h e a u s p i c e s of t h e A s s o c i a t e Committee on S o i l and Snow b i e c h a n i c s ,
T h e o r i e s , I l y p o t h e s e s , C o n s i d e r a t i o n s o f a G e n e r a l C h a r a c t e r
D r ,. Norman W , McLeod, b e p a r t m e n t o f A s p h a l t Technology, i m p e r i a l
O i l ~ i m i t e d , T o r o n t o
Norman Vu, McLeod, k d i s c u s s i o n of P r o f e s s o r
W ,
S o H o u s e l ' s p a p e r" i n t e r p r e t a t i o n o f T r i a x i a l Compress i o n ' T e s t s on G r a n u l a r ~ v I i x t u r ~ e s " ,
P r o c e e d i n g s , The A s s o c i a t i o n o f A s p h a l t Paving T e c h n o l o g i s t s , Voi 1 9 , P e b r u a r y , 1950; a l s o i n Symposium on T e s t i n g S o i l s Under T r i a x i a l Loading, American S o c i e t y f o r T e s t i n g I v i a t e r i a l s , J u n e , 1 9 50
I n t h e s e two s e p a r a t e d i s c u s s i o n s disagreement i s e x p r e s s e d w i t h P r o f e s s o r t i o u s e l ~ s two g e n e r a l c o n c l u s i o n s t h a t h e would a c c e p t t h e Coulomb e q u a t i o n and lblohr e n v e l o p e f o r t h e a n a l y s i s o f d i r e c t s n e a r t e s t d a t a , b u t would r e j e c t them f o r t h e a n a l y s i s of d a t a from t h e t r i a x i a l c o m p r e s s i o n t e s t . I n h i s two d i s c u s s i o n s , t h e w r i t e r e n d e a v o u r s t o p o i n t o u t why t h e s e two c o n c l u s i o n s a r e i n c o m p a t i b l e w i t h e a c h o t h e r ,
ljorman b, ihcLeod, 14 d i s c u s s i o n o f t h e p a p e r by
F, M
, Hveem andi i , d o D a v i s on " ~ o m e Concepts Concerning T r i a x i a l Compression ' l ' e s t i n g o f i i s p h a l t Paving i d i x t u r e s and Subgrade IVlaterials"
,
Symposium onT e s t i n g S o i l s Under T r i a x i a l Loading, American S o c i e t y f o r ' T e s t i n g l v I a t e r i a l s , J u n e , 19bOrj
The a u t h o r s r p a p e r s t a t e s t h a t v a l u e s f o r c and
$
c a n be o b t a i n e d f ronl Iiveem s t a b i l o m e t e r d a t a . The w r i t e r 3 d i s c u s s i o nd e ~ n o n s t r a t e s th a t b e c a u s e Ilveern s t a b i l o m e t e r d a t a p r o v i d e a c u r v e d r e l a t i o n s h i p between t h e p r i n c i p a l s t r e s s e s , t h e method d e s c r i b e d
i n t h e a u t h o r s D p a p e r g i v e s w i d e l y v a r y i n g numerical v a l u e s f o r c and
$,
depending upon t h e p o r t i o n of t h e s t a b i l o r n e t e r c u r v e employed f o r t h e i r e v a l u a t i o n ,Norman
W.
l ~ ~ c l e o d , "The Ulohr Diagram and Coulomb Lquat i o n " , P r o c e e d i n g s , Eighway f i e s e a r c h B o a r d , Vol, 30, 1 9 5 1 ,R e f e r e n c e i s made t o t h e c u r r e n t d i f f e r e n c e o f o p i n i o n t h a t a p p e a r s t o e x i s t c o n c e r n i n g t h e s i g n i f i c a n c e o f t h e Coulomb e q u a t i o n , t h e if~ohr d i a g r a m , and t h e r e l a t i o n s h i p between them, The p a p e r r e v i e w s t h e s i m p l e s t c a s e , t h e s t r e s s i n g of c e r t a i n s o i l s o r s i m i l a r m a t e r i a l s f o r which t h e Coulomb, p r i n c i p a l s t r e s s , and idohr e n v e l o p e s a r e s t r a i g h t l i n e s . T w o p r i n c i p a l c o n c l u s i o n s a r e p r e s e n t e d Because o f t h e i n c r e a s i n g i n t e r e s t i n t h e u s e o f t h e t r i a x i a l t e s t f o r t h e s o l u t i o n o f highway and a i r p o r t e n g i n e e r i n g p r o b l e m s , it i s c o n s i d e r e d i m p o r t a n t t h a t agreement s h o u l d be r e a c h e d r e g a r d i n g t h e s i g n i f i c a n c e of t h e lhohr d i a g r a m f o r t h e a n a l y s i s o f t r i a x i a l d a t a , and c o n c e r n i n g t h e n a t u r e o f t h e r e l a t i o n s h i p between t h e Coulomb and Mohr d i a g r a m s , The p a p e r i s i n t e n d e d t o promote d i s c u s s i o n h a v i n g t h e s e o b j e c t i v e s i n view,
SECTION
I1
L a b o r a t o r y I n v e s t i g a t i o n s
D i v i s i o n of B u i l d i n g R e s e a r c h , N a t i o n a l R e s e a r c h
--
C o u n c i l o f Canada, Ottawa ( illembers l i s t e d i n Appendix)There i s l i t t l e i n f o r m a t i o n c o n c e r n i n g t.he e n g i n e e r i n g p r o p e r t i e s of v a r v e d c l a y s , w h i c h a r e e n c o u n t e r e d i n c o n s t r u c t i o n
i n many p l a c e s i n Canada, A s t u d y of t h e s e u n u s u a l s o i l s h a s t h e r e f o r e been i n i t i a t e d , Because of t h e i r complex n a t u r e , t h i s i s n e c e s s a r i l y a long.-term p r o j e c t , An e x c e l l e n t e x p o s u r e of v a r v e d s o i l s h a s b e e n u n c o v e r e d w i t h t h e development o f S t e e p hock I r o n k i n e i n n o r t h w e s t e r n O n t a r i o , and w i t h t h e f u l l c o - o p e r a t i o n of t h e m i n i n g company, a good o p p o r t u n i t y h a s b e e n p r o v i d e d Lo s t u d y t h e s o i l s i n t h e f i e l d , To d a t e , s t u d i e s have been d i r e c t e d t o w a r d s d e t eramining . v a r i a t i o n s i n t h e s e p a r a t e d a r k and l i g h ~ l a y e r s o f t h e s o i l t o a s s e s s t h e e f f e c t of t h e s e v a r i a t i o n s on t h e p r o p e r t i e s o f t h e o v e r a l l s o i l mass, I n d i c a t o r p r o p e r t i e s have beer] i n v e s t i g a t e d , I a i d e n t a l t o t h e mining o p e r a t i o n s a t S t e e p iiock, a l a r g e amount o f h y d r a u l i c s t r i p p i n g of v a r v e d s o i . 1 ~
i s done, ii s t u d y h a s been made of t h e e f f e c t of d r e d g i n g on t h e
s t r u c t u r e and g r a i n s f z e d i s t r i b u t i o n o f t h e s o i l , p a ~ t i c u l a r k y a s a f f e c t i n g s e d i m e n t a t i o n T h i s s t u d y was c a r r i e d o u t by a g r a d u a t e s t u d e n t ( ~ e p o r t e d by l l r .
W ,
J , h'dan)SECTION 111 F i e l d I n v e s t i g a t i o n s
-
T e s t i n g L a b o r a t o r i e s , Department o f P u b l i c Works (Members l i s t e d i n ~ p p e n d i x ) D u r i n g a s e r i e s of t e s t s on l o c a l c l a y s i t was found t h a t t h e r e s u l t s of u n c o n f i n e d c o m p r e s s i o n t e s t s on t h e uppermost 8 t o 1 0 i n c h e s o f t h i n w a l l t u b e s a m p l e s were e r r a t i c , and subsequent, l o n g i t u d i n a l s e c t i o n i n g of t h e samples showed a p p a r e n t l y i s o l a t e d p o c k e t s o f w a t e r , mud andwax,
w i t h no v i s i b l e connectfor_ w i t h t h e e x t e r i o r o f t h e s a r n p l e , C a r e f u l e x a m i n a t i o n of a numbel- o f + h s s a t e s t specimens and of t h e d r i l l i n g p r o c e d u r e u s e d i n d i c a t e d t h a t t h e f l u s h i n g j e t u s e d tao c l e a n o u t t h e h o l e p r i o r t o i n t s c d u c t i o n o f t h e t h i n - w a l l t u b e was o f s u c h power t h a t i t a p p a r e n t l y p e n e t r a t e d t h e ? r o u n d below, c r e a t i n g o r f o l l o w i n g e x i s t i n g f i s s u r e s t h e s e b e i n g s u b s e q u e n t l y c l o s e d by t h e r e m o u l d i n g a c t i o n2f chs
sample t u b e p e n e t r a t i o n and sample e x t r u s i o n , p r o d u c i n g an a p p a r e n t l y u n d i s t u r b e d and homogeneous sample The d i f f i c u l t y was s o l v e d by r e d u c i n g t h e power o f t h e j e t u s e d f o r c l e a n i n g o u t t h e b c r e h o l e C o n c u r r e n t l y w i t h t h i s problem some t r o u b l e was encoun. t e r e d w i t h h a r d e n e d p o c k e t s of wax a d h e r i n g t o t h e s i d e s of t h e t u b e a t o r below t h e s u r f a c e o f t h e s a m p l e , p r o d u c i n g d e f o r m a t i o n and r e m o u l d i n g on e x t r u s i o n T h i s was e l i m i n a t e d by w a r m k g t h s s u r f a c e of a l l t u b e s f o r some d i s t a n c e below t h e t o p o f t h e sample p r i o r t o e x t r u s i o n o f t h e s o i l > t o i n s u r e t h e c o m p l e t e removal of
wax ( R e p o r t e d by 1Vlr J , 'vVr h e e c e )
U n i v e r s i t y o f A l b e r t a , Edmonton (Dean K O la, Hardy, ivlr S o
H ,
~ i n c l s l r )---
The u s a f u l n e s s of t h e r e s i s t i v i t y methoa of s o i l e x p L o r a t ~ o n f o r f o u n d a t i o n p u r p o s e s h a s been s t u d i e d , The method g i . v a s v a l u a b l e r e s u l t s u n d e r some c o n d i t i o n s but u n d e r o t h e r s d i f f i c u l t i e s i n
i n t e r p r e t a t i o n a r i s e , pa-t. i c u l a r l g i n t h e l o c a t i o n s of g l a c i a l d e p c s i t s of a h i g h l y non - u n i f o r m c h a r a c t e r ,
Department ---- o f P u b l i c 'Norks
,
P r o v i n c e - o f A l b e r t a Edmonton 9i R , J , H o l l i n g s h e a d )
A
cone s o u n d i n g d e v i c e s i m i l a r t o t h a t o u t l i n e d byB a r e n t s e n ( P r o c e e d i n g s of l n t e r n a t i o n a l C o n f e r e n c e on S o i l liilechani"3~ and 2loundation d n g i n e e r i n g , Cambridge, 1 9 3 6 ) h a s been c o n s t r u z t ed The p r e s e n t i n t e n t i o n i s t o make s o u n d i n g s i n muskeg s o i l s on which hiehways w i l l be b u i l t and t h e n measure t h e s e t t l e m e n t of t h e s e highways o v e r a p e r i o d of t i m e It i s t h e n hoped t o c o r r e l a t e t h e
o b s e r v e d s e t t l e r n e n t s w i t h t h e r e s u l t s of t h e s o u n d i n g s
It,
may a l s o b e p o s s i b l e t o p r e d i c t t h e a p p r o x i m a t e s t r e n g t h of a mcskeg s o t h a t a s h e a r i n g f a i l u r e of muskeg by t h e weight o f a highway fiLl w i l l be a v o i d e d , Two s u c h s h e a r i n g f a i l u r e s have o c c u r r e d , at-.l a n a n a l y s i s a t one s i t e i n d i c a t e d t h e s h e a r i n g s t r e n g t h nf khemuskeg m a t e r i a l t o be 30 pounds p e r s q u a r e f o o t , An a n a l y s i s a t t h e o t h e r s i t e i n d i c a t e d t h e s h e a r i n g s t r e n g t h t o be a b o u t 7 0 pounds p e r s q u a r e f o o t , The a n a l y s e s were performed u t i l i z i n g % h e
i n f o r m a t i o n p r e s e n t e d by t h e f a i l u r e s ,
P r a i r i e Farm ftehab i l i t a t i o n A d m i n i s t r a t i o n , Department o f A g r i c u l t u r e uf Canada. S a s k a t o o n (Members l i s t e d i n A ~ ~ e n d T x )
An e a r t h r e s i s t i v i t y a p p a r a t u s f a s h i o n e d a f t e r t h e o r i g i n a l d e s i g n proposed by Weiner-i;ish=Hooney h a s been b u i l t , f o r u s e i n
s u b s b r f a c e - e x p l o r a t i o n , It u t i l i z e s t h e p r i n c i p l e t h a t t h e s p e c i f i c r e s i s t a n c e of any s o i l t y p e v a r i e s depending on i t s g r a i n s i z e +
m o i s t u r e c o n t e n t , m i n e r a l o g i c a l c o n s t i t u e n t s , s a l t e o n t e n t : and o t h e r f a c t o r s , The i n s t r u m e n t w i l l be u s e d f o r s o i l p r o f i l e
i n v e s t i g a t i o n s a l o n g t h e p r o p o s e d r o u t e o f t h e d i v e r s i o n c a n a l f o r t h e Hed R i v e r around t h e C i t y of Winnipego It w i l l be u s e d paaimasilg f o r d e t e r m i n i n g t h e d e p t h t o b e d r o c k where t h a t d e p t h i s w i t h i n
a p p r o x i m a t e l y 1 0 0 f e e t o f t h e s l ~ r f a c e
U n i v e r s i t y of Saskatchewan, S a s k a t o o n (IYlr,
B,
B,
T o r c h i n s k y ) Some work h a s b e e n done on d i f f e r e n t t y p e s of m o i s t u r e m e t e r s , The e l e c t r i c a l r e s i s t a n c e m e t e r , , t h e h e a t c o n d u c t i v i t y m e t e r , and t h e r a d i o a c t i v e n e u t r o n m e t e r have a l l been u s e d t,od e t e r m i n e s o i l m o i s t u r e c o n t e n t , The e l e c t r i c a l r e s i s t a n c e m e t e r h a s n o t g i v e n c o n s i s t e n t r e s u l t s - The h e a t c o n d u c t i v l . t y m e t e r
seems more promis i n g , However, insuf'f i c i e n t t e s t i n g h a s b e e n dons
t o a l l o w any d e f i n i t e a s s e s s m e n t o
A c o n s i d e r a b l e amount o f work h a s been done w i t h t h e n e u t r o n m e t e r and t h i s u n i t seems q u i t e p r o m i s i n g k radium-
b e r y l l i u m n e u t r o n s o u r c e i s u s e d t o p r o v i d e f a s t n e u t r o n s whfch a r e slowed down on p a s s i n g t h r o u g h m o i s t s o i l These slow m u t , - o n s bombard a s h e e t o f indium c a u s i n g i t t o become r a d i o a c t i v e The amount of r a d i o a c t i v i t y o f t h e indium can be r e i a t e d t o t h e m o i s t u r e c o n t e n t of t h e s o i l , r e g a r d l e s s of s o i l t y p e - . D r , J c \ I I o T L S p i n k s
of t h e U n i v e r s i t y of Saskatchewan s u g g e s t e d t h i s a p p r o a c h , exd t h e equipment u s e d i s v e r y s i m i l a r t o t h a t r e p o r t e d by D r B e l c h e r of C o r n e l l U n i v e r s i t y i n a r e c e n t p a p e r t o t h e Highway f i e s e a r c h Board, The same i n s t r u m e n t can De u s e d t o d e t e c t t h e wet; d e n s i t y of khe s o f l , r e g a r d l e s s of s o i l t y p e , u s i n g t h e same s o u r c e The geomet
-
r i c a l a r r a n g e m e n t of t h e equipment i s v e r y i m p o r t a n t a n d must be kept, c o n s t a n t i n ordela t o g e t c o n s i s t e n t r e s u l t sfwo n e u t r o n m e t e r s have b e e n b u i l t , and it i s hoped t h a t more i n f o r m a t i o n on f i e l d p e r f o r m a n c e of t h e s e u n i k s w i l l be
a v a i l a b l e a t t h e end of t h i s summer, The work on t h e n e u t r o n mete^
h a s been done by a p o s t g r a d u a t e s t u d e n t end f i n a n c e d by a g r a n t from t h e Saskatchewan R e s e a r c h C o u n c i l ,,
H y d r o - U l e c t r i c Power
-
Commission o f O n t a r i o , T o r o n t o (iik,D o
G o Watt, M r , W, Trow)The Comrniss i o n h a s b e e n p a r t i c u l a r l y i n t e r e s t e d i n deep s o u n d i n g methods f o r e v a l u a t i n g t h e l o a d c a p a c i t y of s o i l s , A comparison between t h e v a n e s h e a r t e s t e r and t h e u n c o n f i n e d
c o m p r e s s i o n t e s t i s b e i n g maden Agreement between t h e two methods Tor i n d i c a t i n g s h e a r i n g r e s i s t a n c e h a s b e e n o b t a i n e d o n l y w i t h s o f t c l a y s " T h i s s u g g e s t s t h a t i n t e r n a l f r i c t i o n s h o u l d be a c c o u n t e d f o r i n t h e more r e s i s t a n t c l a y s and c o h e s i v e s i l t s ,
The F o u n d a t i o n Company o f Canada L i m i t e d , IVlont r e a l
D,
L e a ) Some i n t e r e s t i n g i n f o r m a t i o n h a s been g a t h e r e d r e g a r d i n g t h e c o r r e l a t i o n between t h e s t a n d a r d p e n e t r a t i o n t e s t u s i n g aspoon sample, a p e n e t r a t i o n t e s t u s i n g a c o n i c a l p o i n t , t h e
l a b o r a t o r y u n c o n f i n e d c o m p r e s s i o n and t r i a x i a l t e s t s , f l.eld i n s i t u vane s h e a r s t r e n g t h t e s t and p l a t e b e a r i n g t e s t , One p r o j e c t ,
d e a l i n g w i t h t,he a n a l y s i s o f a b u l k h e a d and o t h e r w a t e r f s o n t s t r u c - t u r e s , i s s t ill i n p r o g r e s s , S i g n i f i c a n t c o r r e l a t i o n s have b e e n o b t a i n e d between t h e s t r e n g t h shown by s l i d e s , t h a t det-ermined i n t h e l a b o r a t o r y from u n c o n f i h e d c o m p r e s s i o n t e s t s , , and t h a t d e t e r m i n e d i n t h e f i e l d by i n s i t u vane s h e a r s t r e n g t h t e s t s ,
Measurements of d e f l e c t i o n , p o r e w a t e r p r e s s u r e and t i e r o d s t r a i n a r e b e i n g c o n t i n u e d ,
On t h e p r i n c i p l e ~ f t h e vane t e s t e r d e v e l o p e d i n Sweden and G r e a t E r b i t a i n , a d e v i c e h a s been d e v e l o p e d which a u t o m a t i c a l l y r l e c o r d s t h e s t r e s s - s t r a i n d i a g r a m f o r a s o i l , On t h e o n e p r o j e c t on which t h i s d e v i c e h a s been usgd it h a s p r o v e d Go be v e r y
v a l u a b l e s i n c e t h e r e s i d u a l s h e a r s t r e n g t h and t h e m a g n i t u d e o f t h e s t r a i n were q u i t e i m p o r t a n t ,
C o n s t r u c t i o n Borinf.,s L i m i t e d , M o n t r e a l (IfLr,
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iui, F a i r b a i r n ) On t h r e e b o r i n g jobs on t h e h a r b o u r f r o n t a t I i a m i l t o n , O n t a r i o , it was p o s s i b l e t o rnake p e n e t r a t i o n t e s t s , u n c o n f i n e d c o m p r e s s i o n t e s t s , and s h e a r t e s t s i n p l a c e w i t h a v a n e t e s t e r s o t h a t t h e u n c o n f i n e d c o m p r e s s i v e s t r e n g t h was t w i c e t h e s h e a r s t r e n g t h . Comparison of r e s u l t s i n d i c a t e d t h a t a l l o w a b l e b e a r i n g v a l u e s b a s e d o n t h e s h e a r t e s t i n p l a c e were somewhat h i g h e r t h a n t h o s e b a s e d on u n c o n f i n e d c o m p r e s s i o n t e s t s ( w h i c h depended i n p a r t on t h e amount of d i s t u r b a n c e o f t h e s p e c i m e n ) , Both t h e u n c o n f i n e d c o m p r e s s i o n and i n - p l a c e s h e a r t e s t s i n d i c a t e d b e a r i n g v a l u e s n e a r l y d o u b l e t h e maximum p e r m i s s i b l e v a l u e s b a s e d ont h e s t a r i d a r d p e n e t r a t i o n t e s t a s recommended by T e r z a g h i and Peck i n " S o i l Idechanics i n Ungineer i n g ~ r a c t ice'' T h i s p r o c e d u r e of making t h r e e t y p e s of t e s t h a s a l s o been c a r r i e d o u t a t S t , Hubert
and liiontreal i n k u e b e c , and Dartmouth i n Nova S c o t i a , w i t h s i m i l a r r e s u l t s .
A s a r e s u l t of t h e s e t e s t s , it i s c o n c l u d e d t h a t w h i l e no t e s t i s p e r f e c t f o r o b t a i n i n g l o a d b e a r i n g d a t a , p e n e t r a t i o n t e s t s i n c o h e s i v e s o i l s seem t o l e a d t o t h e o v e r d e s i g n o f f o o t i n g s , c a u s i n g a 1 0 0 p e r c e n t i n c r e a s e i n a r e a of f o o t i n g s o v e r t h o s e d e s i g n e d on t h e b a s i s o f t e s t s on t h i n - w a l l t u b e s a m p l e s , o r on t h e b a s i s of vane t e s t s , A l t e r n a t i v e l y , p e n e t r a t i o n t e s t s may l e a d t o t h e s e l e c t i o n o f a p i l e f o u n d a t i o n w h e t h e r t h i s i s w a r r a n t e d o r n o t , These c o n s i d e r a t i o n s a r e of c o u r s e q u i t e a p a r t from t h e q u e s t i o n o f s e t t l e m e n t due t o c o n s o l i d a t i o n Div
-
i s i o n o f B u i l d i n g R e s e a r c h , N a t i o n a l R e s e a r c h C o u n c i l of Canada, Ottawa (Members l i s t e d i n Appendix)R e s e a r c h on T o r o n t o Subway C o n s t r u c t i o n : A member of t h e s t a f f o f t h i s D i v i s i o n was s t a t i o n e d s i n c e t h e f a l l of 1949 on t h e c o n s t r u c t i o n o f C a n a d a ' s f i r s t subway i n T o r o n t o , O n t a r i o , H i s work, done i n
c o - o p e r a t i o n w i t h t l i e s t a f f o f t h e T o r o n t o ' T r a n s p o r t a t i o n C o m r ~ i s s i o n , c o n s i s t e d m a i n l y o f a p p l i e d r e s e a r c h i n t h e f i e l d s of s o i l m e c h a n i c s , g e o l o g y and s t r u c t u r a l e n g i n e e r i n g , d u r i n g t h e c o n s t r u c t i o n o f t h e 4$-mile r a p i d t r a n s i t l i n e , which i s b e i n g b u i l t p a r t l y by t h e c u t - a n d - c o v e r method and p a r t l y i n open c u t s . 1V1ore s p e c i f i c a l l y , t h e work i n s o i l mechanics c o n s i s t e d i n r e c o r d i n g a complete s o i l p r o f i l e a l o n g t h e r o u t e o f t h e subway, The T o r o n t o s o i l s c o n s i s t , m o s t l y o f g l a c i a l d e p o s i t s ( c l a y e y and s a n d y t i l l s w i t h i n t e r g l a c i a l s a n d s j s i l t s and v a r v e d c l a y s ) , which have b e e n e x t e n s i v e l y s t u d i e d by g e o l o g i s t s from many c o u n t r i e s b u t whose s t r a t i g r a p h i c p o s i t i o n
i s s t ill p a r t l y unknown, The c o l l e c t i o n of s o i l i n f o r m a t i o n was, however, a l s o done from an e n g i n e e r i n g p o i n t of v i e w and t s h e r e f o r e
i n c l u d e d t h e t e s t i n g o f samples a t a s p e c i a l s o i l mechanics
l a b o r a t o r y . . Some work was a l s o done i n c o n n e c t i o n w i t h compaction c o n t r o l of b a c k f i l l m a t e r i a l s , e a r t h p r e s s u r e s , v i b r a t i o n s due t o p i l e d r i v i n g , and s o i l t e m p e r a t u r e s . ( H e p o r t e d by l d r ,
W.H,
S h r i e v e r ) S o i l T e m p e r a t u r e s : The v a r i a t i o n of s o i l t e m p e r a t u r e s i s o fi m p o r t a n t e n g i n e e r i n g s i g n i f i c a n c e i n Canada, Many economic p r o b l e m s r e q u i r e f o r t h e i r a n a l y s i s a knowledge of t e m p e r a t u r e v a r i a t i o n and f r o s t p e n e t r a t i o n i n s o i l s , For t h i s r e a s o n a l o n g . . t e r m p r o j e c t h a s b e e n Launched i n an a t t e m p t t o i n c r e a s e t h e knowledge o f f a c t o r s i n v o l v e d , s o t h a t g r o u n d t e m p e r a t u r e s may be r e a s o n a b l y p r e d i c t e d and p o s s i b l y c o n t r o l l e d t o some e x t e n t , lilleasurements o f s o i l t e m p e r a t u r e s , s t a r t e d a t t h e U n i v e r s i t y o f T o r o n t o i n 1945, have been c o n t i n u e d by t h e l j i v i s i o n o f B u i l d i n g R e s e a r c h s i n c e 1 9 4 8 , F i e l d measurements t o d a t e h a v e a t t e m p t e d t o e v a l u a t e t h e e f f e c t of s o i l t y p e , d e n s i t y , and snow c o v e r . For t h i s p u r p o s e t e m p e r a t u r e v a r i a t i o n s a r e b e i n g measured i n o u t d o o r t e s t p i t s , b a c k f i l l e d u n d e r c o n t r o l l e d c o n d i t . i o n s
iVIeasurements a r e t a k e n i n b o t h sand and c l a y , w i t h and w i t h o u t s n o w - c o v e r , In a d d i t i o n , some measurements have been made u n d e r c i t y s t r e e t s , t o g e t h e r w i t h r e c o r d s o f f r o s t d e p t h s d e t e r m i n e d by e x c a v a t i o n , ( R e p o r t e d by IVlr, C
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AP r o g r e s s . R e p o r t u , P r o c e e d f n g s Highway H e s e a r c h Board, V o i , 29, December, 1 9 4 9 -
T h i s p a p e r o u t l i n e s t h e more i m p o r t a n t economic a s p e c t s o f s o i l t e m p e r a t u r e i n v e s t i g a t i o n s , b r i e f l y r e v i e w s h i s t o r i c a l work on t h e problem, d i s c u s s e s some of t h e c o m p l i c a t i o n s and
unknown v a r i a b l e s i n s o i l t e m p e r a t u r e p r e d i c t i o n , and r e c o r d s t h e Canadian work now i n p r o g r e s s .
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Crawford, " S o i l T e m p e r a t u r e s-
A Review o f P u b l i s h e d ~ e c o r d s " , P r o c e e d i n g s , Highway H e s e a r c h Board, Vol, 3 0 ,J a n u a r y , 1 9 5 1 , T h i s p a p e r i s a r e v i e w of 7 8 p a p e r s r e l a t e d t o s o i l t e m p e r a t u r e s t u d i e s d u r i n g t h e l a s t c e n t u r y - The c o n t r i b u t i o n o f e a c h p a p e r i s n o t e d u n d e r s e p a r a t e s e c t i o n s d e a l i n g w i t h e a c h of t h e v a r i a b l e s known t o a f f e c t s o i l t e m p e r a t u r e , , F o u n d a t i o n s i n P e r m a f r o s t : A s t u d y o f f o u n d a t i o n s i n p e r a e n n i a l l y
--
f r o z e n g r o u n d [ p e r m a f r o s t ) was i n i t i a t e d d u r i n g t h e summer of 1950,> A four-man p a r t y under t h e j o i n t s p o n s o r e h i p o f t h e D i v i s i o n a n d t h e D i r e c t o r a t e of d n g i n e e r Development of t h e Department o f N a t i o n a l Defence ( ~ s m y ),
s t u d i e d c u r r e n t p r a c t i c e and p e r f o r m a n c e of b u i l d i n g f o u n d a t i o n s on p e r m a f r o s t i n t h e Mackenzie R i v e r r e g i o n of t h e LVorthwest T e r r i t o r i e s npproximat e l y . 2 5 0 b u i l d i n g s i n 1 2 s e t t l e m e n t s were s t u d i e d on t h e 1 0 0 0 - m i l e t r i p , I n f o r m a t i o n o b t a i n e d i n e a c h b u i l d i n g s t u d y i n c l u d e d l o c a t i o n , c o n s t r u c t i o n h i s t o r y , a s k e t c h p l a n , photograaphs, s o i l a n d p e r m a f r o s t c o n d i t i o n s , d e t a i l s of f o u n d a t i o n s , f l o o r , c e i l i n g , , w a l l and r o o f " u t i l i t i e s and f a i l u r e s , CVhi1.e t h e need f o r d e s i g n d a t a i n p e r m a f r o s t f o u n d a t i o n s i s c o n s i d e r e d g r e a t , it i s found t h a t much work r e m a i n s t o be done i n t h e development of s i t e s 6 1 e c t i 0 n p r o c e d u r e s and t e c h n i q u e s ,B e l i e v i n g t h a t a e r i a l p h o t o g r a p h s o f f e r a p a r t i a l s o l u t i o n t o s i % e s e l e c t i o n problems i n t h e v a s t and r e l a t i v e l y i n a c c e s s i b l e r e g i o n s o f t h e N o r t h g a f i e l d t r i p t o t h e N!a@kenzie R i v e r r e g i c n
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i n v e s t i g a t e t h i s p o s s i b l e c o r r e l a t i o n i s b e i n g u n d e r t a k e n
in
t h e summer of 1 9 5 1 j o i n t l y with Purdue U n i v e r s i t y r( R e p o r t e d by M r J , A P i h l a i n e n J ,A, I j i h l a i n e n " m i l d i n g E'oundat i o n s on P e r m a f r o s t , ~vlackenzis V a l l e y , N.'di2l'.l', DBic No. 2 2 N a t i o n a l H e s e a r c h C o u n c i l of Canada,
J u n e , 1951,
T h i s p a p e r r e p o r t s on f i n d i n g s c o n c l u s i o n s and recorn- rnendat i o n s o f t h e 1950 i n v e s t i g a t i o n ,
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s u g g e s t s t h a t ;na.jor c h a r a c t e r i s t i c s of t h i s s o i l m i g h t b e s t be
i n v e s t i g a t e d u n d e r t h r e e h e a d i n g s :, t o p o g r a p h i c a t t r i b u t e s , s u r a f a c e c o v e r a g e and s u b s u r f a c e cornposit i o n - Among t h e s e , s u r f a c e c o v e s a g e
i s t h e most f r e q u e n t l y u s e d i n r e c o g n i z i n g d i f f e r e n t t y p e s of
o r g a n i c t e r r a i n , H c l a s s i f i c a t i o n key t o s u r f a c e coverage has now been c o n s t r u c t e d t o e l i m i n a t e c o n f u s i o n i n terminology and t o
f a c i l i t a t e and s t a n a a r d i z e r e f e r e n c e t o c a t e g o r i e s of coverage,
This key u t i l i z e s n i n e cover t y p e s , e a c h being a f u n c t i o n of t e x t u r e , h e i g h t and growth of t h e v e g e t a t i o n m a t e r i a l , Combinations of
t h e s e f a c t o r s provide formulae which i n d i c a t e t h e f i e l d coverag8 c o n d i t i o n o v e r l y i n g t h e p e a t y f o u n d a t i o n , The system o f r e f e r e n c e
i s now being a p p l i e d i n t h e f i e l d and t h i s coverage formula 1 2 b e i n g r e l a t e d t o t h e g r o s s composition of t h e o r g a n i c m a t e r A l a l b e n e a t h ,
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o f Canada, S a s k a t o o n (Members l i s t e d i n Appendix)S l o p e s i n S w e l l i n g S h a l e s : F o r a number of y e a r s a n i n v e s t i g a t i o n h a s b e e n c a r r i e d o u t on t h e p r o p o s e d s i t e of a l a r g e e a r t h dam on t h e S o u t h Saskatchewan R i v e r , T h i s dam w i l l be 210 f e e t i n h e i g h t and i s f o u n d e d o n about 90 f e e t o f f i n e t o medium sand which
o v e r l i e s a s o f t s h a l e b e d r o c k , While t h e p e r v i o u s s a n d p r e s e n t s a problem, t h i s i s s t r a i g h t f o r w a r d a s compared w i t h t h e i n s t a b i l i t y of t h e Bearpaw s h a l e which o c c u r s on t h e b a n k s , and t h r o u g h which t h e a p p u r t e n a n t s t r u c t u r e s must be p l a c e d . 'This i s a h i g h l y s w e l l i n g s h a l e w i t h v e r y h i g h A t t e r b e r g l i m i t s , It h a s p r c v e d +,o be a n e x t r e m e l y u n s t a b l e m a t e r i a l and e x t e n s i v e s t u d i e s a r e b e i n g c a r r i e d o u t t o d e t e r m i n e t h e s l o p e s a t which it may be s t a b l e , The P . F , H . A , i s c o - o p e r a t i n g w i t h t h e U n i t e d S t a t e s Corps o f E n g i n e e r s i n s t u d i e s on t h i s m a t e r i a l
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neous e a r t h dams i s b e i n g i n v e s t i ~ a t e d , It h a s been f o u n d t h a t t h e p e r c e n t age o f f a i l u r e s o f homogeneous i m p e r v i o u s f i l l s i s g r e a t e r t h a n t h a t of f i l l s o f zoned s e c t i o n s , It i s hoped t o i c v e s t i g a t e t h o s e dams which have f a i l e d , a s w e l l a s some o f t h e e x i s t i n g
homogeneous dams t o d e t e r m i n e i f t h e r e a r e any b a s i c common c a u s e s f o r t h e f a i l u r e s ,
G r e a t e r Ninnipeg Dgking Board, Winnipeg ( M r , C . H , Templeton!
The work of t h e Board h a s c o n s i s t e d of t h e c o n s t r u c t i c ~ n of 2 5 m i l e s o f c l a y d i k e s , s t a b i l i z e d f i l l d i k e s , c o f f e r d a m t y p e d i k e s composed o f two rows o f wooden s h e e t p i l i n g f i l l e d w i t h s a n d , and r e i n f o r c e d c o n c r e t e f l o o d w a l l s a l o n g t h e banks o f t h e Red H i v e r i n G r e a t e r Winnipeg, The banks of t.he Red H i v e r i n
t h i s v i c i n i t y a r e v e r y u n s t a b l e and s u b j e c t t o a "draw dowr," e f f e c t when t h e w a t e r l e v e l r e c e d e s , illany i n t e r e s t i n g f e a t u r e s have been e n c o u n t e r e d , but a s t h e u r g e n c y o f t h e f l o o d p r o t e c t i o n work was s o g r e a t , t h e r e h a s b e e n l i t t l e t i m e f o r r e s e a r c h ,
I n a d d i t i o n t o t h e a c t u a l c o n s t r u c t i o n o f t h e d i k e s t h e r e h a s been t h e c o n s t r u c t i o n of pumping s t a t i o n s which k e e p t h e r i v e r o u t o f sewer o u t f a l l s , and t h e i n s t a l l a t i o n s of sewage pumps. F o o t i n g s o f t h e s e purnping s t a t i o n s a r e between 3 5 and 4 0
f e e t below t h e s u r f a c e of t h e g r o u n d , S o i l c o n d i t i o n s v a r y from c l a y and s a t u r a t e d s i l t t o s a n d which becomes "quick1' upon
e x c a v a t i o n . I n a l l , 21 s t a t i o n s were c o n s t r u c t e d l a s t w i n t e r A p p r o x i m a t e l y h a l f o f t h e s e were o f t h e u s u a l r e c t a n g u l a r d e s i g n , The o t h e r h a l f u s e d c i r c u l a r m e t a l t u n n e l l i n e r s a s t.he o u t s i d e forms f o r t h e c o n c r e t e w a l l s ,
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of B u i l d i n g Hesearch,, N a t i o n a l R e s e a r c h---
C o u n c i l --- of Canada, Ottawa (idembers l i s t e d i n Appendix)F , L , P e c k o v e r , " ~ i k e s and P o l d e r s of t h e
h ether lands",
DBH & o , 18, N a t i o n a l R e s e a r c h Council. of Canada, Ottawa, August, 1 9 5 0 >T h i s n o n - t e c h n i c a l p a p e r d e s c r i b e s t h e g e o l o g i c a l background, h i s t o r i c a l development and p r e s e n t a d m i n i s t r a t i o n
o f t h e L)ut.ch dfkini< s y s t e m , Design f a c t o r s , c o n s t r u c t i o n and x a i n t e n a n c e p r o c e d u r e s , and r e c o n s t r u c t i o n methods a r e b s i e f l y r e v i e w e d .
Department o f P u b l i c Worlrs, Prav i n c e o f A l b e r t a , lidmont on
(Mr i3.J. i j o l l i n g s h e a d )
During t h e y e a r , a number of s l i d e s d e v e l o p e d o n new
highway c o n s t r u c t i o n p r o j e c t s o V a r i o u s means of s t a b i l i - z i n g t h e s e were a t t e m p t e d , i n c l u d i n g t h e u s e of b i n t y p e r e t a i n i n g w a l l s and t h e d r i v i n g o f l i n e s of p i l e s i n t o t h e s l i a e , N e i t h e r
o f t h e s e e x p e d i e n t s was f o u n d t o be w o r t h wrlile i n i t s e l f , More s u c c e s s f u l r e s u l t s were o b t a i n e d by p l a c i n g t o e l o a d s on t h e s l i d e s and i n s t a l l i n g p e r f o r a t e d p i p e d r a i n s where t h e r e was e v i d e n c e o f f r e e w a t e r ,
U n i v e r s i t y of' Itlanitoba, Winnipeg ( P r o f , V i i J , r ' , d i d d e l l , P r o f , Oscar
-
IvIarantz, M r . Andrew B a r a c o s )
A r i v e r bank s l i d e a f f e c t i n g a p r o v i n c i a l bighway on t h e S o u r i s R i v e r i s b e i n g i n v e s t i g a t e d , The bank m a t e r i a l i s m o s t l y h e a v y b l u e c l a y , Oniy a s m a l l movement h a d o c c u r r e d when t h e i n v e s t . i g a t i o n was begun and no knowledge of t h e l o c a t i o n o f t h e s l i d i n g p l a n e was a v a i l a b l e , Two o b s e r v a t i o n t e s t h o l e s wich l i g h t c o r r u g a t e d l i n e r s were p u t down t o att.empt t o l o c a t e t h e p o s i t i o n of t h e s l i d i n g s u r f a c e , The slow s l i p h a s g i v e n no u s e f u l o r c c l n c l u s i v e i n f o r m a t i o n t o d a t e , which i n d i c a t e s t h a t
it. may be i n t e m p o r a r y e q u i l i b r i u m ,
M i n i s t e r e de l a V o i r i e
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de Que'bec, Cudbec ( D i r , Pol'vlo B i l o d e a u ) 14urnerous s m a l l l a n d s l i p s o c c u r r i n g a l o n g t h e banks o f t h e R i c h e l i e u Hiver were i n v e s t i g a t e d , B o r i n g s and t e s t a s ons o i l samples showed t h a t t h e s e s l i d e s were n o t due t o t h e s o i l b u t r a t h e r t o waves on t h e r i v e r d e v e l o p e d by p a s s i n g b o a t s
SECTION
V
E a r t h P r e s s u r e ; S t a b i l i t y and D i s p l a c e m e n t s of R e t a i n i n g C o n s t r u c t i o n s P r a i r i e Farrn d e f - l a b i l i t a t i o n A d r n i n i ~ t r a t ~ i o n , Department o f A g r i c u l t u r e-
o f Canada- S a s k a t o o n (lvlembers l i s t e d i n A ~ ~ e n d i x ) A t e s t t u n n e l h a s been d r i v e n a t t h e s i t e o f t h e p r o p o s e d e a r t h dam on t h e S o u t h Saskatchewan R i v e r t o o b t a i n e s t i m a t e s o ft h e magnitude o f l a t e r a l and v e r t i c a l p r e s s u r e s which t h e s o f t Bearpaw s h a l e w i l l e x e r t on t h e permanent l i n i n g o f t u n n e l s o r c o n d u i t s ,
The t e s t s e c t i o n of t h e t u n n e l i s l i n e d c o n t i n u o u s l y w i t h r e i n f o r c e d c o n c r e t e s l a b s on t h e s i d e s , f l o o r and r o o f , The s l a b s a r e h e l d i n p l a c e by columns t h r o u g h which l o a d s may be a p p l i e d w i t h j a c k s and t h e p r e s s u r e measured by s t r a i n r e a d i n g s , I n i t i a l l y > p r e s s u r e s e q u a l t o t h e o v e r b u r d e n p r e s s u r e were a p p l i e d h o r i z o n t a l l y t o t h e w a l l s l a b s and v e r t i c a l l y t o t h e f l o o r and r o o f s l a b s , S i n c e t h a t
a p p l i c a t i o n , measurements have been t a k e n t o o b s e r v e c h a n g e s i n t h e p r e s s u r e s , To d a t e , t h e s e have been d e c r e a s i n g g r a d u a l l y ,
w i t h a n a v e r a g e r e d u c t i o n o f 8 p e r c e n t f o r t h e h o r i z o n t a l p r e s s u r e s and 18 p e r c e n t f o r t h e v e r t i c a l p r e s s u r e s ,
F o u n d a t i o n P r e s s w e and A e t t l e m e n t s o f B u i l d i n g s
--
--- on F o o t i n g s and H a f t s-
---
D i v i s i o n of B u i l d i n g H e s e a r c h , I l a t i o n a l H e s e a r c h i o u n c i l of Canada, Ottawa (dlembers l i s t e d i n Appendix)
S t u d y of 5 u i l d i n g
settle men>^:
Along w i t h a s t u d y of socie t y p i c a l Canadian s o i l s , a d e t a i l e d s t u d y o f b u i l d i n g s e t t l e m e n t s w j t haccompanying damage i s i n p r o g r e s s , There a r e two aims i n t h i s s t u d y : t o f i n d o u t t h e r e l a t i o n s h i p between t h e p h y s i c a l p r o p e r t i e s of p a r t i c u l a r f o u n d a t i o n s o i l s , a s r e v e a l e d by L a b o r a t o r y t e s t s , and t h e a c t u a l s e t t l e m e n t s ; and t o o b s e r v e t h e amount o f s e t t n e m e n t whric2.1 v a r i o u s t y p e s o f b u i l d i n g s c a n s t a n d w i t h o u t a p p a r e n t darnage, An irnproved and s i r n p l i f i e d w a t e r t u b e l e v e l f o r d e t e r m i n i n g
d i f f e r e n t i a l s e t t l e m e n t s i n b u i l d i n g s h a s been d e v e l o p e d and i s b e i n g u s e d i n t h r e e l a r g e b u i l d i n g s i n Ottawa and T o r o n t o - Two of t h e s e b u i l d i n g s a r e founded on c l a y on c o n t i n u o u s s l a b s The t h i r d i s on wide C a n t i l e v e r f o o t i n g s , ( H e p o r t e d by h~r C , b, Csawfordl S t u d y of F l a t C o n c r e t e S l a b s on Ground: Basernentless h o u s e s on f l a t c o n c r e t e s l a b s h a v e been u s e d r e c e n t l y i n many l o c a l i t i e s i n :anada i n an a t t e m p t t o economize i n h o u s e c o n s t r u c t i o n , b u t a 3 y e t no r a t i o n a l s l a b d e s i g n h a s e v o l v e d . fin e x p e r i m e n t a l f i e l d p r o j e c t i s t h e r e f o r e being; s t a r t e d w i t h t h e i n i t i a l aim of f i n d i n g a s l a b de s i p s u i t a b l e f o r c o n s t r u c t i o n on s w e l l i n g and s h r i n k i n g c l a y s " Two r u l l - s c a l e u n r e i n f o r c e d s l a b s ape u n d e r c o n s t r u c t i o n and
a d d i t i o n a l s l a b s w i l l be e o n s t r u e t e d n e x t
summer,
Sampling andt e s t i n g of s o i l on t h e s i t e i s i n p r o g r e s s , ,
I n s t a l l a t i o n o f t h e s e s l a b s w i l l g i v e o p p o r t u n i t y f o r a v a r i e t y of s o i l s t u a i e s , Hecords w i l l be k e t of' v e r t i c a l
~tlovernent ( d e t e c t e d by ground movement d a u g e s
f'
and m o i s t u r e and t e m p e r a t u r e v a r i a t i o n of s o i l s a t v a r i o u s o e p t h s a s w e l l a s w e a t h e r c o n d i t i o n s , g r o u n d w a t e r d e p t h s , and v e r t i c a l movement o f t h e c o n c r e t e s l a b s The e f f e c t of h e a t from t h e r a d i a n t h e a t i n g s y s t e m of t h e s l a b s on s o i l t e m p e r a t u r e s and m o i s t u r e a t d e p t h w i l l a l s o be s t u d i e d , ( H e p ~ r t e d by G1rc F,La
P e c k o - ~ e r ) G n i v e r s-
i t y o f SaS k a t chewan, S a s k a t o o n ( M r , B, B o T o r c h i n s k y ) A s t u d y of b u i l d i n g movements on h i g h l y p l a s t i c c l a y s h a s been made t o a r r i v e a t some p r a c t i c a l d e s i g n methods t o e l i m i n a t e c r a c k i n g of w a l l s and jamming of d o o r s and windows, c a u s e d by d i f f e r e n t i a l s e t t l e m e n t op h e a v e of b u i l d i n g s The A e s i n a S o l l e g e Gymnasium h a s b e e n t h e m a j o r o b j e c t of s t u d y , Z t h a s s e t t l e d c o n s i d e r a b l y a l o n g t h e w e s t w a l l , c a u s i n g e x t e n s i v e c r a c k s t o open up i n t h e i n t e r i o r p a r t i t i o n s ,, S t u d i e s h a v e shown t h a t t h e r e a s o n f o r t h e s e t t l e m e n t i s t h e d r y i n g o u t and c o n s e q u e n t volume d e c r e a s e o f t h e h i g h l y p l a s t i c c l a y on which t h e f o o t i n g s r e s t , During l a s t s u m e r , a u g e r h o l e s were made a l o n g t h i s w a l la n d w a t e r was added t o t h e h o l e s f o r a p e r i o d of s e v e r a l weeks, As a r e s u l t , t h e c l a y s w e l l e d s u f f i c ' l e n t l y t o r a i s e t h e w a l l a d i s t a n c e of o v e r one i n c h . A s e c o n d b u i l d i n g , of s i m i l a r b u t more r e c e n t c o n s t r u c t i o n , h a s been u n d e r o b s e r v a t i o n i n t h e same a r e a , It i s b e g i n n i n g t o d e v e l o p c r a c k s a l o n g t h e w e s t w a l l . I n t h i s c a s e t h e m o i s t u r e d e f i c i e n c y r e s p o n s i b l e f o r t h e damage may be c a u s e d by v e g e t a t i o n , S e t t l e m e n t p l u g s have been i n s t a l l e d i n t h i s and s e v e r a l o t h e r s t r u c t u r e s s o t h a t b u i l d i n g movements may be a n a l y s e d , T h i s work h a s b e e n done by a g r a d u a t e s t u d e n t and f i n a n c e d by a g r a n t from t h e Saskatchewan H e s e a r c h C o u n c i l . H y d r o - E l e c t r i c Power Commission o f O n t a r i o , T o r o n t o ( M r ,
D.G.
' i i a t t , M r ,W,
Trow) A s t u d y h a s b e e n made t o d e t e r m i n e methods f o r e l i m i n a t i n g f r o s t h e a v i n g of s m a l l f o o t i n g s , T h i s phenomenon h a s c a u s e d c o n s i d e r a b l e t r o u b l e i n t r a n s f o r m e r y a r d s and o t h e ra r e a s where s m a l l f o o t i n g s a r e employed, The i n v e s t i g a t i o n s s u g g e s t t h a t t h e f o o t i n g s s h o u l d be c o a t e d w i t h low t e m p e r a t u r e g r e a s e o r s h o u l d be b a c k f i l l e d w i t h v e r y l o o s e s o i l , I t i s
p l a n n e d t o t e s t t h e s e methods i n t h e f i e l d on f o o t i n g s w i t h a bad f r o s t h e a v i n g r e c o r d , ;
SXCTlON V I I I
Problems of Hoad and Runway C o n s t r u c t i o n
-
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D r , Norman W, McLeod, Department o f A s p h a l t Technology, I m p e r i a l O i l L i m i t e d , ~ 6 r o r l t o
Norman
W,
IvlcLeod, 'liiconomical F l e x i b l e Pavement D e s i g n Developed from Canadian Runway S t u d y " E n g i n e e r i n g News-Record, A p r i l 28, May 1 2 , Lay 2 6 , J u n e 9, 1946.T h i s s e r i e s of a r t i c l e s p r e s e n t s some of t h e more i m p o r t a n t r e s u l t s of a s t u d y of t h e d e s i g n , p e r f o r m a n c e , and
e v a l u a t i o n of a number o f Canadian a i r p o r t s t h a t i s b e i n g c a r r i e d o u t by t h e Department of T r a n s p o r t o f C a n a d a ,
Norman
W,
blcleod, "Pavement Design iViethods ~ e f ended1', E n g i n e e r i n g idews-Hecord, hlebruary 23, 1 9 5 0 ,A r e p l y t o a d i s c u s s i o n o f t h e above s e r i e s o f a r t i c l e s by P e t e r
B.
Hyzer t h a t was p u b l i s h e d i n E n g i n e e r i n g News-hecord, November 1 7 , 1 9 4 9 ,Norman
W.
McLeod, "The R a t i o n a l D e s i g n o f Bituminous Pavingb l i x t u r e s l ' , P r o c e e d i n g s , Ilighway R e s e a r c h Board, Vol, 29, December, 1 9 4 9 ,
Norman
W,
McLeod, "A R a t i o n a l Approach t o t h e Design o f Bituminous Paving I / l i x t u r e s " , P r o c e e d i n g s , t h e A s s o c i a t i o n o f A s p h a l t Paving T e c h n o l o g i s t s , Vol 1 9 , F e b r u a r y , 1 9 5 0 "Worman l V o IiicLeod, " A p p l i c a t i o n of T r i a x i a l T e s t i n g t o t h e D e s i g n of Bituminous Pavernent s " , Symposium on T e s t i n g S o i l s Under
T r i a x i a l Loading, American S o c i e t y f o r T e s t i n g M a t e r i a l s : J u n e , 1 9 5 0 -
These t h r e e p a p e r s d e s c r i b e a method f o r d e s i g n i n g t h e s t r e n g t h o r s t a b i l i t y of b i t u m i n o u s m i x t u r e s i n t e r m s of pounds p e r s q u a r e i n c h , b a s e d on t h e u s e of t h e t r i a x i a l t e s t . and Mohr d i a g r a m , A method f o r c a l c u l a t i n g t h e amount of l a t e r a l s u p p o r t p r o v i d e d by t h e pavement m a t e r i a l a d j a c e n t t o t h e l o a d e d a r e a s i s i n c l u d e d , The i n f l u e n c e o f t h e v i s c o u s
r e s i s t a n c e of b i t u m i n o u s m i x t u r e s on t h e i r s t a b i l i t y i s d e s c r i b e d , The e f f e c t of t h e f r i c t i o n a l r e s i s t a n c e between pavement and
t i r e and between pavement and b a s e on t h e s t a b i l i t y of b i t u m i n o u s pavements i s i n v e s t i g a t e d , The i n f l u e n c e o f t h e s h a p e o f t h e c u r v e of p r e s s u r e d i s t r i b u t i o n o v e r t h e c o n t a c t a r e a , and o f pavement t h i c k n e s s on pavement s t a b i l i t y , i s d i s c u s s e d , The e f f e c t of s t a n d i n g and moving wheel l o a d s and of b r a k i n g s t r e s s e s on t h e d e s i g n of b i t u m i n o u s m i x t u r e s i s c o n s i d e r e d ,
Norman
VJ,
IdcLeod,h he
D e s i g n o f F l e x i b l e ~ a v e m e n t s " , P r o c e e d i n g s , New York S t a t e A s s o c i a t i o n o f Highway E n g i n e e r s , Iilarch,, 1 9 5 0 ,Norman
W,
IvlcLeod, A d i s c u s s i o n of t h e p a p e r by C , A , C a r p e n t e r ,J . F, Goode, and
H ,
A , Peck on ''An Improved T r i a x i a l C e l l f o r T e s t i n g Biturninous Paving l ~ i i x t u r e s " , P r o c e e d i n g s , The A s s o c i a t i o n o f A s p h a l t Paving ' T e c h n o l o g i s t s , , V o l , 2 0 , 1 9 5 1 ,It i s p o i n t e d out t h a t t h e c e l l t r i a x i a l a p p a r a t u s h a s a p p a r e n t l y been used v e r y s a t i s f a c t o r i l y f o r d e t e r m i n i n g t h e v a l u e s of c and
$d
f o r bituminous m i x t u r e s , a s w e l l a s t h e open t y p e o ftr i a x i a l a p p a r a t u s d e s c r i b e d by t h e a u t h o r s , In addit. i o n , t h e
d i s c u s s i o n e x p l a i n s why t h e u n c o n f i n e d compression t e s t i s b e l i e v e d t o be e n t i r e l y u n s a t i s f a c t o r y f o r d e s i g n i n g bituminous paving
m i x t u r e s from t h e s t a n d p o i n t of t h e i r s t a b i l i t y n
Norman
W,
McLeod, A d i s c u s s i o n of a paper by P r o f e s s o rW,
H,
Goetz on " ~ o r n ~ a r i s o n of T r i a x i a l and M a r s h a l l T e s t r i e s u l t s " , P r o c e e d i n g s , The A s s o c i a t i o n of A s p h a l t Paving T e c h n o l o g i s t s , Val- 20, 1951,I n t h f s d i s c u s s i o n , a somewhat d i f f e r e n t i n t e r p r e t a t i o n of t h e d a t a c o n t a i n e d i n t h e paper i s g i v e n t h a n t h a t a r r i v e d a t by t h e a u t h o r , It i s p o i n t e d o u t t h a t on t h e b a s i s of van J . t e r s o n y s t h e o r y , t h e Mohr c i r c l e f o r t h e M a r s h a l l s t a b i l i t y t e s t s h o u l d be i d e n t i c a l , o r v e r y n e a r l y s o , w i t h t h e Mohr c i r c l e r e p r e s e n t i n g uncorlfined cornressive s t r e n g t h . Prom t h e c and
9
v a l u e s o b t a i n e d ,a method i s d e s c r i b e d whereby a g r a p h of t r i a x i a l s t a b i l i t y v e r s u s a s p h a l t c o n t e n t may be madeo I t i s demonstrated t h a t P r o f e s s o r 30etZ d a t a i n d i c a t e a L i n e a r r e l a t i o n s h i p between v a l u e s of t h e " f l o w index" measured f o r bituminous m i x t u r e s by t h e IVlarshall t e s t = v e r s u s v a l u e s of t h e a n g l e of i n t e r n a l f r i c t i o n
$d,
measured f o r t h esame m i x t u r e s by t h e t r i a x i a l t e s t , The d i s c u s s i o n i s i n t e n d e d t o show t h a t t h e M a r s h a l l t e s t i s n o t s a t i s f a c t o r y f o i measuring t h e s t a b i l i t y or" bituminous paving m i x t u r e s , because it would r e j e c t a s being u n s t a b l e , paving m i x t u r e s t h a t would develop more t h a n adequate s t a b i l i t y i n t h e f i e l d , Unless t h e Slow i n d e x p r o v i d a s an adequate check, it i s p o i n t e d o u t t h a t t h e lvlarshall t e s t would a l s o accept a s e n t i r e l y s a t i s f a c t o r y , paving m i x t u r e s t h a t would be q u i t e u n s t a b l e i n t h e f i e l d ,
Department of ilighwags of the-Province of O n t a r i o Y
( M r , John W a l t e r )
Toronto
Subgrade Bearing C a p a c i t y : The program of i n v e s t i g a t i o n of t h e b e a r i n g c a p a c i t y of subgrades and base c o u r s e s i n i t i a t e d i n 1948 has been c o n t i n u e d , Within t h e l a s t y e a r t h e program h a s been d i r e c t e d mainly a t d e t e r m i n i n s t h e s e a s o n a l v a r i a t . i o n of t h e
b e a r i n g c a p a c i t i e s of b a s e c o u r s e s and s u b g r a d e s A 2 0 - t o n l o a d e d t r a i l e r i s used t o p r o v i d e t h e l o a d t h r o u g h a h y d r a u l i c j a c k , i t
i s hoped u l t i m a t e l y t o use t h e c o l l e c t e d d a t a a s a b a s i s f o r b a s e c o u r s e and pavement d e s i g n ,
Simpler and l e s s expensive t e s t s such a s cone b e a r i n g , and C a l i f o r n i a b e a r i n g r a t i o t e s t s a r e performed on t h e subgrade f o r c o r r e l a t i o n w i t h p l a t e b e a r i n g t e s t s . To d a t e t h i s c o r r e l a t i o n h a s n o t been e n c o u r a g i n g "
The i n d i c a t i o n s t o d a t e a r e t h a t t h e subgrade l o s s i n b e a r i n g c a p a c i t y w i t h s p r i n g break-up does not c o r r e l a t e w i t h m o i s t u r e c o n t e n t of t h e s u b g r a d e o This seems t o a g r e e w i t h t h e f i n d i n g s of o t h e r r e s e a r c h g r o u p s ,
Subgrade T e m p e r a t u r e s and F r o s t Heave: I n o r d e r t o s t u d y s u b g r a d e t e m p e r a t u r e v a r i a t i o n , f o u r i n s t a l l a t i o n s were made t o i n c l u d e sand and p l a s t i c s o i l s i n c u t and f i l l s e c t i o n s , The i n s t a l l a t i o n s g i v e r e a d i n g s from d e p t h s of 6 i n c h e s t o 6 f e e t , R e a d i n g s a r e t a k e n w e e k l y , A c o m p l e t e a n n u a l c y c l e h a s n o t y e t been c o v e r e d , s o no c o n c l u s i o n s a r e drawn, P r e c i s e l e v e l s a r e b e i n g t a k e n a t 1 8 s i t e s on r e c e n t l y c o n s t r u c t e d s e c t i o n s o f highway, These s h o u l d i n d i c a t e w h e t h e r f r o s t h e a v i n g i s t a k i n g p l a c e i n s o i l s which a r e c u r r e n t l y a c c e p t e d a s s u i t a b l e i n s u b g r a d e s , L a b o r a t o r y f r o s t h e a v i n g i n v e s t i g a t i o n s a r e b e i n g made on s o i l s r a n g i n g from f i n e s a n d t o s i l t s and h e a v y c l a y s , Samples a r e b e i n g f r o z e n u n d e r a r a n g e o f s u r c h a r g e w e i g h t s t o d e t e r m i n e w h e t h e r s o i l s might h e a v e a t t h e s u r f a c e b u t be a c c e p t a b l e a t some d e p t h i n t h e s u b e r a d e w i t h i n t h e d e p t h of f r o s t p e n e t r a t i o n .
U n i v e r s i t y
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o f A l b e r t a , Edmonton (Dean R,i:u'll. Hardy, Nir. S , H . ~ i n c l a i r ) R o b e r tM,
Hardy, " C o n s t r u c t i o n Problems i n S i l t yoils",
TheE n ~ i n e e r i n g .. J o u r n a l , September 1 9 5 0 ,
T h i s p a p e r d e a l s w i t h highway and a i r p o r t f l e x i b l e pavement f a i l u r e s on s i l t y s u b s o i l s , It a l s o d e a l s w i t h c o n s t r u c t i o n problems e n c o u n t e r e d i n l o e s s d e p o s i t s o c c u r r i n g i n c e n t r a l B r i t i s h Columbia, R o b e r t lV1, Hardy and P. J , R i v a r d , " S t r e s s D i s t r i b u t i o n Below Pavements Under T r o l l e y d u s Loadingst1, P r o c e e d i n g s , Highway R e s e a r c h Yoard, Volume 30, 1 9 5 1 ,
T h i s p a p e r r e p o r t s t h e r e s u l t s of a n i n v e s t i g a t i o n made i n t h e C i t y o f Edmonton a t t r o l l e y bus s t o p p o i n t s , P r e s s u r e c e l l s were p l a c e d below b o t h r i g i d and f l e x i b l e t y p e s o f pavement and a
comprehensive s e r i e s o f s t r e s s measurements were s e c u r e d , The
e f f e c t s o f b r a k i n g and a c c e l e r a t i o n f o r c e s were a s s e s s e d and i t was c o n c l u d e d t h a t t h e s e were o f minor i m p o r t a n c e . The t r o u b l e
e n c o u n t e r e d a t t r o l l e y bus l o c a t i o n s i n t h i s a r e a where t h e s u b s o i l i s c l a y i s r e p o r t e d t o b e due t o i n s u f f i c i e n t t h i c k n e s s o f pavement and b a s e c o u r s e t o p r e v e n t breakdown o f t h e s u b s o i l c l a y u n d e r t h e l a r g e number of r e p e t i t i o n s of l o a d r e s u l t i n g from s u c h t r a f f i c -.
Improvement
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of t h e Mechanical P r o p e r t i e s of S o i lDepartment
- of Highways --. and T r a n s p o r t a t i o n o f P r o v i n c e o f Saskatchewan,
Regina ( M r , W , S , W i n n i t o y )
During t h e p a s t few y e a r s d a t a h a v e been a s s e m b l e d t o e s t a b l i s h a r e l a t i o n s h i p between optimum m o i s t u r e and rnaximmn
s t a n d a r d P r o c t o r d e n s i t y f o r Saskatchewan s o i l s ,, Such a r e l a t i o n s h i p h a s now b e e n s u c c e s s f u l l y e s t a b l i s h e d f o r t h e s e s o i l s , arid a g r a p h i s a v a i l a b l e t o show t h i s r e l a t i o n s h i p . It i s hoped t o e x t e n d t h e c u r v e i n t i m e t o i n c l u d e maximum d e n s i t i e s of s o i l s t a b i l i z e d g r a v e l b a s e c o u r s e s , The g r a p h i s o f
rea at
a s s i s t a n c e i n c h e c k i n g r e s i ~ i t s o b t a i n e d when doing a s t a n d a r d P r o c t o r d e n g i t y t e s t on f i e l d s o i l s , I n d o i n s s o , much t i m e i s s a v e d by a v o i d i i l g d u p l i c a t e t e s s r!msU n i v e r s i t y of A l b e r t a Edmonton (Dean
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9 H,i\il. l a r d y , lVk, S.R,
~ i n c l a ~ r ) F i e l d-. Compaction P r o c e d u r e s : Work was c o n d u c t e d on a c o - o p e r a t i v e program, f i n a n c e d j o i n t l y b y t h e A l b e r t a R e s e a r c h C o u n c i i , , t h e
~ a t i o n a ' i R e s e a r c h ~ o u n c i i of Canada, and r o a d b u i l d e r s
'
o r g a n i z a t f o m , i n which f i e l d c o m p a c t i o n p r o c e d u r e s and r e s u l t s were s t u d i e d ,I n t e r e s t i n g f i e l d m o i s t u r e - d e n s i t y r e l a t i o n s have b e e n s e c u r e d . Use o f L i g n o s o l t o fieduce F r o s t Heaving: L a b o r a t o r y t e s t s i n 1916
--
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c o n c l u s i v e l y d e m o n s t r a t e d t h a t i c e s e g r e g a t i o n i n s o i l s h i g h l y s u s c e p t i b l e t o f r o s t a c t i o n c o u l d be e f f e c t i v e l y p r e v e n t e d by t h e a d d i t i o n of a b o u t 4 p e r c e n t of l i g n o s o l , T h i s c h e m i c a l i s m a n u f a c t u r e d from l i g n i n ( o r s u l p h i t e l i q u o r ) which i s a w a s t e p r o d u c t of t h e p a p e r m a n u f a c t u r i n g i n d u s t r y " During t h e w i n t e r c f 1950-51, t h r e e l o c a t i o n s i n which f r o s t t r o u b l e had b e e n r e g u l a r l y e n c o u n t e r e d on one of t h e Canadian r a i l w a y l i n e s were t r e a t e d w i t h l i g n o s o l , i n a d d i t i o n , a n a r e a i n a c u r l i n g r i n k u s i n g a r t i f i c i a li c e was t r e a t e d , The p u r p o s e s o f t h e f i e l d t e s t s were f i r s t , t o d e v e l o p a s a t i s f a c t o r y t e c h n i q u e f o r t h e i n j e c t i o n of t h e l i g n o s o l ; s e c o n d , t o s e c u r e d a t a on t h e r a t e a t which t h e c h e m i c a l i s l e a c h e d o u t i n t o t h e z r o u n d w a t e r ; and t h i r d , t o a c q u i r e c o s t d a t a on s u c h f i e l d
treatments
,The problem of i n j e c t i o n of t h e l i g n o s o l p r o v e d somewhat d i f f i c u l t , b u t was f a i r l y e f f e c t i v e l y s o l v e d u s i n g p o r t a b l e
equipment which was c a p a b l e of p ~ p i n g u n d e r a p r e s s w e o f about. 30 pounds p e r s q u a r e i n c h , ) , T e n t a t i v e l y , i t a p p e a r s t h a t it i s q u i t e f e a s i b l e t o p r e v e n t t h e development o f f r o s t heavi.ng and. f r o s t
b o i l s by s u c h a t r e a t m e n t and a t a c o s t t h a t would make t h e p r o c e s s e c o n o m i c a l l y p r a c t i c a l u n d e r emergency cond jt i o n s a t l e a s t
.
The r a t e of d i s s i p a t i o n of t h e l i g n o s o l i n t h e g r o u n d i s n o t y e t known,E c o l e Pol-ytechnigue, M o n t r e a l ( P r o f , J,ii, H u r t u b i s e ) Use
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of L i g n o s o l t o kteduce F r o s t Heaving: F o l l o w i n g some e x p e r i m e n t s c a r r i e d o u t by Dean H .IM, Hardy of t h e U n i v e r s i t y o f A l b e r t a which showed t h a t t h e a d d i t i o n of l i g n o s o l would p r e v e n t i c e s e g r e g a t . i o n , a p a r t i c u l a r l y bad f r o s t h e a v i n g s e c t i o n of a highway i n n o r t h e r n ~ u e b e c was e x p e r i m e n t a l l y t r e a t e d w i t h .Lignosol, The s o l u t i o n wasi n j e c t e d i n a shiallow l a y e r o f t h e s i l t y s u b s o i l , The q u a n t i t y o f l i q u o r u s e d f o r t h e t r e a t m e n t was about 1 t o l, 5 p e r c e n t by w e i g h t of t h e s o i l s o l i d s , O b s e r v a t i o n s have i n d i c a t e d a r e d u c t i ~ n i n
h e a v i n g of a b o u t 50 p e r c e n t and it i s b e l i e v e d t h a t more l i e n o s o l s h o u l d have b e e n u s e d Some f i e l d d i f ' f i c u l t i e s were e n c c u n t e r e d b u t e x p e r i m e n t s w i l l be r e p e a t e d ,
Use of i i g n o s o l i n S t a b i l i z a t i o n : L a b o r a t o r y e x p e r i m e n t s c a r r i e d o u t s i q y e a r s ago showed t h a t t h e a d d i t i o n o f 2 p e r cent, o f a n e u t r a l i z e d s o l u t i o n o f l i g n o s o l more t h a n d o u b l e d t h e u n c o n f i n e d
c o m p r e s s i v e s t r e n g t h of a w e l l g r a d e d g r a v e l a t v a r i o u s m o i s t u r e c o n t e n t s up t o 5 . 5 p e r c e n t , It was f o u n d a l s o t h a t t h e a b s o r p t i o n of w ~ t e r by c a p i l l a r i t y was n o t i c e a b l y d e c r e a s e d when t h e g r a v e l was t r e a t e d , a s l o n g a s t h e i n i t i a l m o i s t u r e c o n t e n t was below 2 p e r c e n t ; w i t h d r y t r e a t e d g r a v e l t h e p e r c e n t a g e o f a b s o r p t i c n was approximat.ely a f i f t h of t h e u n t r e a t e d g r a v e l , F o l l o w i n g t h e s e l a b o r a t o r y e x p e r i m e n t s , many m i l e s o f r o a d s have been t r e a t e d e a c h y e a r w i t h l i g n o s o l w i t h good r e s u l t s ; o b s e r v a t i o n s a r e s t i l l b e i n g made a s t o i t s e f f e c t , A g r a v e l b a s e c o u r s e was s t a b i l i z e d p r i o r t o p a v i n g w i t h b i t u m i n o u s c o n c r e t e , t h e i n c r e a s e i n b e a r i n g c a p a c i t y of t h e g r a v e l a l l o w i n g a r e d u c t i o n i n t h i c k n e s s o f p a v i n g m a t e r i a l . It i s b e l i e v e d a l a o t h a t t h e a d d i t i o n o f l i g n o s a l r e d u c e d t o some e x t e n t t h e d e s t r u c t i v e a c t i o n of f r o s t , Paving o p e r a t i o n s were f o u n d t o be g r e a t l y f a c i l i t a t e d u n d e r t r a f f i c c o n d i t i o n s -.
