Construction and maintenance of road over peat

Publisher’s version / Version de l'éditeur:

Technical Memorandum (National Research Council of Canada. Associate Committee on Soil and Snow Mechanics), 1954-07

READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. https://nrc-publications.canada.ca/eng/copyright

Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la

première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca.

Questions? Contact the NRC Publications Archive team at

PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information.

NRC Publications Archive

Archives des publications du CNRC

For the publisher’s version, please access the DOI link below./ Pour consulter la version de l’éditeur, utilisez le lien DOI ci-dessous.

https://doi.org/10.4224/40000390

Access and use of this website and the material on it are subject to the Terms and Conditions set forth at Construction and maintenance of road over peat

Dryburgh, F. B.; Mckillop, E. R.

https://publications-cnrc.canada.ca/fra/droits

L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.

NRC Publications Record / Notice d'Archives des publications de CNRC: https://nrc-publications.canada.ca/eng/view/object/?id=e4d54fb4-673f-4733-8877-c3182feaf691 https://publications-cnrc.canada.ca/fra/voir/objet/?id=e4d54fb4-673f-4733-8877-c3182feaf691

T E C H I T I S A L bEP!OFiANllUl~I NO. 29 C O N S T R U C T I C N

AND

M A I N T E l g A N C E O F ROADS OVER P E A T ,,-...---.--- -I--- ----.".-.-- I-

.--.-

I

---

----.

'3

i 1 q A T I O N A L R E S E A R C H C O U l i C I L t _{2 AN.4DA}

'

I

! _{i i S t S O C I A . T E C 0 W ; I I T T E E O N SOIL AID SNOW M E C X A N I C S}

I

I

!

I

f

!

I

i I i

i

!

i

i

I i I

I

I I

I

I

I

I

I

I

I

1

I

I

I

I i

i

a

i

I

I

s i

f

!

I

!

I B

i

i I

!

!

Ottarva J u l y

1954

₁ _ _ _ . - I-..-_-l__.,--I.--CLIII

.--..,--

-. -.-.. - .

-

F,

B.

Drybui2gll and X,H, McKiPlop

~ ~ j - . : i , ~ t >., ,L,ec?.

-

-~,i",t"h t h 6 k h i d p e ~ m f ssion o f t h e

Ii!.:i?d 3r?cea:.zh L.3bc.rat;c.ry, De7artrnen.l; o f

.I T

~ ; ' l . , ~ ~ : f i c . and T ~ , d ' ~ . 3 . k , ~ < a , d s s e & i - c h 3 G r e a t

PREFACE

--->~==..-

One c f t h e prime r e s p c n s f b 9 ' l i t i e s o f " t 3

i i s ~ c ~ f s t e Connf't;-Les ~?r, Soil and Snow Mechanics Sa t h e p r c s e c g t i cr! and devsicpment o f r e a e a p ~ ~ h work on muskeg,

v i a w of t h e ~ f d e s p r ~ a d 2X.~trS.~;i'r_lcan o f muskeg f n the

n o ~ t k c::f Canada and 19 it3 g ~ e a t f m p o ~ t a n c e to Canadian 5cosr.-mic dsveloy.~rnsnt. The Assoc"ra.be Ccmmlttee f c u n d

f;.., .> " .f.h3rti .d -i,Y*-7-7

> - - a $ .

-

j i f t t 1 a i~!.l.f::~rilaSf or, available 3 2

s l r t Jsc;?: ::of" m : ~ s k s g o r upon the e n g f n e e r f n g a s p e s t s o f Feat deposits wklf , h p r o v i d e s 5 r n i l a ~ t e ~ r a f n ccinditicna

i n o t h e ? ~ r ; i ~ - t ~ I ~ ~ ~ ,

P L z n l j s . ~ wcrk i n t h e i n v e s t i g a t i o n

cr

muskeg

lias ncu been d c n e b y D F * N o

W,

Radf'c-th c.f McMavter U n i v s r e f t y , H a n i l t o n , w i t h t h e s u p p s ~ t of %he A s s o c i a t e

C ~ o i m i , L & e a , H i s work i s bsing continued and f u ~ t h e r

de-deloped, as p * ~ b l i c . a t f c n a

of"

t h a A s s o c f a t e Ccimmitt.5e?

denonstpats. T h l s p u b 1 i c a t i c n cf' t h s Cornnf t t . e e i s , h ~ w 9 - i ~ ~ ~ ~

qt;j.i;e drf~"e.;a;lt j.r, . ~ h a ~ c 7 c t ~ , 2 r . ,

I

t 3- ,an

-

n o t dea; w i t h

Ganaaian .cju;.I: b 2 t i s R i-eprfnt f"rc,!-;r a p r i v a t e B r i t t s t - n

ptiblfca$:on, 11: i s ~ e p ~ l ~ d t ~ : , j d k n t h i s s e r i e s b y k3nd

perm:s.~i.i,;r: of' Dpe W,B. G l a n : r f l l e , D f r e c t o r of" ;;he B r T t i ~ h

R c s 6 Ra;:.eii-'.:in L&bi:ratory c F t h e D e p a ~ t a e n ? col" S c i e n t i f L a

ezLd Irsrj;l:s+,= Rajaapch,

k d e i - the a u s p f c e a o f the a r f t f s h Road R e s e a r c h

L a b s r a t c r y a Ccrflerence was h e l d a"; I n v e r n e s s , S ~ o t P a n d l , ~

i n ~ v j

-,,

~ . - < . . ~ h

...-

l95:5 i n c r a s r t.12 .::-.r~sfder t h e d e s l g r , and c o n s t r u c t l ~ : s n o f r a g 5 3 fa N o r t h e ~ r - Sc.e;Par).d, A r e c o r 4 of' t h l s w ~ e e t f r , ~ w s a p l - e p a ~ e c ! find a ,c.;y WF:? .rae:aS-ved. t;y th.3 N O R O C , D i v l l s ~ c , n o f

B u i l dffig R~~-raealac:h,

It.

w a z fc~1nd tohat kb.e r e c o ~ d c o n t a i n e d a efngu-2

1 a r l g in+,eresti;r.g . ' ~ 4 i j ; . f : 5 ~ .:..la 5hs ~ C D ~ ~ ~ I . . U S C ~ O ~ knd main te%i.ancc:

of' zvr~ada cvi.er p 5 a';,, Sirrc; +c nj1ic.h of the i d ~ ~ c m ~ ~ ; % L ? i ~ 2.~1)e a*~.'?z

r a l a v a n t tc oc.:?rcipandi.ng Gmaiz:i&n p r o b l e m s w9't;h mia-+keg a r d

s i m a t h s r - s li. s o Lf-it,::~ i n fir,gir,aering ~ l % m s & u r e cn this ;:-12.b jezt;, a ~ l t h c r i - k g w&:j e ~ P l r : . : L t e d rer t h e r e p r o d u e t i c n of t h i s p a r t cf t h e r e c ~ r d a f t,lls Invrsmess Gonfeaencs, W f t h Di-, G I a r . v f l l e s k:r,cl p : j r ; r r , i ~ a i o n t h e A s s a c l a t e Co.~=;miQtee now lim p i e a c u p e :n making t k 1 i . 3 inr'crmatlon s v a f l a b l e Tor

u : ~ t h ~ c u . g h c ~t Canada, Ccri~.~erit;& or, t h i s p a p e r and s a g g e s t f cns

fi,r f ur?..har r ( ~ : s a:,ch ~ c - r k in cc:rAn'5et.hon wi.th musk'sg w Z P 1 be g r e z t l y a?prr.e:.lakad. ~ i i d n3y h e sent ?'o t h e u r , d a r s ' i { ~ ~ ~ . s 1,

O t t a w a ,

CONSTRUCTION AND MAINTENANCE OF ROADS OVER PEAT -P--L---- -I n ~ r s d ~ e e d by F O B o Dryburah, M,I,Mun.E.,

----

a

-

--

Gount,v S v . ~ u s v o r o f S h e t l a n d and M r , F O E , D ~ ~ ~s a f d t h a t ~ ; ~ h i s & t a l k ~ e f e ~ y s e d t o ths

----

co:13frui:sfon ~ f 1wt~-.~r=s'E: 1road.a over p e a t t o caysysy l i g h t t i n a f f f c for. +;awnship schsmes: o r f c r tempclnaalry a c c e s s r o a d s f o p c r v i l

e n g i n e e r i n g pr:e 3 9 c c s a The p a a t r e f e ~ ~ e d t o f s h S l l p e a t which

I s t h e t y p e generai1.g enz,ountarad a l l o v e r t h e Hilghlands and

I s l a n d s , H f l l p e a t i s f i,bn"ous t h a t a p of t h e d e p o s i t b u t c o l l o i d a l i n nat?zre i n f . t s lower l a y e r s , I n I t s n a t u r a l s t a t e , t h e w a t e r c o n t e n t of peat s x r e ~ a g e a 90-95 p e r c a n t , i t s s h e a r s t r s r i t h i s very l o w i i and iCs bsasafng c a p a c i t y may be t a k e n a s almus t n i l . The f 2 r a t c o n s l d e r a t i s n i s , - ~ h s r e f o r e , t o I n e r e a s e

i t s s h e a r streng'iih and b3ar:cg c a p a c i t y , Thfs c a n be done by r e d u c i n g t h e w a t e r c o ~ ~ e n t . I 0 5 , by d r a i n a g e , D r a i n a g e I s t h u s

t h e f i r s t e s ~ e r ~ t i a ' j ! and ahoulcl be completed b e f o r e any o t h s p c o n s t r u c t i i ; l n a l src-r-% 6dsc;ljef system ,shsuPd b e d e c l d e d upon and e x e c u t e d p r s f . ~ ~ ~ b X j by a m e z h a n i s a l ditehela ( a s p e c i a l t y p e

is a v a i l a b l e uhi;.h h a s a low bca~!.ng p r e s s u r e ) o r by hand l a b o u r . Drainage r s d i i > e s 5Ce water c o n t e n t by 7-10 p e r c e n t ,

i n c r e a s e s t h e shew s;seng%h by a b o u t 40 t f m e s and r a i s s s t h e b s a r i n g c a p a c i t y t o a p p ~ c r x i m a t e l y 500 I b , p e r sq, f t o

I n any consi;-..u~tie;lr;r o v e r eat, It, f a f m p a ~ t a n t t o alrm a t h a v i n g 'mifr:rr:,%ty bboth f n t h e d e s i g n of" t h e r o a d , a d i n t h e waber c c n t e n t ;"he p e a t , If t h e w a t e r c o n t e n t ~f t h e p e a t l s

m a i n t a i n e d a t a u ~ i f a r m - ~ a l l u e m o v t n e n t s dus t o volume changes a r e kept, ai; a m:inimi~s~ :;lyCI %.he s h e a r s t . ~ e n g t h w f l l a l s o 'be

restaafiably , m l f ort-1 ..thus lind~s2c.g g g r ~ a r a l l y s t a b l e @ s n d i t i o n s , When p e a t is a i r d r i s d , a s i $ i 3 f'o r f u e l , i t s .water c o n t e n t is

r e d u c e d t o 35-40 p s r c e n t an& a 00 p e r c e n t volume c h a n g s t a k e s p l a c e . I n o ~ d s r . t~ p r e v e c t a9r~.:.as move.nsnC,s s o c u r r i n g , I t is

tkierefcr-e e a s e n t f a l t o a t t e p t ;+,, > o n t r o l t h e d e g r e e of a i ~

d r y i n g of t h e p e a t n e a p and ~ndsma the r c l a d and t o m a f n t a f n k t a t a s uniform a wa';er c s n t e r - t a s P f 3 ~ 8 i b 1 9 . F i g u r e 11 shows a methad o f d a l n g this u s s d i : ~ Shatvlsnci by means of a s y s t e m s f d o u b l e d r a i n a g e d i t e h t i ~ , , They w e e f f e c t f v e i n m a i n t a i n i n g a r e a s o n a b l y u n i f o r m w a t e r c o n t s a t e x i . ~ p ~ s i n f:c?ndItfons s f d ~ ~ u g h t , which ar.8 r a r e i n t h e C r o f t e r C ~ L L V L Z B S B . T h e sec.%ion i l l u s t p a t e d i n F i g o 11 i s t y p f c a l for. a re:! a d i n .;dihit:k~ ths f ~ r m a k l e n f a P l s u f t h f n the

p e a t l a y e r , I t h a s a 'iU

f ~ s . ~

r ~ , i d s c a ~ r f a g e w a y w i t h

3

f t , wide m a r g i n s , The p e a t i s exca.wated by hand t c f o r m a t i o n , a h e a + h s r m a t t r e s s o f

18"

w

let'

t u r v e a :.%id ~ n n i f o r r J y a o r c s e t h e f c r m a t i o n ,

and a

5''

c l a y ouahfon i a t i d t h e r e o n , The bs-kstomling and s u r r a c i n g a r e t h e n l a i d a a cr;, a n c r m a l f o u . n d a t i o n , Tws p o i n t s shou'rd be made c l e a r , f i r s t , t h e bottoming s h o u l d b e completed thr5aughout9

t h e n r e g u l a t e d bafopa t h e a p p l i c a t l . o n of t h e s u r f a c i n g , Any

s u r f a c e , If f u n d s F e r m i t a 2 1/218 c o a t of bftumfnous .nac adam s h o u l d be l a i d . Cn b s i n g l o a d e d , t h e p e a t i s compressed a c e r t a i n a7loun-L arid slnc-e, i n townshfp r o a d s t h e h e a v f e s t , l o a d i n g o c c u r s d u r i n g She p e ~ l o d of c o n s t r u c t i c n ( d u e -LC t h e w e i g h t of t h e constructional t r a f f i c f n a d d f t f o n t o t h a t of t h e r o a d s t r u c t u r e ) , nc s u b s e q u e n t f u r t h e y c o m p r e s s i c n of s h e p e a t f s t o be e x p e e ~ e d , A ~ o a d d e p t h of a t l e a s t 1

kt'

1s n e c e s s a r y o t h e r w i s e f a l l u r e .will G C C U P a t t h e edges. Before g i v i ~ g some c ~ s t s , i t 1 s n e c e s s a r y t c p o f n t c u t t h e n e c e s s i t y of making 5 0 f t , wid13 r e s e r v a t i o n S t r i p s t o s e c u r e t h e st a b i l i t y a t t a l n a d by cx3mfty o f d r a i n a g e w L d d e s i g n . Thfs 13 imperatfwe when t h e r o a d f s i n s i d e - l o n g g r o m d . Whem barikings a r e r e a u i r e d , t h e s e s h o u l d be of t u r f

s l o p e d a t 9 112 t o 1. Spof- dumps s h o u l d b e k e p t away f r o m

%he r ~ t i d ~ o f f l e t s and ? u l v u . ; r t s m u s t b e g i v e n s p e c i a l a t t e n t i o n arid a n a t t e m p t made t o d e c r e a s s che w a t e r c o n t e n t *under t h e of f l e t and c u l v e r t , E-.;en a t r e e drawlng water. f r o m t h e p e a t can produce s e t tl ernenl ,

S i n e s

194s9 28

m i l e s of new township r o a d s i n c o r p o r a - t i n g t h e abisve system havs b2en bu29': o v e r p e a t i n S h e t l a n d , The c o s t p e r m i l e f o r c o n s t ~ c l e t i o r ~ ( a l l c n o u t l y f n g s i t e s ) w i t h t a r g r o u t e d sulaf'ilcss h a s been w f t h l n t h e r a n g s &2,,800

-

f3,600.

Speed I n e o n s t ~ o c - c i c n was n o t e s s e n t i a h and r o a d s o v e r one m i l e i n l e n g t h wsre b u i l z s?l.;n" two summer p e r i o d s , Thf s a l l o w e d

volume ehangas i n lche p e a t f i e P d d o become complete b e f o r e %he f i n a l wopks were ur.dercak.°,n,

It

was an a d v a n t a g e a1 t h o u g h t n o t e s s e n t i a l .

Thus f n t h e on& woTd " u n l f c r m i ~ y " , l i e s t h e s o l u t i o n t o c o n s t r u c t i o n of l i g h t t a - a f f l c r o a d s a v e r p e a t , The one c o n d i t i o n n c t c ~ n t r a l l e d bsl.ng d ~ 0 u g h . i ; ~

It

1s v a s t l y d i f f e r e n * ~ w i t h .the problem of malntenumlcg of r o a d s o v e r peal; a s t h e r e a r e s o many unPcnowr1 f a c t o r s ,

l ? L g u ~ e 1 2 shews a t y p i c a l problem where e o n t f n u a i s e t t l e m e n t i s e x p e r i e n c e d ,

It.

happens where t h e r o a d h a s b e e n c o n s t r u c t e d i n cur-and -f ill. fashlcpn,

In

aPP e a s e s , t h e p e a t h a s been pmsumably f i l : s d o v e ~ , Some "draw" 1 s expex-f enced i n +,La p e a t f f e l d by t h e workings on t h e Pow side and a choked d f t e h is s u f f i c i e n t t o s e e t l e t h e r o a d , T h e r e a r e two a l t e r n a t f v e s , ons 1s t o l o a d t h e banking t o e n s u r e t h e compression of t h e p e n t t c

a p o i n t where no f d r t h e x - movemsn'c w i l l o c c u r , When m?,i3s of roadway ape f n v c l v e d , t h e c o s t of t h i s f s prcahfbf4;iv4 f o r s m a l l e r a u t h o p i t i e a . The o t h e r method i s n o t t c make up v.f: l-

g r a v e l b u t w i t h t u r f o r p e a t i n o r d s r t o avo1 d t h e f u r t h s n . l o a d i n g of che p e a t , There fs no g u a r a n t e e t h a t zhe unknown

f a c t o r w i l l n o t c a u s e f i l r c h e r d i f f i c u l t y a s much of t n e w e a k ~ e s s may be a t t r i b u t e d t e t h e paad m a t e r i a l s o r g f n a l l y used zhe r o a d ,

Nany s u b s i d e n c e s a r e e x p e r i e n c e d w h e r e a s h s l l o w p s a t s u b - b a s e o v e r l i e s c l a y on a s t e e p h i l l s i d e . Any e x c e s s i v e r a i n f a l l c a u s e s an i m m e d i a t e i n c r e a s e i n t h e w a t e r c o n t e n t of t h e p e n t a n d i n a r e c s n t c a s e , t h e p e a t became s u f f i c i e n t l y 11 cr~lid t o f l o w down t h e h i l l . I n t h e a r e a s w i t h s u c h f o r n a t f o n s , e x t e n s i o n o f t h e r o a d d r ~ c i n a g e sy s tern up t h e h f l l s i d e f s t h e o n l y remedy.

In

c o n c l u s i o n , I would c l a i m t h a t i f due c a r e i s t a k e n with t h e p o f n t s I h a v e m e n t i o n e d , g o o d r o e d s t o c a r r y l f g h t t r ~ f f is c a n be b u f l t o n p e a t a t low c o s t w i t h o u t r e c o u r s e t~a b c g - b l a s t i n g o r Icxrge s c a l e p r a - c o n s o l i d a t i o n ,

M r ,

E,R, McKfllop (D!-visional S u r v e y o r I n v e r n e s s

C o u n t y C o u n @ l l ) a a f d h e would make some o b s e r v a t i o n s on p r o b l e m s e n c o m t e r e d ' and e x p e r i e n c e o b t a i n e d i n c o n s t r u c t f o n and m a i n t e - n a n c e of r o a d s o n p e a t - l a n d i n I n v e r n e s s - s h i r e , P e a t i s d e f i n e d by t h e d i c t i o n a r y a s d e c a y e d v e g e t a b l e m a t t e r w h i c h , when c ~ t and d r i e d , i s u s e d f o r f u e l , I n f t s riat31;ral s f a t e p e a t h a s a h i g h w a t e r c o n t e n t and i s t h e r e f o r e a n u n d s s f r a b l e ~ e d f u m t o d e a l w i t h i n r o a d c o n s t r u c t i o n and a n u l : s a t i s f a c t o r y f o u n d a t i o n f o r a r o a d . T h e r e a r e , b r o ~ d l y s p e a k i n g ,

.;wo k i n d s o f p e a t - - , brcwn and S l a c k . The brown v a r i e t y h a s a

f 4 b r o ~ ~ s 5 e x t u r e and when d r y f s l i g h t a n d spongy. B l a c k p e a t i s h a r d and d e n s e w h e ~ l d r y w i t h a t e n d e n c y t o d i s i n t e g r a t e a n d c r u m b l e o n b e i n g h a n d l e d . F r o v t h e r o a d e n g i n e e r f s p o i n t o f vfew t h e two m a i a f e a t u r e s o f p e a t a r e i t s p o o r l o a d b e a r i n g c a p a c f t y and i t s p r o p e r t y o f s h r i n k i n g v 3 r y c o n s i d e r a b l y when i t i s a l l o w e d t o d r y , Ir, 1 n v e r n . e ~ ~ - > s h i r e t h e r e a r e c o n s i d e r a b l e d e p o s i t s o f p e a t and a l a r g e m i l e a g e o f roadway t r a v e r s i n g p e a t l a n d , T h i s i s p a r t i c u l a r l y s o f n t h e LYestern I s l e s and t h e f o l l o w i n g n o t e s a r e c u l l e d i a r g e l y f r o m e x p e r i e n c e i n t h a t D i s t r i c t . A d d i t i o n a l l y , i n p o s t - w a r y e a r s , a l m o s t 30 r n f l e s o f new s f n g l e w i d t h r o a d s h a v e been c o n s t r u c t e d , p r e d o m i n a n t 1 y on p e a t . N e w C o n s t r u z x B o n on P e a t

_-

A t y p e o f c ~ n s t r u c t f o n w h f c h g i v e s s a t i s f a c t o r y r e s u l t s o n p e a t i s t h e c o n c r e t e r a f t . It i s , of c o u r s e , e x p e n s i v e and d f s c u s s i o n of i t s m e r i t s f s o m i t t e d f r o m t h e s e n o t e s . Again a s c h o o l o f t h o u g h t a d v i s e s i n new c o n s t r u c t i o n t h a t p e a t s h o u l d be e x c a v a t e d c o a p l e t e l y and r e p 1 aced by h a r d m a t e r i a l s . Thf s i s a n e x t r e m e l y s l o w a n d c o s t l y p r o c e d u r e , The p r e s e n t o b s e r v a t i o n s d e a l w f t h more c o n v e n t i o n a l methods. On p e a t - l a n d , d e p o s i t s may v a r y commonly f r o m a f o o t o r s o t o a b c u t I 6 f e e t i n d e p t h . Deep d e p o s i t s a r e u s u a l l y f o u n d R d j ~ l z e n t t o roc^ o u t c r o p s and s u c h p o c k e t s a r e e x t r e m e l y d i f f i c u l t t o d e a l w i t h i n new c c n s t r u c t i o n and m a i n t e n a n c e .

!n _{~21e f i r s " , r e q u i r e m e c v . in c o n s t r u c t i o n i s t c d r a i n a s}

a 2 e i q u ~ t e l . y a s p o s ~ i b ' , - e a h e a d o f for ma tier^ work, Serle:: o f w e l l lo:.ated o p e n d r a i n s w i l l r e d u c e t h e w a t e r c o n t e n t , o.f t h e p e a t , and w i l l , I n . a c o m p a r a t i v e l y s h o ~ t time, m a - t e r i a l l y i n c r e a s e i t s l c a d - b s a r i n g c a p a c i t . y . It should, b e r e m a r k e d t h a t e x c ~ . v s t i on i i i p e a t b e l i ) , ~ ::h.: zar l-iagaway f s b e t t e r av'cidod and formation in

., ...

emb s.nl;.nar,. t.. P ~ # Y ' % ~ ' ~ I " ~ C J L. J:. B 3 t reg a r d i q ; d r a i n a g e of t h e f c u n d a t Ton,

c a r e s h o ~ l d k.2 s x e - c i s e d t h a t . t h l s f s n o t c a r r f e d t o t h e e x t e n t c f f c r m i ~ g w f d e ~ i i d v e r y d s e p d i t c h e s c l o s e l y a d j a c e n t t o , t h e

. ; a r : r l a g s h a a 9 f ' ~ r s;e;;hc;pz rno13e i m p o p t a n t 1s ample l a t e r a l s u p p o r t

1 - i : ~ f3.e p c a d ,

Ir:

i - , ~ , ~ i t ; q i s u c h as t h e W e s t e r n I s l e s w h e r e avaii.%:~i?le

n a S e r b l a 1 a a r s c c n f b e d t o p e n t and r o c k , embanlrments a r e f r e qi.le11t;:i.y c o n s t r u ~ t e d i n p e n t u r p e a t turf'. T h f s c o n s t r u c t i o n c a n b e fa:'!.r;ly

5 --, , ~ n g

-

b u t .:hr.inknge and c c n s e q u e n t s u b s i d e n c e o f s u c h embankments

c;ar, t a k e p i a c e s l c d l y ;rTT3r a p e ~ i c d o f y e a r s a n d c a u s e t h e ; z ~ " _ r t a g e ~ a y L C . l c 3s :?hape. The l n s s of s h a p e c a n be s e r t o u s a n d r v . i l l b e r e f l e c t e d 9. h e a v y m a i n t e n a n c e , 1% f s recozimended t h a t embankments b e c o n s t r u c t e d o n l y p a ~ - t ; l . y fn pe3.t. A t r e n c h o a t l e a s $ t h e w i d t h o f t h e v e r g e , should. h e e x c a v a t e d i n t h e p e a ? on e a c h side a n d t h f s s t o n e f i l l e d a s

h i g h a s n.:afer;fal ~9111 a l l o w . The t o p and o u t s i d e of tohe bank c a n

b e f f n i s h s d c f f 4n p e a t , Th:' ,s w i l l z o n t d n and l o c a t e t h e L'cundtiti en wb.ich. c a r r f e s t h e r o a d , I n c r e a s e t h e a l l i m p o r t a n t L a k a r a l s : ~ p p o r t , b e s r c l s s p r o v i d f n g u s e f u l s u b - s o i l d r a i n a g e .

V e l a g e ~ cr1i p e a t r o a d s s h c u l d b e 17ade a s wfde a s p o s s f b l e , and, i n

any c a s s , a m a not; i n ~ o n s i d 3 r a b i e f 4 c t 0 r 5n r o a d s a f e t y ,

En f o r v f n g t h e c a r r f a g e w a y i t i s i n a d v i s a b l e t o b r e a k t h e tmrf whi2.h. ::c.nsry t h e p e a ? . If a m a t o f s a n d , g r s v e l o r a s h e s

can b e l a i d t h i s i s v e r y w e l l w a ~ t h w h i l e . I n m y e a s e l a r g e s i z e d

~1Y.t.chlng eho!lld n c 5 b e l a E d o n p e a t . Euch b e t t e r r e s u l t s , w f l l be

c?,t,alzed w f t h a l a y e r c f h a r d c c ; r e n o t e x c e e d i n g

4'?

t o

6"

in s i z e

:~;llr 5.tc.ns. T h 3 1d.e;3 i s t , ~ l a v a mat o r r o a d c r u s t o n t h e p e a t

as?

n ~ 3 t . 9 t c ~ c . a r r y t,hs t r a f f f o env4.saged r a t h e r t h a n o v e r l o a d the

1:6aS) d i t h h e a v y bot.tcmfl?g which w i l i p r o b a b l y p e n e t r a t e t h e p e ~ t w i t h unfcr)tclr.ate r e s u l t s . W h e ~ e e x c a v a t i o n I n p e a t i s n e c e s s a r y ~ t ; L s b e t t e r t o l a y dcwn s t r c n g trrrr o n t o p f f n c t h i n g e l s e f s a v a i l a b l e ' ~ 3 f o r ~ : - 3toi-1e f f l l f n g , The m c s t f c u n d e ~ o u s s e c t i o n s of p e a t a r e f r e c j a e n t l y f o u n d a d j a c a n t , t o r o c k o u t c r o p s , The t e n d e n c y t o g r a d e o v e r r o c k o u t z r o p s s h o u l d b e avo1 dttd, The o u t u r o p , w h f c h m i g h t j u s t be c c ; - ~ e r e d , s h o u l d b e ~ e r r l o ~ r a d t.s below f c r m a t i o n l e v e l , otherkrl.se t o o h e a ~ y l c a d f r l g of t h e p e a t c,n e i t h e r s f d e of t h e o u t c r o p i n g r a d i n g c v e r i t , t ; i l P c a u s e a bump e v e n t u a l l y d e s p f t e a p p a r e n t l y good g ~ a d f j z g a t t i m s : ~ f c o n s t r u c t i o n , S5st'lemen", fs bound t c o c c u r on a r o a d c o r i s t r u c t e d i x

p.=a.t and t i m e s k o u l d b e a l i c w e d b e f o r e t h e f i n a l surfacing i s a.;tarrrptftd, C i p c u m s t a n c e s may v a r y b u t a y e a r i s n o t tea l o n g f o r s e t t l e m e n t . When s u r f a c f n g i s u n d e r t a k e n i t i s f e l t t h a t a . ~ i l ~ . ? o o a t o f pr.e@c.ated s t o ~ e , f o l l o w e d b y a d a r p e t c o a t , all a p p l f e d f z h o t s t a t e , p r o v i d e s t h e h e s t r e s u l t s . The a ~ ~ r f ' a c e

h a s t o p o s s e s s t h e a b i l i t y t o b e n d 02 f l e x w i t h o u t b r e e k i x l g ar!d

a s t o n e c o m p l e t e l y p r e c o a t e d and, t o some extent;, l u 5 r . l c a t e d -by

t h e b i n r ? e r sppe9r.s t o p o s s e s s t h i s q u a l i t y t o u t;rez.i;sr* exte:?i!;

t h a n P g r o u t e d c o a t . The s u r f a c e should., o-f" c o : i r s e , b e w : : t ; a ~ p r : ~ , ~ f ,

The c o ~ l s t r u c t i o n o f c u l v e r w t s i n p e a t p F e s e n t s nxny p r o b l e m s . If t h e p e a t i s n o t u n d u l y deep t h e r e i s good. r e a s m f o r e x c a v a t i n g t o t h e h a r d , b u t a g a i n t h e buvp o n t h e c a r r i a g e w n ; ( , w h i c h w i l l mark t h e : p o s i t i o n o f t h e c u l v e r t , w i l l become 5nc;:;raessinglg e v i d e n t a s t i n 2 g e e s o n . F o r c u l - v e r t s up t o 2 f e e t +ride ?!ias3nrb;y

o r good d r y s t o n e w ~ l l s c a r r y i n g p x 2 e - c a s t s l aba Rre s ~ . t ; i s r a ~ i ; 3 r y ~ P f p e c u l v e r t s h a v e t i ~ e l r u s o s , b u t i t 'has t o b e r e m e m b e r ~ ~ d t h a t suSsid.ence, d u e t o u r , e r ~ u n l l o s d i n g o n c a r r f a ~ e w a y 2nd v e r g e s , c a : ~ c a u s e s u c h d i s t o r t i c n a s t o r b e n d e r t h e c u l v e r t u s e l e s s . Wherbe e x c a v a t i o n t o t h e h a r d 1 s i ~ r a c t l c a b i e c u l v e r t s c a n be suz!Pessl"ul:!.y c o r l s t r u c t e d 03 s l a b s o r ' b ~ t t e n s w h i c h s p r e a d t h e l o e d or_ the f o u n d a t i o n . C a r e h a s t o be e x e r c i s e d i n s i t i n g c u l . v e r t s and 2.0 more t h a n a r e a b s o l u t e l y n e c e s s a r - y s h o l l l d b e c o n s t r u c t e d ,

I n new c o n s t r u c t i o n t h e aim s h o u l d be t h e Formfng of a r o a d t o f u l f i l t h e f o l l o w i n g r e q u i r e m e n t s : - ( R ) A b f l i t y t o c a r r y all r e a s o n a b l y a r i t i c l p a t e d t r , a f ' f i c , ( b ) A b i l ~ t y t o r e t a i n s h a p e and p r o v i d e a i;ocd r b u m f n g surf a c e . T h i s c a n b e a c h i e v e d b y c o n s t r i r c t f o n i n embanlcment. If m o r a i n i c m a t e r i a l i s a v a i l a b l e and a c c e s s i b l e , a11 t h e b e t t e r ,

I would l l k e t o r e - - e m p h a s i s e and summarise t h z rna't;tors r e f e r r e d t o : - 1, Adequate s u b - s o i l d r a f n ~ g e ahead o f c o n s t r u c t i o n , 2. Af'fopding t h e maxinun l a t e r a l s n p p o r * t . T h i s i s V S P - ; ~ i m p o r t a n t .

3 .

C o n s t r u c t i n g embankments on a s t a b l e f o o t i n g :xrn.. ,-ly~vidPlj.,: . - a d e q u a t e v e r g e s , w h i c h on a s i n g l e w i d t h r o a d sh.od,.ia be

3

f e e t wide a t any r n t e ,

4.

A v o i d i n g d e s p d i t c h e s whf c h j e o p ~ r d f s e l a t e r a l s u p p o r t ,

5 .

Constructing mfnfmum of" c u l v e r t s ,

6 , P r o v i s f o n of a m e t , evrtn of' t u r f , on p e e t .

7.

U s e o f s m a l l h a r d c o r e c a t h e r t h a n h e a v y p i t ~ h i n ; ; ~

8

Removal of r c c k o u t c r o p s w e l l b e l o w f o . t 3 m a t i o n ,

M a i n t e n a n c e o f Roads o n P e a t

a p p l i e s a 1 s o t o v n i n t e n e n c e

.

Much o f t h e f o r e g 0 1 n ~ ~

i i o a d s o n p e a t s h o u l d b e s u r f a c e s e a l e d w h e r e v e r r e s o u - r c e s a l l o w . The r e t e n t i o n of t h a t waterhprooi' s u r f a c e i s asser;tis!-. The p e r c o l a t i o n o f water t h r o u g h t h e r o a d c r u s t d o e s r:.ot.ki:ag t o i n c r e a s e t h e s t r e n g t h o f t h e f o u n i i ~ l ; i o n . When t h e c e r r l n g e w a y l o s e s s h a p e A c r o s s a t r a n s . r e r s s s e c t i o n , t h e c a u s e s h o u l d b e i n v e s t i g a t e d . If an enbankmsnt 1 1 ~ s s u b s f d e d t h i s s h o u l d S e r e c t i f i e d when r e s h a p i n g i s d o n e . Uneven s u 1 , s i d e n c e or1 an

o t h e r w i s e w e l l s u r f a c e d r o a d . n d bumps d u e t o c u l v e r t s e n d r o c k

o u t c r o p s d e v e l o p i n t f m a a n d c a l l r e n d e r t r a v e l s l o w a n d ~ i q ~ ~ i ~ ~ f o r - t a b l e . ( s e e F i g . 6 ) . The expense o f c o n s i d e r a b l e r e g u l e t i n g and

r e s u r f a c i n g may b e u n d e r t a k e n alrd i n d.ue c o u r s e i t i s f ourid t h a t s u b s i d e n c e h a s a g a i n o c c u r l ~ e d and t h s u n d i l l a t i o n s r e a p p e a r . The c a u s e may b e o v e r l o a d f n g o f weak s e c t i o n s of p e a t , It m i g h t t h e r e f o r e b e b e t t e r .to s w e e t e n n u a h undu1e:tfons b y l i g h t r e g u l a - t i n g r n t k e r th,m t o atl;e?rpt, t o e r a s e them e n t i r e l y . E v e n spreadi:13 o f t h e s u r f a c i n g ater rial 1 s v e r y i m p o r t a n t . H o l e s c a n o c c a s l o n e l l y a n d s u d d e n l y a p p e a r i n a c a r r i a g e w s y w h i c h i s c a r r i e d o n p e a t , ,

Z x p e r i e n c e s u g g e s t s t h ~ t i t f s b a t t e r t o f i l l t h e s e with sand r a t h e r t h a n s t o n e , a p p l y a l i g h t h a r d c o r e c r u s t ; and r e - s u r f a c e .

A g a i n t h e s u r f a c e of' t h e r o a d may b r e a k b a d l y arid p e i i t ccme r i g h t u? tc +;he s u r . f a c e . S11.ch n a t ; c h e s h a v e , n f r n i j r d e r t o b e c u t o u t a n d i t w i l l be n e c e s s a r y t o e x c a v a t e t h e p e a t b u t n o t d e e p l y . It i s s u g g e s t e d t h a t on a d e e p d e p o s l t n o t more t h a n a f o o t of p e a t b e removed. Two o r t h r e e l ~ y e r s of 4icssian c l o t h

w i l l p r e v e n t t h e p e a t a g a i n w o r k i n g up t h r o u g h t h e r o a d ~ ~ ~ 1 s t .

A l i g h t i n f i l l i n g I s u s e d o n t o p of t h e h e s u i a n .

D r a i n a g e i s of c o u r s e e s s e n t i a l b u t i t w e r e b e t t e r t o

a v o i d m & i n g e f e t i s h o f d e e p l y dug r o a d s i d e d i t c h e s , C u 1 v e r . t ; ~ and embankments s h o 0 l d r e c e i v e r e g u l a r i n s p e z t i o n and any e ~ i r i e r i c t ; o f movament i r l v e s t f g a t e d and r e c t ' l f l . e d .

One f e a t u r e o r d l . s a d v a n t a , g e o f r o a d s c n p e a t v~hick- is n o t commonly r e a l i a e d f s t h e s l u g g i s h n e s s and heavy f u e l . consuq:tic;ri

of ccmp e r a t l v e l y s l o w l y rnc vfrlg 1 nderl v e h i c l e u . The t e ~ m ~ e k i C i l a d r a ~ ' h ~ 3 b e e n q p l i e d t o t h i s f e a t u r e o f t r a v e l l f n g on. p e a t r-oed;;, s n d , i n c e r t a f n c f r c u m u t a n c e s , c a n b e v e r y n o t i c e a b l e , a n d i n d e e d t h e s u b j e c t of much complairit. It may be t h a t i n v e s t f g a t f o n c o u l d b e c a r r f e d o u t I n t o v a r i o u s t y p e s o f s u r f a c f n g b y sorrleone w i t h a l i t t l e T o r e t twe t o s p a r e t h a n t h e averRge s u r v e y o r ,

DISCUSSIOILI OI\i I)~?'LTTI!~.GII~ S 'liD ZCIIILLGP

-

IS PAPERS 013 PZ:IT

-

r7 ~ 1 - l e Chtif~nian o y e ~ i j d -the d l s c u s s - f o n by- sa::?.a~; i,k;::tt.

T -

i,ii ..., , D r y b u ~ + : - . ; h i 3 ::rid. I{cKl].,lcpl s p a p e r s were t;l;~~ll:;e~~.r+:s

a , i r n i , g t &:i ~ 3 d ~ : :;lya~:.Y,:~ f o p i : ~ l ~ l s t r . ~ ~ t i ~ ; ~ of ~ i ? : ? ( j . s C Y T J ~ T . ~- k)e c ! . ~ ~

mlfi w l . ~ . I . ~ , ~ k . z 9 l ~ i . r r ~ ~ - e l f ~ h a d p r . e v 4 r ; u a l y f e l t the 11;1;2blei-? :,c ';;e

e i r , ~ c s t n !1:,153::3,?2i~ ~ 1 1 3 ~ it, nuii s p p e n r e d that f - t L J H ~ by i1cj rre:;rr:3

11nac;lyable. 1:. ;-.t.;.~.m>. L h J ; . ~ h : ' ~ _.,? C O ~ ~ S ~ ~ ' L ~ C % I O ~ o v e r 1,9r?!; ~ F S

o b ~ , ~ i ; ; ; : s ; . y .t;,. 13.3 :''le,~ii.)i.e, I t is s u r p r . f s T n g .tkai co:lcr-et;e ,;~1.;4cll

i s n o r r r ! a l l y ragaxdsci a s a rigiix pavement; sllotild h x v e been s o

c f l . C o u l d

Kr.,

i . l c K L ' i l o ~ s a y hob7 t h e s u d d e n f t i i ' l u r ~ s he

rnen.;fo-.ls ~ 2 ~ 2Di> ~they 7 a ~ i . ; e f r o m th:: ps.ss:ige of sorne ?isa.vy

v e h l c l e ? Wh8.t: I.~OLI; d b e the Ifrfiii t,

I:!

t h e t y r l f f i c loading '!;ha+. h2,e r ~ a d : ; c.ar! carry.?

PIP, I"lcBL13.?p r ~ e p l Ced Zh3-C; w h i l e f a f l u r e s w e r e of belr

dile t o +;he c o n s t ~ u c + : . i c . n b a i n g iilsnfffc',cnt:y irnpe:rvfous t o p r e ~ e n t t h e p e n t uorlc5.ng throug'rr .it., p a r , t l . c u l a ~ l y kiesvy l o n d a

woxld, c f c c u - r s e , h a v s ar. ef'r"ac.5, Failures seem o f t e n t(; $aa!ie

t h e 7 s r . m o f a &r,-tall :zl~Sz;idense i;z Ens w l i 2 e l - t r a c k which t h e r e a f t e r

t,akes more tha.1-1 i t s P a l p s h a r e of l o a d a n d t h e f a f : ! ~ ; ? e i s r s p i d l y

rr1ed5 wo:-ssb T J r i f c r t m a t e l l ~ I , J ~ W G T ~ by : T ~ ' f a l a n d e r r c r and h a v e

n c t h e c r y ~J;I wilf.;h +;a 1 : ) ~ s ~ a u r ac t;fcrls3 & h e r s f c : r e f t ; f 3 ??spy

d i f f ' i c a l t , t:, e;;llairi. e l l t h e d e f o p ~ ; . , a . t i ; r l s which cceur, We dc, n o t

kncw what hhppens t,c; t h e peat .2~2I-7:s~ .:.he r o a d a , t the 2iff'eren"r

~ e ~ ~ ~ j r ; l ; , , 1.i:; . ~ G uld b e most ~ . s e l l : ~ ' i '1.5 a t ; f n v e s . t ~ g a t i . c n co2i.d t;e

mads t c :give u s m s F n ' . i ~ s f c knosni:lsagf! oii t h e h e h s v i c ; i ; ~ cf t;!r..ie ps:,t. Ons sl;i:~;~.irr: ' t ~ ; ~ e sf inv.estigat.Ton .wh:ich might be c a r r a i e d

c9.t 1 5 t.6 make a c ~ r e f u l p;?~.?iYlz c11? t h ~ peat under ;! m a d whlch

taks,: L'aZp'ly h e a v y i ; r n f l " f c arzt3 t h e n r e l a t e i t .tci s u b s i d e n c e s t h a t Occ:iF a t d L f f ' e r s n f , 59.ves.

Ccl. P a c k - w o ~ d

-

( F c r e s t r y C c m r ~ i s s ~ s n ) congratu1::tect 'the s p e ~ k e r s c j n t h e i r . v a l u a b l e F a p e r s a ~ d . t h o u g h t t h s i ; ,the v i e w s t h e y expresse3. bepa diarne t-r.1 filly cpposf t o t o i>ne e r i o t i - I ~ F , Irj.

g e n e r a l , t h e 70restr.j C o 7 ! n i l ~ ~ l o ; l ?i;:ro~;~r

KT.

J~lcICi:l.lop's r n s t t ~ o . i s .

T h ~ g c o f i s i d ~ r e a r l y d r e i n a g e o r the p e a t ; t o be n e c e s s a r y :ifid.

i r s a a l l y c a r r y o l l t such d r ~ i n s g e a t l e a s t a y e a r befcrcl P h s 1'0ad

i ~ : o n s t r u c t e d . D ~ a f n s a r e c u t w:.th B h e a v y d r a f n a g e ~ l o u z h

2 f e e t 6 f n c h s s d e s p and .they must be sl.t,el! so t h a t t h e y rlc n o t

r e d u c e t h e l a t e r a l s u p p o r t g i v e n by Lhe s u r r o u n d i n g peat, t o the, r o a d - b e d . He a g r e e d with t h e speakeras on t h e n e e d f o ~ t h e r o a d s u r f a c e t o b e P r q e r v i . s u s , S u s h su.r;.f a c i r ~ g s a r e u a u a i l y m d e of s ~ r s d y c r s l . l t , y r i v e r g l a a v s l f m r o zom.3 n e a r b y s t r e a m ;?n.il . t h e c o n d f t i c n cf t h e r c a d f s s o ? ? t i r , u o c ; s l y m a i n t a i n e d by g r n d f n g the g r a v e l b a c k f n t . c t,hs w h e e l t r a c k s . R a l s e d r o a d s ~ h c ~ h i s e v e r a l a d v h n t e g e s , one ~f w h i c h is . t h a t t h e y shed w a t e r ~ ; a . i c l r l y bnd t l z e g do not n e e d t o b e p r o v i d e d w i t h s i d e d r a i n s , A ~ c s I l e , . i ~ i ~ s fa. t . h e Contmission h a d h a d c o n s i d e r a b l e s o c e e s s b y using a w o b b l e - w h e e l e d r o l l e r t o r o l l t h e r-oad-bed b e f o r s c o n s t r " u c ~ t ' i o n was s ' i e . r t a d .

S u c h a roller- >ill1 a l s c flatten the v a g e t ~ t i o n a n d s o proT:icie a

-I ar..33

Ccl. Packwood tjen-t o n t o say that. many d e l - t ;

;.-r.:r' ,lL. i l ii 'r-lau-e iead a k s u i ; t h e use o f ~ ; e r t , f c a l sa n d d r a i i i s abroad,

a r i d h c L r ~ t e n d e d a+, the f : . r . ~ t : o p ~ c r % u n i t y . t o m e k e some :.est w l t l i

tilz-1 .:.;- f c.';*f~ '; I - O ~ ~ S

i a s t ' l y , he . Y J O I I ~ ~ l f k e t;o ~ r , s n t i c n c u l v e r t s . The

C o ~ m - r . P ~ s i c . i ! . h a - 4 ~ f o : ~ n d s h a t b e z a u u a oT -1.lie l a r g e s e . t t , l e r r i e n t s ,

; j t , 3 ~ : ' ~ . t ~ a l ve;-ts a r z t h e rnos!, su9::e'r:ia ~ C P * u s e C R r o a d s o v s ~ p e a t ,

I ,sci-c,-:. of .;ha well:-kn~w;- t y p e s a r e very experisfve and

t;h.<; \, ila u s e d

-

~ . l , , ~ . , t . r . , " ,r :.-i

.

~ n d ; h e % p o r ~rres ~ i . r i h S U . G ~ ; ; ~ ~ S S . i.jhen al.1

r _{2 ,.2} .. 7 :- + L,eriieri5z _-' had t a k s t l z;i aca, 1,: s h o u l r i b e p o s s i b l z t o e n c e s e t h e

-

. <..,* 2' P ~ I ' L S In ;: 3 n i : r e t e t r3 m a k 3 them perma.n8,n..t.

iViro D a k e r s ( f i n i s t r y o f T r a n s p o r t ) r e f e r ~ r a d t o a mile

---

I L J ~ ~ " c A ( ? .::n A , ? b ~ t w e e n BlaSr Ar;iiu':l end I n v e r n e s s whi.ch vjas

f c ~ m e d of c o n c r e 5 . j s l & a and. wh3.c8h r a n o v e r p e a t

1.5

f e e t d e e p

a122 ~ ~ 2 . 3 . ? . a i d I.n 1927 arid i s si,411 I.;:;. good condf t 9 . m ( s e e Fig, 1).

Ir;

?:?-IS r c a d , the s l a b s he-vs e f d e - b e a m s t c r e t a i n t h e subsofl.

a::d .;'veriapp%ng beams a t 5he c a n t r e and t ~ a n s v e r s e jo i n t s t o

p r e v e n t r e l a t f w e rnov.xi!ent b e t w e e n s l a b s , The r a f t is 21 f - 5 , wide :..r~pptsrting

1 0

f""., cerrfa~p,ew~y, tht? c n c b s r t s 1 f n

59

ar,d t h e

s l a b 7 - r . . _{*va;lij Z ~ i i i r r ~ . .} \ , -.. _G.:.iCi 66 ., _i i t , _{i i t i i 1 ; . l ' i j - ~ ~ ~ ~ ' ~ e 1 1 i , L - O I ~ S ~ S ~ S}

i;f' t w i s s e d bar: fsrml.ng a mssh at. t c ' p and b o t t c m sf t h e slab, each

rn-

layer; -L<.7ighir_G

7

1.,'2 l.'r.la, ;;,+: .-(lo y d . I n e r e is i n e d d f . t f t 7 n d i s ~ o n a . " : rr-;l~i,"crcerneni:; u:aighir,g a f;;r't;kor.

3

:;be p e r sq, y d . m d f ;!r

3

f t ,

cn each s f d a ..f the 51 n n a v s , r s a QdSnt:3 *:here i s mesh reinfclreernlsrit .wslghfrag

5

i i r . 1 , p a r sq. y d , Thz 5 I c b is 8 Pn. t h i c k , t h e b o t t o m

6

5, I;? 1.; 2.4 c o n ~ . ; e t 3 ar;d ckia ?;cp 2 i n , c c n s l st:; o f 1:1 1 / 2 :

3

c ; c . ~ ~ : , : . r e t a using t j ; ~ a r l l + ; e c h i p p i n g & ,

A less e l a b ~ ~ r a t e t y p e of s l a b .was laid b e t w e e n Speali

.r, 0

~ j p ~ d ~ . : ~ _5' mid 7'1~)z-k k J i j ? i a m b e f c , r e ?he s e c c r i d w a r . The s l a b s a r e

40

arid t.3 ft.- longp

6

i n . %hick. and t h e o i i t s f d e e d g e s were a g a f n

t h i . c k a n s d t o

15

id'2 .f.n, The kh-izk e d g e s a r e r e f r f l o r c e d w i t h

3 / 3

.in. bar? ur,d he ::..8nt~.& jcini; had a I c a l g i t a d f n a l

V

and t h e s l a b s ax35 .LCI'~T!.-~C';.~~ b y

3,/4

IIY. d t s ~ 5 i haps a t . 30 in. c e n t ~ e s , The t o p

w e < , ,,nfi.r~:arnar!.~. k.cr:;;ha

7

1./2

:Lo

p e r sq. yd. a n d a d d 5 t f o n a l ;%a51

at;

5

Its, p e r so. g d , i . 5 p r o v i d e d o v e r a l e n g t h e f

5

f t . a5 t h e

snd3 cf s a l h : > l a b , Bct,t.crn relnfc.rcernar,t a t

7

1 1 2 p e r sq. y d , and s h e a r ? ~ , ~ . r ? f c r c e . r l s n t a t

3

I b , p e r sq. y h . is a l s o p r o v i d e d , Again

i.:nls .c,r;dpse c 9 n ; c r e t e w a s .J-:&,

I

+ e consf d e r a b l e s e t t l e m e n t

h a s c c z i r r ~ e d b u t t h e r e h a a t e e n i 3 ~ s l a b failares ( s e e F i g , 10)- J t i ~ t . k s f ~ . r . s t h e w a r o t.r..d s p a c l . f f c a t i c n wac.g sTmpl8f f e d a g s f n and cr, .!;he Cra:after C o ~ n t f a s S:hsme, 5he s l a b s still 40 2nd

50 ft. Lofig a c d

8

in. c h i c k h a d nci t h f c k 9 n . e d e d g e s and t h e j o i n t s

-+,,ere o f t h e p l a i n b u t t typt? with 3{'li. 3 3 . 3cweP b s r s , The wiLn

r e i . n f o r c a ~ e r , f 1/1: Ln, r,wiur?ed bars a t 6 I.n. c e n t r e s L a b o t h m

d l ' ~ r ~ ~ . r t . T ( ; l - i s ic tho P a y e r s w f t h e x t r a b a r s t a t t h e c o r n e r s , 11:s

2i;fisret.e Inj.as : 2 th;-c.*hcu.t. T h i s s p e c i r i e a t i o r i was u s e &

'be t.b;.?er, l J e i ~ t ~ ~ m i . : ~ e ar,d Laggafi F 3 ~ f dge , The slabs s e t t l e d c o n s i d e r a b l y al;d .,et~qe s l a b s b r v k s ar13 .;he r o a d had t o be c o v e r e d with l ) . l % ~ r i l . -

i r ~ s l a b de,sign k:.ad any s i g n f f i c a t l t . c f f " e s t o n Lhe S,eh:~vfosr n,'

t h e r o a d bu:t ft: saems t h a t t h e ~ S ! . L H V ? - O ~ X P of c o n c r e t e r o a b s c o i l s t r u c t e d o v e r p e a t f s f ~ i s v i t f f ~ i e r : k l y c n d . e r ~ t o o d . 5.nc;thzr.

m a t h o d of c o n s t r u c t i o n used i n t h e C r o f t e r C o u n t i e s S c l i e ~ e ? ~ s , -

t h a t of complete rel~ov:!l o f t h e pe:qt;, I n one scheme carmaied uc;.;:

slnn=e t h e w e r where t,he p e a t d e p t h w ~ s 1 0 f t . , f t I ~ ) . : > s t o u n d ? ; h t a l m o s t t w i c e t h s t h e o r e t f c a l arrctunt o f p e a t h a d t o b e remove(3

See,a:ase of' f l o r ~ .which took p l a c e 4.ntc t h e e x c a v a t f o n ,

P a r t i . o l e x z a v a t i o n t o H~CIUT.

3

f t e w f t h b a c k f i l l l . n ; - ; o f ~ I R ~ ~ Z O P B h a s s o r n e t l n e ; ~ b e e n adopted b u t f t would seem t o 'oe n

m~:~;ls", a n s u i t a b i e methx?d a s I t rernovea t h e f f b ~ o u s t o p l a y e r ar,d o v e r l o s d s tihe p e ~ t . T h i s method was used i n p a r t on t h e Glerlcoe m a d and It; is s t i l i s i t b s i d f n g a f t e ~ a b o u t 20 y e a r s .

Tkis nle t h d of e s c s t r u c Ling ;?odds Ijn s h a l l o w emb ur,lr:r,ent. which l e n v e s in p l a c s t h e f 9 b r o u s @r*i;s.t, cf" t h e p e a t a p p e a r s t o be ~ u i t s ~ u . ~ t e s u f u l anC h a s been used on r e c e n t C r c f t e ~ Courities Schenes. 1.5 r e V a l i n s t c te s e e n , l i a w e ; ~ s r , whether t h e r e will be v e r y much. settiemeri-L, P o s j f b l y t h e ernbmkrnent s h o u l d b e sxte:idetl

at; a s h a l l c w e r d e p t h , on e i t h e r s f d e of t h e r o a d , t o p r e v e n t the p e a t . t h s r e Eje1;lg 2 q u e e ~ s d up, A rne~,hnd of d e s i g n i n s such rzrl

rmtiacicrnent, ei;d sl.26 k $ ~ r n . _ : , b a ~ e d , I %;el f e v e , on a t h e o r y p ~ o d u c e d by T e r z a g h l d-css s x f ; z t ,

I p e ~ s c r l a l l y s h c u l d iike t o s'-se bog S l a s t f n g u s e 6 i n t h e B l g h l m d s a n d r?rhaj._ ne.w ma j c r w i ? ~ k s d o s t a r t up a g ~ f n ~ i t

<nay b e p ~ s s i b l e t o t r y i t e x p r ? ~ l . m e n t a X l j . I b e l i e v e t h e methad was gssd i n Germany b s f o r e t h e war,, d r z p s t o t a l l i n g 7 0 ft. t2hroug;i

d,eep p e a t 3 o g z b e i n g achf eved. The German a u t h c r f _ t i e s , I u . n 6 e r ~ t a n d ,

= c # r ? r i d e r e d t h a t f ' c ~ d e p t h s o v e r 15 f t . o r d f n a r g exceva.tior, i n p e s t

as unsconerxlc.

l";i;:,, R c : ? ~ (F~::~wsf:lay C ~ ~ ~ m i i s ~ : c . ! ? o s a f d t h a t he r.~ould P i k e

f i ~ s t t o si.at.6 two f a c t s , One i s ' ~ l i a t the Ccm~Xssl.on used t ~ a c t c r s o v e r sof rL pest and 'ihesa c a n r u n s;-ltisf u c t c r i l y when t h e p r a e s s a r e

cn t.he p e & % is 2 112 l b s . p e r s o , i r i , 'uv'e a l s o know t h a t t h e rnaxirnum p r e s s u r e we g e t on a r o a d s u ~ f ace f s t h e t y p e pressur:e cj.f

t Y + s ' l o r r y , Can the R ~ a d F i e s e ~ r c h L a b o r z t o r y t e l l m e f f s o i . 1 rnecilanic,a moasu1ae~erit.3 show w h ~ f l ; d e p t h of c o x i ~ t r b u c ~ i o n w S i P b.2

n e e d e d t o spread o u t & p r e s s u r e o f 1 0 0 lt=./sq, in, o n tke L c : , ~

stlr.!face f o g i v e a p r e s s u r e cf 2 l j 2 l b , / s c , i n , CI: t h e p 5 s t ?

Pir. T ~ e s i d d e r b ( R c a d R e j e c r c h L a b o r a t o r y ) re-,] ..Ted tl-lat

t h e r e a r a t w o thing;; scz know abcut p e a t : cne f s I t s v e F g l o w

s . t r e n g t h and t h e o t h e r one i s t h e s e t t l e n e x t which t & e s p l a c e

l11 s e a t when it f l o ~ ~ d s j d . T h e r s i s l f c t l e doubt t h a t ~ : , s l c a l q t i o n s c o u l d r e a d i l y be ~ a d e TO show wliat t h i c k n e s s of c o n s t n l c t 5 . o n 1s r e r ! u i r e d t o rad1.1ce t , o 2 1 4 2 1 b , / s q , 4.n. +,he p r e s v u p e cr! !:.kt2 pe;e:t. clue +,o t r s f i ' f e., T h i f ~ r t u n a t a l y .the wel"ilt. o f t h f s ?hiclir1ess o f c o n s t r u c t i c n hiou'id be so g r e a t t h a t f t would c a a s e colisoiidz.i;for:

G?' t h e p e s t , t h a t i s t h e x a t e r i1el.d f n t h e p e s t f i l m s \~\l~i:!l.d be

s l a b i l y squeezed o u t and s e + l , l e n n t - ~ o ~ z P d ccc;ur. S u s h s e t t ; l e ~ l a n - t .flight go 0r.1 f o r a ~ ~ u r r ~ b e ~ 07: y g a r s tln3 s i n c e p e ~ t i s n o t 8 :~.n:fom

rnaterLe.1, t h e s e t t l e m e n t w i l l b e u n e v e n :ad t h e r o a d w c ~ 1 . d t h e r e f o r e become bumpy and i m s a t i s f a c t o r y , The t ~ c u b l e i s not; o n l y t h e L s s r l n g c a p a c i t : ~ of t h e p e a t b u t a l s o t h e arcaunt of s e t t l e m e n t w h f c h i s l i k e l y t o o o c k r .

X r . D r y b u r g h i n r e p l y s a i d t h a t he a g r e e d w i t 2 1

Xr. X c K i l l o p s n d t h o u g h t n5.s r e m a r k s on m s i n t e n a ~ c s were v e r y

r e a l i s t i c and t h e y d i d r e p r e s e n t t h e p r o b l e ~ a s w s knew it. The f i r s t t h . i n g ts d e s f d e when 3 t ; a r t i n g t o b i l f l d a p e a t r o a d i s w h e t h e r y o u v ~ i l l b ~ i l d n 1 f g h . t r o a d w h i c h w i l l f l c a t on t h e p e a t as it e x f s t s c r w h e t h e r y o u a r e g o i n g t o a t t e w t t o c o n s a l i - d a t e i t a n d b u i l d a more c n n v s n t f o n a l r o a d on the t ~ g . C o l .

Packwood by i n t r o d u c i n g v e r t f o a l s a n d drpains i s l i k e l y t o f a l l bebween t h a two i d e a s and rrlay g e t .the p r o l o n g e d s e t t l e m e n t 1,nsnl;ioned by Mr.. Dalcars.

The wisdom o f u s i n g g r a v e l o r r o c k ;3mSanl:nent~ t>n n e a t

h a s n o t y e t b e e n p r o v e d ~ o n c l u s i v z l y b e c a c s e f f y o u 4 e c i 3 e t o

f l o a t t h e r o a d , s u r e l y d r f e d p e a t i t s e l f ' would b e t h e o b v i o u s

material cut of whLch ", f o r m t h e base. T h f s a p p e a r s 4;o be o n % of ths f'aste1.s cn w h f s h r e s e a r c h i s r e q u f r s d .

Ans%her i n t a ~ e s t f n g ;;.u;nc I s %he w a t e r c o n t e n t o f t h e

r y 2 3 a t end i t s e f f e c t on t h e t y p e of c o n a t r u c t . f o n . For e x ~ r a p l e , f t .would b e u s e f i l l t o know how ?;ha m o i s t u r e c o n t e ~ i t tinder t>e r o a d compares ~ 5 t h t h s t i n t h e a d j o i n j - i ~ g p s a t . The b e l i a v f o ~ r

and e f f e c t a f w a t , e r i r - p e a t would p r o ~ ~ i d e anothezz u s a f ' d s1d3 Jec?.t

f o r resear.c.h.

The l a s t p o i n t f s a b o u t f'fbroiis p e a t whl-ch O C C U I ~ ~ l.i? somi: a r e a s . T h l s s o r t o f p e a t may p a r t i a l l y d r y o u t s n d i t w i l l t h e n c s n t ~ f n a p r o p o r t i o n o r a i r a n d w f l l bacorne q u i t e ~ l . n s u L t a b l e

f c r c a r r . y P . 3 ~ a n y form o f c o n s t r i ; i c t i c n , I n some place::j a ve-ry

c l o s e f f b r o u s p e a 5 o c c u r s and t h i s SeeIris te b e t h e b e s t one t o

. ~ i , 3 2 f ~ ) r m a t s . T h e r e 9 s t h u s a p r o b : l e m In d e c f d i n g what soubt o f

p s a t e x f s t s on a s f t e and i n w h a t way i t c a n b e expectec-i t o b e h a v s , D r . Lee In s u m f n g up s a l d t h a t t h e r e ? s c s r t a i n l y no l a c k o f p r o b l e ~ s o n c o n s t r u c t f o n over p e e t e n d i z $ 3 a s u b j e c t of

g r e a t f m p o r t a n c e , and ile t h ~ u g h t M r . D r y b u r g h a n d P k . McKillnp

aad t h e d1sc:ussion had i n d i c a t e d p r e t t y c l e a r l y t h a l i n e % . h ~ i ; I n v e s t f g a t i o n s s h o ~ l d t a k e .

A w r i t t e n communization 011 Road C o n s t r u c t i o n o v e r P e a t

r e c e f v e d f r o m J . A . Shak-, B.Sc., M.I.Mun.E., ( C o u n t v S u r v s v o r of Ross and C r o m a r t v )

My f i r s t e x p e r i e n c e w i t h p s a t w a s durfrlg t h e c;onst;ractl.crj. o f t h e G l ~ s g s w

-

E d i n b u r g h Road bet-weer?. 1 9 2 4 and

1930,

At, a rj? L .- i.:" -. -

a b o u t a m i l e w e s t o f Dezhmont V f l l a g e 3.n l i e s t L u t h i a n the ,-:e.tJ

c o n c r e t e c a r r i a g e w a y o n t h e N o r t h s i d e or t h e r c a Z w a s over. a s c f t p e a t bog. The S a u t h s f d e crf t h e c o r l c r e t e slcihu whfch was 3(j -?oet. wlde w a s o v e r khat, h a d b e e n t h e o l d m e t a l l e d c a r r i , ~ s e r , t a g . . The

b e 13 o r

14

f e e t d e e p and f t was d e c i d e d t o d r a i r i 4 t , Thls w e s d c n e Sg mean3 c f R d e s p t r e n c h e x c a v a t e d down t o t h a hard? (3n w h f c h

an

q e n - . ~ c f n t e d 1 5 - i n c h p i p e W R S l a i d , c o n n e c t e d t o a

s u l t . a b l e o u t f a l l . The kraench w a s a f t e r w a r d s f i l l e d . t o ,the surf ::ice

w i t h l a r g e b r o k e n stcne , Tne c o n c r e t e slab was ; . o l l s f . ~ ; l s t e d ~ r . [ - - ~ - d I. a

weeks a f t e r w a r d s m d after t h e r o a d was o p e n t o turcif:?ic t h e s l a b s t a r t e d t o t i l t a l c n g i t s N o r t h e d g e , T h i s t i l t i n g was n o t v e ~ y

n c t i c e a b i e i n t h e s l a b I t s e l f a s t h e road a t t h i s p l a c e w 2 s lor1 a a u p s r e l e i r a t e d c u r v e a n d t h e t T P t i n g n e r . a l y a s c o , n t u a t e d t h e

s u p s r ~ 1 e v a t i c n . L e v e l s were t a k e n s t r e g u l a r p e r l o d s a n d a f ' t e r ssme mc-n%hs t h e ~ u b s i d e n ~ e r e a ? . h e d a maximum o f

8

incrheu and t h e n seemed -i;c S C ! P ~ . T h 3 ;ras i n t h e g r a d i n g was v e r y n o t i c e e ' u l e f n t h e k e r > b = - l i n e w h i c h w a ' s a I r ~ t e r w a r d s r e - g r a d e d . The c o n c r e t e r o a d was subseqt:en;;ly c.e.versd wP-Ch 2 i n c h e s o f a s p l i a i t ,

It.

may b e p o s s f b l e t r : I 6 : ; a t e +:.his s e - , t i . o n a n d f i ~ d o u t from t l i e l a c a l

D i s t r i c t , Road S ; l r v e y c r - a t B a t h g a t e kA-,i.u :he r o a d h a s b e h a v e d s i n c e ~ b o u . 5 1 9 3 0 ,

In

1930

I was s s k e d t c e x p r e s s a n o p f n i c n a s t o w h a t mfgilL, b e done t o A c s . c n e r e t e m a d i n t h e N o r t h e r n District of K i r k o u d b r f g h t s h f r e w h i c h h a d b e e n c ~ i ; . s t r u e t e d a b c u t two y e a r s p1.e-vioclsly on t o p o f an e x i s t i r i g m a d , It seemed that b e f o r e t h e

~ ; o n s r e t e r c a d W A S l a f d , o r n;aybs d i r r f n g the c o u r s e c f c . , o ~ i s . t ; r u c t l o n , d f t l c h e s j - t c

4

f e e t d e e p h a d b e e n d u g a i e n g t h e e d g e d fntc t h e

pea.t. T h e s e t r e n c h e s w e r e b a d l y g r a d e d arid d i d n o t g o dcwn t c thn, h a r d , and i n s c r c s p.'i.a2eu h a d p a r t l j ; ' f a l l e n rin. D ~ r f n g d r y weathaii f , h e ~ e was P:?#tIg C i no w a t e r in t h e s e d f t c h e s b u t i n we!:. we at he^

t h e y were f u l l t c t h e t e p , T h e f l u e . t u a t f c n s i n t h e w a t e r l e v e l . a f f e c k e d She p e a t barik c;n whPch -the cad was c o n s t r d c t s d , G u ~ f n g d r y weat,hela t h s p e a t ; seerned t;c ,3hr.9irk9 b u t n e v e r d r i e d o u t

c o ~ p l e t e l y , I n wet; w e a t h e r , a f , L e r a p r o l o n g e d d r y s p e l l , t h e ~ ; e z t : m d e r t h e r c a d seemed t o swe'i,.sl and t h e c o n c r e t e s l n b a t t h e

t r a n s v e r s e j i i l n t s vowed v e r y d e f i n i t e l y , T h i s m o v e n e n l w a s i l - r e s u ' f a r and scmeti.mes t h e s l a b cn o n e s i d e o f h joint r o s e

a b c u t a n insh above t h e s l a b on t h e o t h e r s f d e . The e d g e s o r t h e j o f n t s h a d i n ccnsequ'er,ce becsrne b a d l y b r o k e n w i t h t h e i ? ~ p s r ; t o f t r a f f i c an% n.i: ea;;h j c i n t ; t h e r e was b a d l y s h a t t e r e d c o n c r e t e r f g h t a c r o s s t h s r z a d , There w e r e raa:.(y o t h e r c r a c k s t h r o q 1 i ; l o u t t.he

c o n c r e t e : s l a b w h i c h .iiJere probab1;y due t o t h e way f n w l ~ i e h t h e s l a b

liad b e e n constructed o n t o p o f t h e e x i s t i n g r o a d , I t ssemcd t h a t

i n s u f f i c i e n t a t t e n t f u n h a d been g i v e n t o g r a d i n g t h e c l d rpcad

b e i ' c r e l a y f n g t h e c o n c r e t e , The t o p c f tkie concrste h8.d c b v i o u s l y b e e n l a i d t o a mcre r e g u l a r s u r f a c e t h a n t h e o l d .cad m d I s u s p e c t t h a t , t h e c a n c r e t e s l a b v a r i e d i n t h f c k n e s s , I t was al.so s e v e r 8 1 f e e t w i d e r than t h e o l d c a r r i a g e w a y and e x t e n d s d heyorid I t -,-.

e i t h e r o n o n e s i d e o r t h e o t h e r by s e v e r a l f e e t t o ~ i v e an f m p r g v e d

alignment, It was t h e r e f o r 2 d i f f i c u l t t o a t t r f b u t e a l l t h e c r a c k i n g t o movement cf t h a F e a t . UPtfma+,ely I recocnmendsd the^

t h e e o r l c r e t , e s l a b b e r c l l e d t e d e s t r u c t i o n , This w a s dc;;le w t t k 3 h e a v y t r a c t i o n e n g i n e , The r o a d w a s a f t ; e r t s a ~ d a r a e g a l . ~ t e c ! and

s u r f a c e d w i t h t s r m a c a d a m , 4li;hough t h e r e was some u ~ : . i ~ ~ I . a t i o ; r l l"r'3~ t i m e t c tfme Lhe, running s u r f a c e r s n l a i n e d ?;.;cod,

About

1933/34

t h e o l d g r a v e l r ~ a d rrom Ringf o r d t c N e w G ~ l i o w a y f n K f r k c u d b r i g h t s h i r e was b e f n g improved b y

s ' t r e n g t h e n i n g , ~ - + e g u l a t i n g and s:nf a c i n g i n termac. .t! t one

p l a c e t h e r o a d p a s s e d o v e r a p a c k s t o f p e a t whfch was p r o 3 3 d

Lo a. d e p t h o f o v e r 20 fes.';, T h i s e x t e n d e d f o r a b o u t 190 y a r d s , No a t t e v p t was made t o d ~ a i n Lhis peaJ;; b u t s h a l l o w d i t c h e s

wez-e dug t o g e t r i d o f s u r f a c e w a t e ~ . The e x i s t f i i g r o a d . , t13out 1 2 f e e t wfde, w e s b e i n g widened t o 15/16 f e e t . The t~il-f al.ong t h e e d g e s o n t o p of +,he p e a t w a s l e f t ur~df s t u r b e d and t h e r c a d s ~ ~ e n g t h e n e d with :re jsctvs and s m a l l m e t a l , t h e s t r e n g t h e n i n g b e i n g c a r r i e d about

9

i n c h e s b e y ~ n d t h e edge of t n e c e ~ r - i a g e w a y on e a c h s i d e , The p ~ ; ~ t under t h e r o a d was very s o f t a l i l t h o o l d ~ o a d s u r f a c s moved quite p e r c e p t i b l y u n d e r even a l i g h t l c a d . Twc c o a t s of tarmac each. about

3

inc;hes t h i c k were l a f d on t o p of t h e s t r e n g t h e n i n g ; t h e s t r e n g t h e n i n g p r o b a b l y v a r f e d from

a b o u t

6

i n c h e s i n t h e wheel .tlaa~qCs to a b o u t

3

f n c h e s i n t h e centr8e

cf' t h e ~ o a b , 'Thq two c o a t s c f tarmacadam seemed t o g f v e t h e

d e s i r e d r e s u l t and aXi:haxgh t h e r e w a s a c e r t a i n amount of u n d u l a t i o n t h e r e was no undue d l s t r z ~ t ; f o n o r A b r e a k i n g up of t h o s u r r a c e .

1943-53: For t h e p a s t 1 0 y e a r s

T

have, b s e n g i v e n many opporbuni- t i e s f o r watchii-;g t h e b e h a c i o u r of p e a t , b o ~ h on the Main-land and on t h e I s l a n d of Lewis. I n Lewis i t h a s been t h e p r a c t f c e i n t h e p a s . t +,q d i g p e a t f c r r.ight up t o w f t h f n a few f e e t o r ' t h e

e d g s 'of a r e a d . The r e s u l t i s t h a t i n many p l a c e s r o a d s a r e now bsing s a r ~ i e d Gn what T c o k l l ~ o p a a 5 ernbenkments, o v e r what i s i o c s l l y termed " s k f n n d

and"

fliorn which p e a t has been remcved r i g h t dcwn t o ths a n d e r - ; l g f n g c l a y or.. grgavel. These r o a d

e-abanlxment.8 a r e p r a c t f c a l i y f r w o s s f b l e ts m a f n t a i n and I ' t seems t o .me t h a t i n t h e s c u r s s o f y e a r s t h e v w l l ' i g r a d ~ a l i y w i t h e r away. The o u t e r edges cP' t h e s e banks brae g r a d u a l l y m o u l d e r i n g and a r e s u b j e c t e d t o 2,11 bhe - ~ a g a ? l e s of t h e Lewfs c l i m a t e . During s p e l l s of d r y w e h k h e ~ I t is q i l f t e r s t f c 6 a b l e t h a t t h e p e a t J.3 a c t u a l l y b e i n g blolsn away i n th3 f ' c m cf+ dust,.

A t 5he M 6 c A ~ ' i a y Fle s e a r c h S t a t i o n n e s r S t o ~ n o w a y e x p e r l -

merit.; w e r e caxar.fed ou.<; many y s a r s ago ry;n t h e c u l t i - r a t f u n o f p e a t l a n d . P a r ' t o f 'theae e x p e r f m e n t s consisted (3F e x t e r i s f ve d r a f n a g a

by- maans o f a g ~ i c u l t ; u r a l t 4 1 e p i p e s 2 feet t o 2 f e e t 6 Fliches

below the slirfar;e. I n many p1ac:es t o d a y t h e s e . t i l e p l p e s a r e o n l y a rnatt;ep of i n c h e s below t h e s a r f a c e , and 1 b e l i e v e i n some p l a c e s they a r e expnsed.

From t h e f c r e g o f n g experfarice o v e r t h e l a s t 25 y e a r s

I have ccme t o t h e e o n s l u s l . ~ n t h a t 1 % i s b e t t e r i n rwad z o n s t r u o t i o n n o t t o d r a i n p e a t , and if s f d e d i t c h e s a r e n e c e s s a r y f o r s : ~ r f a c e d r a f n a g e t h e y s h o u l d be a s s h a l l o w a @ p o s s i b l e . A s Long a?! t h e waterb con5ent i n t h e peat: r e m a f n s h i g h and f a i r l y c c n s t a n t and

t h e r e i s a sr.a.bst;antial b u t rao.t t o o r P g f d s u r f a c s en t h e r o a d r e m a i n s f a i r l y .gi.cci. I f , bcrg!e-wsr, t h e p e a t f s d r a i n e d o r ever1 p a r t l y d r i e s out.. d u r i n g a l o n g 311y summar, weak s p a t s very soon

show up a s .+-.he u n d e r l y i n g

eat

may v a r y q u i t e c o n s i d e r a b l y I n 5 3 t h I t s c o m p o s f t i o n and d e p t h and t h e r e is u n 3 q u ~ l s s t t ; i e m e n t .