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o f s 1n a l l d ia m e te r is = lo s e t o o n e o f l a r g r e a te r d ia m e t e r (le ss

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w e r e n s in g le tu n n e l bu l i l l h c t w o a r e c lo sc t o c a c h o lthc r c o no f T u n n e ) s i n So i l s

s t r ui on D ! t l1e s n t a l l O n c c a n b e c x pe a c d t o i n d u c e lo c a l iz e d [a r e a s o f g r e a t e r d e fo r m a t io n a r o u n d t h e l a r ge r Om T hi s w h e n t u n n e ls a r c b u i l t i n o pe n count Ie s s o i m a i e Du i n id e fo r m a 1io n is c s t i n r a t e d n s d o u b le t he o n e t h a i W o u ld be t he c a v i t : : O r m o v e m e n t o f s u r ia : c , v l . . s a ; ' " : " ; · : £ : e T i

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