32 Mining Constru C tion 1 2013 Istanbul BO Y ABA T DA M In the Gokirmak V alley along the route of the famous Silk Road one of T urkey s largest dams is soon to be commissioned having eliminated leakages with an innovative drilling and grouting plan C ompleted in 2012 after just four y ears of constr uction the nearl y 200 m high Bo yabat Dam is a record break ing project in T urk e y It is situated in the G o k i r m a k B l u e R i v e r V a l l e y a n d f e a tures a h ydropo w er plant that is e xpected to come online this y ear w hich will signif cantl y reduce the countr y s dependenc y on impor ted ener gy Apar t from being a landmark in itself due to its location along the Silk Road w here the to wn of Bo yabat is kno wn as an ancient trading hub the dam marks a milestone in re gional de v elopment The reser v oir totals 60 000 km 2 in size with an installed capacity at the po w er plant of 513 MW The sheer size and ontime deli v er y are not the onl y achie v ements that mak e this dam remarkab le Among the biggest chal lenges w as ha ving to deal with unpredict ab le seismic rock for mations prone to w ater leakages r einforcing the area The Gokir mak V alle y is situated just 25 km from an acti v e f ault line The area primaril y consist of sedimentar y rock with high seismicity w hich can cause e xcessi v e w ater losses putting the stability of the dam foundations and its ab utments at risk The solution w as lar ge scale reinforce ment F or contractor Do gus Insaat and its subsidiar y A yson sealing and stabilizing the dam became a massi v e under taking as w ell as a race ag ainst the clock W e had to accomplish a big project in a v er y shor t time and t ha t s w h y our needs ha d to be fulflled immediatel y sa ys Cumhur T ezel Project Manager Do gus Insaat T ur ning to its supplier Atlas Copco an e xtensi v e drilling and g routing plan w as initiated More than 210 km of injection holes w ould be drilled e xtending out from both sides of the dam using 12 Diamec U6 PHC core drilling rigs equipped with the NO 2 wireline core drilling system The holes w ere drilled from three g aller y le v els w here core drilling made it easy to continuousl y anal yze the quality of the rock through per meability tests Although the SC 68 matrix diamond core bits that w ere used had an a v erage lifelength of 1 000 m one cre w member achie v ed an astonishing record of 4 350 m using a single bit Ha ving drilled an a v erage of 400 m per da y or about tw o meters per hour the com pleted holes w ere then injected with more than 33 000 m of g rout f l l i n g c r a c k s a n d fssures to pro vide rock solid stability Joint venture for grouting In addition to the feet of Diamec rigs on s i t e A tl a s C op c o p r o po s e d a n i n no v a t i v e modular g routing setup This w ould consist of tw o central g routing stations installed on both ba nks br inging in the v ers atile s ystem Unig rout Smar t A Six Unig rout Smar tA22 platfor ms w ere emplo y ed three on each bank In a typical g routing triumph at Boyabat Dam g routing triumph at Boyabat Dam Our needs had to be fulflled immediately as we had to accomplish a very big project in a very short time Cumhur t ezel Project Manager Dogus Insaat All systems go at lef t drilling injec tion holes with the Diamec U6 PHC and right the Unigrout Smar t A controls g athered in one room