SPECIFIC ENGINEERING GEOLOGICAL AND GEOTECNICAL PROBLEMS OF DAM CONSTRUCTIONS IN KARST TERRAINS

U radu je, na početku, dan opći prikaz problema izgradnje brana – formiranja akumulacija u krškim terenima, zatim specifičnosti krških terena, specifični inženjerskogeološki problemi i mjerodavni činioci uticaja krškog procesa i njegovih tvorevina na izgradnju brana u njima. Izgradnja brana u krškim terenima predstavlјa poseban problem koji zahtjeva dopunske uvjete u odnosu na uvjete u ostalim terenima, te je zbog toga neophodna posebna opreznost tokom inženjerskogeoloških istraživanja, ali i izgradnje i eksploatacije. U krškim terenima postoje brojni, složeni, raznovrsni pa i specifični inženjerskogeološki problemi, skoro uvijek nešto drugačiji, na svakoj novoj lokaciji, koji se moraju uzeti u obzir pri izgradnji brana. Na kraju rada daju se karakteristični primjeri inženjerskogeološkog rizika izgradnje brana u krškim terenima, iz inozemne i domaće prakse, gdje su sanacioni radovi dali pozitivna rješenja, ali i primjeri gdje ni obimni i dugotrajni sanacioni radovi sa velikim financijskim sredstvima, nisu dali zadovolјavajuće rezultate. Posebna pažnja posvećena je riziku proviranja vode iz akumulacije.The paper first presents a general overview of the problem of dam construction - the formation of reservoirs in karst terrains, followed by the overview of the karst terrains specificities, specificities of engineering geological problems, and the relevant influence factors of the karst process and its forms on dam construction in karst. The construction of dams in karst terrains is a special problem that requires additional conditions in relation to the conditions in other terrains, which is why special care is needed during engineering geological research, as well as construction and operation. There are numerous, complex, diverse and specific engineering geological problems in karst terrains, almost always somewhat different, at each new location, which must be taken into account when constructing dams. Typical examples of the engineering geological risk of constructing dams in karst terrains, from foreign and domestic practices, are presented at the end of this paper, including both, remediation works that have given positive solutions, and cases where extensive and long-term remediation works with high financial resources have not given satisfactory results. Special attention is given to the risk of water seepage from the accumulation