OPTIMALIZATION OF BLASTING IN »LAKOVIĆI« LIMESTONE QUARRY

Optimalizacijom miniranja uz zaokrctanje fronte kamenoloma za oko 20º ostvarivanje takvog granulometrijskog sastava minirane mase da natgabaritnih blokova bude ispod 1 %, troškovi bušačko-minerskih radova za pridobivanje istih količina kamena smanjiti će se približno na polovinu. Optimalizacija je provedena nakon detaljnog snimanja diskontinuiteta u stijenskoj masi, njihove i statističke obrade te eksperimentalnog određivanja veličine linije najmanjeg otpora u samom kamenolomuThe optimalization of exploitation in »Lakovići« limestone quarry is described. Based on determined discontinuities in the rock mass and their densities, the best possible working site have been located in order to obtain the best possible sizes of blasted rocks and work slope stability. Optimal lowest resistance line size for the quarry has been counted and proved experimentally. New blasting parameters have resulted in considerable saving of drilling and explosive

Influence of the Tectonic Fabric on the Open Pit Desing in the ¨Zaprešički Ivanec¨ near Zagreb Dolomite Quarry

U kamenolomu dolomita »Zaprešički Ivanec« kraj Zagreba odvija se eksploatacija u sklada s podacima dobivenim analizom tektonskog sklopa, određivanja brzina uzdužnih valova metodom refrekcijske seizmike i mjerenjima seizmičkih efekata izazvanih miniranjem. Izraženi su osnovni podaci iz analize tektonskog sklopa i drugih mjerenja na osnovu kojih je definiran položaj otkopne fronte i određeni optimalni uvjeti miniranja. Rezultati dugogodišnje eksploatacije u kamenolomu verificiraju takav kompleksan pristup razradi ležišta i projektiranju eksploatacije.In the »Zaprešički Ivanec« dolomite open pit near Zagreb, exploitation is carried out according to data obtained by analysis of the tectonic fabric of the rock massif, by measurement of the longitudinal seismic waves velocity, and effects of the seismic waves provoked blasting. In this article the fundamental data obtained by structural analysis and measurements with their influence on the pit design and the optimization of blasting conditions, are reviewed. Results of the longtime exploitation verify such complex aproach to deposit work-out

ENGINEERING GEOLOGICAL CHARACTERISTICS OF THE ROAD SOLIN - KLIS (DALMATIA, CROATIA)

Istraživanjima u »intaktnom« terenu, kao i na izvedenim kosinama usjeka i zasjeka, u temeljnim jamama objekata i u tunelima, određene su inženjerskogeološke i osnovne tektonske značajke senonskih vapnenaca, eocenskog fliša, prominskih breča i brečo-konglomerata, te oligocenskih slabo sortiranih breča, na trasi poluautoceste Solin-Klis (Dalmacija, Hrvatska). Laboratorijskim ispitivanjima na velikom broju uzoraka stijena utvrđeni su rasponi njihovih osnovnih fizikalnih i mehaničkih značajki unutar pojedinih inženjerskogeoloških cjelina. Rezultati laboratorijskih ispitivanja uspoređeni su sa svojstvima stijenskih masa u cjelini procijenjenim primjenom RMR-klasiflkacije stijena i rezultata mjerenja brzine širenja uzdužnih seizmičkih valova. Ukazano je na mogući istovjetan pristup i kod izrade Osnovne inženjerskogeološke karte Republike Hrvatske.The research, that has been done both on the »intact« terrain and on the opened cuts and discontinuities, and which has been carried on in the basic caves of the object, as well as in the tunnels; has verified the engineering geological and basic tectonic characteristics of Senonian limestones, Eocene flysch, the Promina breccias and breccia-conglomerates, as well as Oligocene poorly sorted breccias, on the route of semi-highway Solin-Klis (Dalmatia, Croatia). The lab analyses, of the great number of the rock samples, have brought out the parametres of their basic physical and mechanical features within a particular engineering geological unit. The results, thus obtained, have been compared to the qualities of the rock structure block as a whole, and had been previously evaluated by applying RMR-classification of the rocks, and the results of the measured velocities of the longitudinal waves. It has been pointed out that similar procedure may be applied in the publication of General Engineering Geological Map of the Republic of Croatia

POTENTIALLY UNSTABLE SLOPE ABOVE ORE PROCESSING PLANT IN THE "OČURA" DOLOMITE QUARRY (LEPOGLAVA, NORTH CROATIA)

U radu su prikazani rezultati kompleksnih inženjerskogeoloških istraživanja provedenih na uvjetno stabilnoj kosini iznad separacije kamenoloma »Očura« kraj Lepoglave. Snimanjem elemenata tektonskog sklopa i obradom dobivenih podataka određeni su diskon-tinuiteti referentni za stabilnost kosine na ravni i klinasti lom. Mjerenjem veličina stijenskih fragmenata duž kosine, prirodno odvojenih diskontinuitetima, nastojalo se ocijeniti vjerojatne brzine Širenja uzdužnih seizmičkih valova, koje su korelirane s brzinama određenim metodom plitke refrakcijske seizmike. Na osnovu brzina Širenja seizmičkih valova i »RMR«-klasifikacije, procijenjena su fizičko-mehanička svojstva stijenske mase. Dobiveni rezultati ukazuju na to da se kosina iznad separacije u kamenolomu »Očura« mora smatrati uvjetno stabilnom, s realnom perspektivom da će potresni valovi nastali miniranjem tijekom planirane eksploatacije u zaleđu kosine, dovesti do dinamičkih promjena, otvaranja sada zatvorenih diskontinuiteta i obrušavanja velikih blokova koji se nalaze iznad diskontinuiteta.The complex engineering investigation, in the nearest surroun-dig of the conditionally stable high slope, close to ore processing facilities in the dolomite quarry »Očura« near Lepoglava (North Croatia), was carried out. Studying the tectonic features of the rock mass, discontinuities referent to the slope stability, was found out. Rock fragment size was measured and data processed using statistical design. According to rock fragment mean values, velocity of the longitudinal seismic waves was predicted. This values was compared with velocities of the longitudinal seismic waves, determined using gcophisical refraction seismic method. Physical and mechanical properties of the dolomite rock mass, considering longitudinal and transversal seismic wave velocities, and »RMR«-classification was assesed. All the results indicate, that the slope above the ore processing facilities should be consider as conditionally stable, with real probability to get unstable under the vibrations caused by blasting, during the exploitation in the field, close behind the investigated slope

POTENTIALLY UNSTABLE SLOPE ABOVE ORE PROCESSING PLANT IN THE "OČURA" DOLOMITE QUARRY (LEPOGLAVA, NORTH CROATIA)

U radu su prikazani rezultati kompleksnih inženjerskogeoloških istraživanja provedenih na uvjetno stabilnoj kosini iznad separacije kamenoloma »Očura« kraj Lepoglave. Snimanjem elemenata tektonskog sklopa i obradom dobivenih podataka određeni su diskon-tinuiteti referentni za stabilnost kosine na ravni i klinasti lom. Mjerenjem veličina stijenskih fragmenata duž kosine, prirodno odvojenih diskontinuitetima, nastojalo se ocijeniti vjerojatne brzine Širenja uzdužnih seizmičkih valova, koje su korelirane s brzinama određenim metodom plitke refrakcijske seizmike. Na osnovu brzina Širenja seizmičkih valova i »RMR«-klasifikacije, procijenjena su fizičko-mehanička svojstva stijenske mase. Dobiveni rezultati ukazuju na to da se kosina iznad separacije u kamenolomu »Očura« mora smatrati uvjetno stabilnom, s realnom perspektivom da će potresni valovi nastali miniranjem tijekom planirane eksploatacije u zaleđu kosine, dovesti do dinamičkih promjena, otvaranja sada zatvorenih diskontinuiteta i obrušavanja velikih blokova koji se nalaze iznad diskontinuiteta.The complex engineering investigation, in the nearest surroun-dig of the conditionally stable high slope, close to ore processing facilities in the dolomite quarry »Očura« near Lepoglava (North Croatia), was carried out. Studying the tectonic features of the rock mass, discontinuities referent to the slope stability, was found out. Rock fragment size was measured and data processed using statistical design. According to rock fragment mean values, velocity of the longitudinal seismic waves was predicted. This values was compared with velocities of the longitudinal seismic waves, determined using gcophisical refraction seismic method. Physical and mechanical properties of the dolomite rock mass, considering longitudinal and transversal seismic wave velocities, and »RMR«-classification was assesed. All the results indicate, that the slope above the ore processing facilities should be consider as conditionally stable, with real probability to get unstable under the vibrations caused by blasting, during the exploitation in the field, close behind the investigated slope

ENGINEERING GEOLOGICAL AND STRUCTURAL GEOLOGICAL CHARACTERISTICS USED TO PROVE THE STABILITY OF HIGH CUTS IN COMPACT ROCKS ON THE ROAD MC-11, SOLIN-KLIS

Opisane su inženjerskogeološke značajke stijena, nužne kao podloga za računanje i dokaz stabilnosti visokih zasjeka u čvrstim razlomljenim stijenama. Mjerenjem i analizom pukotinskih sustava, dobijeni su podaci za strukturno-geološku obradu. Uz pretpostavljeni i simulirani ravni lom utvrđen je nagib s kojim bi kosine zasjeka bile stabilne.The paper deals with the engineering geological characteristics of the rock massif in charge to compute and provide the stability of high cuts in solid fractured rocks. The data for the structural geological processing have been obtained by measuring and analyzing the system of fissures. In addition to the supposed and simulated straight fracture the maximum slope of the high cut has been determined considering additional forces which were introduced into the rock mass

INFLUENCE OF THE TECTONIC FABRIC ON THE OPEN PIT DESING IN THE ¨ZAPREŠIČKI IVANEC¨ NEAR ZAGREB DOLOMITE QUARRY

In the »Zaprešički Ivanec« dolomite open pit near Zagreb, exploitation is carried out according to data obtained by analysis of the tectonic fabric of the rock massif, by measurement of the longitudinal seismic waves velocity, and effects of the seismic waves provoked blasting. In this article the fundamental data obtained by structural analysis and measurements with their influence on the pit design and the optimization of blasting conditions, are reviewed. Results of the longtime exploitation verify such complex aproach to deposit work-out (the paper is published in Croatian)

ENGINEERING GEOLOGICAL CHARACTERISTICS OF THE ROAD SOLIN - KLIS (DALMATIA, CROATIA)

The research, that has been done both on the »intact« terrain and on the opened cuts and discontinuities, and which has been carried on in the basic caves of the object, as well as in the tunnels; has verified the engineering geological and basic tectonic characteristics of Senonian limestones, Eocene flysch, the Promina breccias and breccia-conglomerates, as well as Oligocene poorly sorted breccias, on the route of semi-highway Solin-Klis (Dalmatia, Croatia). The lab analyses, of the great number of the rock samples, have brought out the parametres of their basic physical and mechanical features within a particular engineering geological unit. The results, thus obtained, have been compared to the qualities of the rock structure block as a whole, and had been previously evaluated by applying RMR-classification of the rocks, and the results of the measured velocities of the longitudinal waves. It has been pointed out that similar procedure may be applied in the publication of General Engineering Geological Map of the Republic of Croatia (the paper is published in Croatian)