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This paper presents an overview of extensive geotechnical, hydrological and geological investigations of soils around the biggest cover-collapse sinkhole opened in the Mečenčani village a week after the Petrinja Mw 6.4 earthquake of December 29, 2020. The geotechnical investigation included two shallow boreholes, Standard Penetration Test (SPT), manually driven Dynamic Probing Light (DPL), and groundwater table observations. In addition, various geotechnical laboratory tests were performed. Obtained data provide the essential geomechanical information necessary for understanding processes associated to sinkhole collapse. Furthermore, it also provides the basis for better preparation and streamlining of future investigations and efforts towards clarification of the failure mechanisms in similar geological settings.

After a MW 6.4 earthquake occurred on December 29, 2020 in Petrinja, Croatia, over 100 cover collapse sinkholes appeared in a small 1 km2 area in a period of several months after the event. In the beginning of 2021, a geotechnical reconnaissance and a limited geotechnical subsurface investigation was performed. The existing geological and hydrogeological data were analysed, and the geometry of sinkholes was recorded. Two geotechnical boreholes, in-situ geotechnical characterization and standard penetration tests were performed close to the biggest sinkhole, followed by a laboratory testing of physical, index and design properties. All the collected data showed that there was a specific geological setting on this microsite. A typical soil profile for the biggest recorded sinkhole was developed and used for the numerical analyses to examine the possible failure mechanisms and to perform the parametric analyses for determining the effects of depth and geometry of the existing underground caves and soil properties on the cover-collapse sinkhole formation.

Management of construction waste that was generated by earthquakes and reconstruction of damaged facilities requires good prior planning of options, as well as good coordination of all institutions during the reconstruction period. The planning should include three main levels: 1 – waste handling in a safe manner, with fast education of persons working on clearing and distribution of means for protection ; 2 – planning of the logistics and temporary storage areas ; 3 – analyses of the shortcomings of the existing legal framework for future waste management in crisis and issue instructions on crisis management of construction and demolition waste. This paper provides an overview of the current crisis management of construction and demolition waste after Zagreb earthquake in March 2020 , identifies challenges with management of such waste, and shows the la test advances in recycling of the problematic streams as an opportunity to advance both, emergency – and usual waste management. In c onclusion it provides recommendations to take following course od actions: 1 - increase of the capacity to recycle, treat and temporarily store construction and demolition waste ; 2 – improve the separation (recycling)process to allow the removal of other wastes and to separate the construction and demolition waste by category ; 3 – focus the activities on research and development of the products from recycled construction and demolition waste (upgrade), especially from the mixed construction and demolition waste ; and 4 – make possible the use of recycled materials in public procurement (including construction and reconstruction of public buildings and infrastructure), prioritise use of construction and demolition waste to stabilize the existing landslides and ground disturbances caused by the earthquakes, facilitate and stimulate the abolition of waste status of materials produced from the construction and demolition waste. Control, separation and/or immobilization of hazardous waste should not be overlooked, as well as the safety of people who handle construction and demolition waste in emergency and afterwards. Legal framework and procedures should be planned and prioritized in advance, thus preventing bottlenecks in communication a nd coordination of regulatory bodies of different levels in the time of emergency.

The December 2020 sequence of earthquakes in Croatia started on 28 December 2020 at 6:28 local time, with a magnitude M5.0 with epicenter near Petrinja. It was followed with a M4.7 at 7:49 and a M4.1 at 7:51, with a series of weaker aftershocks. On 29 December 2020 at 12:19, a M6.4 struck, which was felt in all parts of Croatia and neighboring countries. The sequence continued for 36 days (Croatian Seismological Survey 2021). The most prominent, surprising, and relatively rare geotechnical earthquake effect includes the collapse of numerous sinkholes in the time frame of three months after the main shock.

Laboratorij za mehaniku tla osnovan je 2008. godine na Rudarsko-geološko-naftnom fakultetu Sveučilišta u Zagrebu. Njegova prvotna namjena bila je unaprjeđenje izvođenja praktičnog dijela nastave na studijima rudarstva, geotehnike i inženjerske geologije. Međutim, kontinuiranim opremanjem i uvođenjem novih ispitnih metoda, omogućena je realizacija brojnih znanstvenih i stručnih istraživanja za potrebe domaćih i međunarodnih projekata, istraživanja u svrhu izrade završnih radova i doktorskih disertacija, te istraživanja za potrebe realnog sektora. Iako laboratorij djeluje u okviru Zavoda za rudarstvo i geotehniku, znanstvena i stučna istraživanja provode se za i u suradnji s drugim zavodima RGN fakulteta, te znanstvenim i nastavnim institucijama u zemlji i inozemstvu. U radu će biti opisan razvitak laboratorija od osnutka do danas, prikaz njegove uloge u nastavnim, znanstvenim i stručnim aktivnostima fakulteta, kao i neki rezultati istraživanja provedenih u zadnjih petnaestak godina.

Croatia has a long tradition of dimension stone exploitation, mostly by surface extraction. Lately, the dimension stone has been extracted in the world also by underground methods, because of environmental, organisational and economical reasons. In such a case, stability problems require adequate studies in order to avoid expensive and technologically unacceptable artificial support measures.In the Kanfanar quarry near the town of Pazin on the Istrian peninsula an existing active surface exploitation had to be transferred underground because of economical and environmental constrains. The stability analysis was made by numerical modelling with the finite difference code FLAC. These calculations are described in the paper and represented the first phase of the pillar design.

Construction and demolition waste (C&D waste) is one of the most relevant waste types primarily due to large quantities and a high potential for re-use and recycle. This paper discusses the issues related to C&D waste management in the Republic of Croatia. It presents the overview of legislative changes and its impact on the C&D waste management in Croatia. C&D waste quantities per county in the period from 2001 to 2015 are given as well as the expected C&D waste quantities in the future. It is concluded that the legal framework is well established, but it is not implemented consistently. Therefore, it is necessary to plan certain activities and additional resources in order to make the C&D waste management more efficient. The paper also presents the options of C&D waste recycling and describes the recycling technology in a C&D waste recycling plant in the Republic of Croatia. Taking into account the relatively low price of recycled aggregate, long distance transport is not profitable. It is concluded that the use of mobile treatment facilities would be a good practical solution taking into account the underdeveloped infrastructure for C&D waste management.

In the paper, mineral raw materials and waste management policies of the Republic of Croatia are elaborated and compared to European standards and directives. The origin, composition and quantities of waste are provided together with a current status in waste management. Mineral raw materials production and proven reserves are also listed. Waste and mineral raw materials management is commented from the sustainability point of view. Some conclusions are given for the country with a limited mineral raw material resources and potential use of secondary sources.

Permeability is a measure of the ability of a porous media to transmit fluids. Fluids that flow through porous media can be both in liquid and gaseous form. The movement of fluids occurs due to two major transport mechanisms i.e. advection and diffusion. Hydraulic conductivity of soils is commonly obtained by numerous testing methods that are currently available for laboratory and field measurements, where fluid transport is described by advective flow. However, the aforementioned test methods are not completely appropriate for the gas permeability measurements of soils. There is a growing interest for gas permeability determination mostly for environmental applications but also for geotechnical engineering in general. Besides, gas permeability of geosynthetic clay liners (GCLs) that have been used as hydraulic or gas barriers in many geotechnical and hydrotechnical applications, landfills and liquid waste lagoons for quite a while, is of major importance. Special consideration is given to the large quantities of biogas produced in landfills, which is most prominent in the early stage of a landfill lifetime. GCLs were already recognized as a highly effective hydraulic barrier a long time ago. Lately, there has also been a growing interest in assessing the efficiency of the GCLs as a gas barrier. In this article, the results of previous studies of soil and GCLs gas permeability are summarized at the beginning. It is followed by the description of a modified triaxial cell and gas permeability determination. Also, through the analyses of preliminary test results, the main parameters that affect gas permeability of soils and GCLs are identified.

Geosynthetic clay liners (GCL) are factory- manufactured hydraulic barriers consisting of a mineral (bentonite) and geosynthetic component (geotextile or geomembrane). Over the last several decades, their application has increased intensively in various engineering projects for environmental protection purposes, including landfills. In Croatia, there is also a significant number of landfills with GCL incorporated as an integral part of protective systems, most often as the landfill final cover. Since protective systems have to fulfil their designated function over a longer period of time, usually, laboratory tests of the GCL durability and landfill monitoring are being implemented in order to identify long-term functionality of GCL. This study presents laboratory tests carried out on samples of bentonite clay and GCL that were installed at one real landfill near Zagreb between three and nine years ago. The sampling was carried out at 23 locations in the landfill final cover. Following analyses were performed on collected samples, as well as on reference sample (manufactured bentonite in its original state): pH, electrical conductivity, moisture, colour, index properties (free swell index, water absorption capacity by Enslin-Neff test, fluid loss). Mineralogical and chemical analyses were carried out on 13 samples. Mineralogical analyses of bentonite included detailed XRD clay analysis and cation exchange capacity using the Cu-trien method. Hydraulic conductivity was tested on ten GCL samples. Mineralogical analyses proved that montmorillonite is predominate mineral followed by quartz, K-feldspar, plagioclase, goethite, anatase and micaceous material. CEC ranged from 51.96 meq/100g to 75.47 meq/100g. Index properties for all samples are summarized in table 1. It can be concluded that the properties of all samples were deteriorated with time in comparison to the reference sample test results. Moreover, none of them fulfills the required values according to some recommendations nowadays. However, final conclusions about the influence of the cover layer thickness and the time passed since the installation date cannot be precisely divided yet. Therefore, some additional investigations will be carried out.

Agencija za znanost i visoko obrazovanje osnovana je u Republici Hrvatskoj 2005. godine u skladu sa Zakonom o osiguravanju kvalitete u znanosti i visokom obrazovanju kao neovisna nacionalna agencija. Temeljna zadaća Agencije je skrb o osiguravanju kvalitete znanstvenih ustanova i visokih učilišta u RH, koja se provedbeno ostvaruje kroz nekoliko postupaka: inicijalna akreditacija, reakreditacije institucija, tematsko vrednovanje, vanjska neovisna prosudba sustava za kvalitetu. Reakreditacijom se provjerava zadovoljava li pojedina institucija propisane nužne uvjete i standarde kvalitete i do koje razine. Vanjska prosudba sustava je usmjerena na provjeru sustava za kvalitetu. Određeni broj visokih učilišta pored obvezujućih postupaka osiguravanja kvalitete prema spomenutom Zakonu, uveo je dodatno i sustav upravljanja kvalitetom prema normi ISO 9001 ili proveo međunarodnu akreditaciju, za tehničke studije uobičajeno preko njemačke agencije ASIIN. U članku će biti prikazani različiti postupci vrednovanja u visokom obrazovanju koje provodi AZVO prema propisima u RH, praktična iskustva u provedbi već spomenutih postupaka od strane AZVO-a, međusobni odnos postupaka provjere kvalitete kojega provode različite institucije (AZVO, ASIIN), te kritički osvrt na osiguravanje potrebnih resursa kao nužnog preduvjeta za uspješno uvođenje i održavanje sustava osiguravanja kvalitete na visokim učilištima.

Engineered barrier systems (EBS) used in radioactive waste disposal facilities are part of the system which must prevent radionuclide from reaching the biosphere, for up to 1 000 000 years, migrating from deep (more than 300 m), stable geological environment. EBS is the second ‘line of defense’ against the migration of radionuclides, after the corrosion of containers. They also shield containers from possible environmental impact and the host rock from the heat released by the high level radioactive waste (HLW) and/or spent nuclear fuel (SF). Engineered barrier systems are usually made of cement, salt, clay (bentonite) or clay/rock mixtures. Quality control tests of clays are the same for all engineered barrier systems either used in the environmental engineering or standard geotechnical constructions. Differences may show up in the special required criteria related to specific application. Recommended clay properties depend also on the type of host rocks. Standard quality control procedures for bentonite used as a sealing barrier in radioactive waste disposal sites are described as some personal experiences. The research to determine correlation between mechanical properties of the bentonite and its swelling behavior was conducted on the granular bentonite. X-ray powder diffraction showed that the bentonitne contains 80-85% of montmorillonite. Bentonite properties were as follows: liquid limit 437%, plastic limit 53%, specific surface area 700 m2/g and CEC 89 meq/100g. The influence of swelling on the bentonitne shear strength was studied in the direct shear device. During this process, hydration times (7 to 21 days) were changed in a series of tests at different normal stresses (50 to 200 kPa) simulating bentonite clay swelling. The impact of swelling on the bentonitne consolidation and hydraulic properties were studied in oedometer device and triaxial device under isotropic compression conditions. Demineralized water was used as the test fluid. Primary swelling phase was reached after 31 days regardless of the intensity of the normal stress. Shear tests show a significant reduction in cohesion with the extension of the hydration of bentonite, and the friction angle increases with hydration. There is no significant change in the value of the friction angle by extending hydration after 14 days.

Podzemna eksploatacija blokova arhitektonsko-građevnog kamena u posljednje se vrijeme sve vise širi zbog tri glavna razloga: ekonomskog, tehnološkog i ekološkog, a osim toga podzemni otvori mogu se naknadno uporabiti za mnoge svrhe. Podzemna se eksploatacija razlikuje od površinske samo u početnoj fazi vađenja gornjeg sloja odnosno etaže. Naredne se etaže izvode kao i pri površinskoj eksploataciji. U podzemnim rudnicima kamena problemi stabilnosti zahtijevaju odgovarajuće studije kako bi se izbjegli skupi radovi na podgrađivanju. Izložene su numeričke analize jednog podzemnog rudnika arhitektonsko-građevnog kamena, načinjene uporabom programa FLAC baziranog na metodi konačnih diferencija., Underground exploitation of dimension stone is spreading lately for three main reasons; economy, organisation and environment. Moreover, underground openings can be used for many purposes. Underground exploitation is different from surface quarrying only in the first stage, the removal of top slice, descending slices are worked as in conventional quarries. In underground stone quarries, stability problems require adequate studies in order to avoid expensive artificial support measures, The article presents numerical analyses of an underground stone quarry made using of the finite difference code FLAC.

The Faculty of Mining, Geology and Petroleum Engineering of the University of Zagreb is the only higher education institution in Croatia in the fields of mining and petroleum engineering, and one of two institutions in the field of geology. Bologna process was introduced into Croatian higher education system in 2005. New study programmes were created by combining experiences from some leading European universities and by taking into account some peculiarities of the Croatian educational system and labour market. Besides that, substantial effort was made to solve some problems like insufficient attractiveness of our study programmes, high drop-out rate etc. In recent years we have also faced the introduction of quality assurance into the higher education and scientific research. After almost a decade since the beginning of a Bologna process, we have made a thorough analysis of its implementation and recognized some new trends and challenges.

Nagibni stol je laboratorijski uređaj pomoću kojega se na jednostavan i brz način mogu provoditi ispitivanja uzoraka tla, stijena i drugih materijala poput geosintetika radi određivanja kontaktnog kuta trenja pri malim normalnim naprezanjima. Prednosti ovog uređaja u odnosu na upotrebu uređaja za izravni posmik su: preciznije nanošenje malih vrijednosti normalnih naprezanja, manji utjecaj uređaja na izmjereni kut trenja te mogućnost ostvarivanja većih pomaka a time i utvrđivanja rezidualnog kuta trenja. Uređaj se sastoji od ploče na koju se postavlja uzorak, stalka i mehanizma za podizanje ploče. Ploča je na jednoj strani pričvršćena za podlogu, dok je njezina nasuprotna strana slobodna. Na ploču se, dok se nalazi u horizontalnom položaju polaže uzorak, nakon čega se ona podiže kontinuiranom brzinom sve dok uzorak ne klizne a nakon što se ostvari unaprijed određeni pomak bilježi se kut nagiba ploče. Kontaktni kut trenja ovisi o vrsti materijala i hrapavosti dodirnih površina. U ovom radu prikazani su preliminarni rezultati istraživanja u kojima je nagibni stol poslužio za određivanje kuta trenja između različitih geosintetika: geomembrana, tkani i netkani geotekstil te geomreža. Cilj ovog istraživanja bio je izraditi prototip nagibnog stola, razraditi proceduru pripreme i provedbe pokusa koja nije normirana te provesti probna ispitivanja, analizirati rezultate i dati eventualne preporuke za poboljšanje uređaja. Rezultati ukazuju da se na izrađenom uređaju i uz primjenu opisanih procedura dobivaju relevantni podaci o kontaktnim kutovima trenja obzirom da su pokazali dobra poklapanja s ranije objavljenim literaturnim podacima.

Safe long-term management of high level radioactive waste and spent fuel represents one of the most important issues of the modern world. One of the key elements in all modern national radwaste disposal programmes is underground facility in which characterization, testing, and technology development will be carried out. Such facilities are known as underground research laboratories (URLs), and are necessary to provide scientific and technical information as well as practical experience. Croatia is in urgent need of restarting repository development programme. One of the most important elements in that endeavor is URL, which can be easily designed and constructed considering experience of Croatian experts in construction of underground spaces.

Nuklearna elektrana Krško (NEK) ima dozvolu za rad do 2023. godine, a prema postojećim sporazumima između Republike Hrvatske i Republike Slovenije, svaka država je dužna zbrinuti polovinu radioaktivnog otpada nastalog tijekom rada i nakon razgradnje NEK. Sigurno trajno zbrinjavanje visokoradioaktivnog otpada i istrošenog goriva predstavlja jedan od najvećih problema suvremene civilizacije. Najbolji način za dokazivanje sigurnosti odlagališta, što ujedno predstavlja i najvažniji argument u procesu ovlašćivanja budućeg odlagališta, jest razvijen podzemni istraživački laboratorij (PIL). PIL otvoren za međunarodnu suradnju i istraživanja bi sigurno unaprijedio međunarodnu prepoznatljivost i kredibilitet hrvatskog programa za gospodarenje radioaktivnim otpadom, jednako kao i razmjenu rezultata znanstvenih istraživanja široj znanstvenoj zajednici.

U članku se problematizira pitanje proizvodnje energije iz nuklearnih izvora razmatrajući sve veću potrebu za energijom u svjetskim razmjerima, te prednosti i nedostatke korištenja nuklearne energije. Međunarodna agencija za atomsku energiju (IAEA) promovira miroljubivu uporabu nuklearne energije, a Državni zavod za radiološku i nuklearnu sigurnost (DZNRS) nadzire uporabu izvora ionizirajućeg zračenja u Republici Hrvatskoj. Opisana je uloga programa tehničke suradnje IAEA u kojima sudjeluje i RH, a detaljnije je prikazan program pod nazivom INT9173 "Training in Radioactive Waste Disposal Technologies in Underground Research Facilities - URFs". Značaj uključenosti hrvatskih znanstvenika i eksperata u navedenom projektu tehničke suradnje iz područja gospodarenja radioaktivnim otpadom prikazan je kroz aktivnosti provedene tijekom razdoblja od 2009. godine do danas, uzimajući u vidu obveze RH vezano za zbrinjavanje radioaktivnog otpada nastalog radom NE Krško.

U radu je opisan razvoj kolegija i nastavnih programa u području geotehnike i inženjerstva okoliša na RGN fakultetu. Također, kronološki su prikazana znanstvena istraživanja u ta dva područja te sumirani publicirani radovi.

Inženjerske barijere prisutne su u odlagalištima radioaktivnog otpada kako bi se osigurala bolja izolacija te zaštita ljudi i biosfere od opasnog ionizirajućeg zračenja radioaktivnog otpada. Funkcija brtvljenja osigurava se uglavnom upotrebom cementa ili gline (bentonita). Kontrola kvalitete gline provodi se postupcima uobičajenim za ispitivanje materijala koji se ugrađuju u brtvene barijere bilo kojeg inženjerskog zahvata. Jedina je razlika u kriterijima koje glina mora zadovoljiti. Propisana svojstva glina ovise također i o vrsti matične stijene. U članku su opisana svjetska iskustva u zbrinjavanju različitih vrsta radioaktivnog otpada. Detaljnije su opisani standardni postupci kontrole kvalitete bentonitih glina koje se koriste kao brtvene barijere u odlagalištima radioaktivnog otpada, te neka vlastita iskustva i rezultati ispitivanja u provedbi postupaka za određivanje indeksnih pokazatelja (indeks slobodnog bubrenja, kapacitet upijanja vode, granice plastičnosti) te ispitivanja hidrauličke propusnosti bentonita.

Polazi se od toga da je za kvantitativni opis ponašanja ekspanzivnog tla nužno odrediti njegove hidrauličke značajke: krivulje retencije vode i promjene volumena te funkciju hidrauličke provodljivosti. Opisani su eksperimentalni i analitički postupci kojima su te karakteristike istraživanog tla procijenjene. Inicijalno zasićeni uzorci ekspanzivnog tla podvrgnuti su sušenju. Pokusi sušenja uspješno su simulirani numeričkim modelom ne temelju procijenjenih značajki materijala.

Bentonit kao mineralna komponenta bentonitnih tepiha ima važna fizička i kemijska svojstva koja mu osiguravaju vrlo malu hidrauličku propusnost. Glavni sastojak bentonita je mineral glina naziva montmorillonit koji vrlo malu propusnost može zahvaliti sposobnosti bubrenja. Ležišta bentonita rasprostiru se posvuda po svijetu, međutim, samo mali broj njih zadovoljava uvjete kvalitete i trajnosti potrebne za upotrebu u brtvenim barijerama. Ovisno o mjestu ugradnje i namjeni, bentonitni tepisi moraju zadovoljiti određene kriterije. Sukladnost s propisanim kriterijima potvrđuje se različitim laboratorijskim postupcima. U te postupke ubrajaju se i pokusi za ispitivanje indeksnih pokazatelja (indeks slobodnog bubrenja, indeks gubitka fluida i kapacitet upijanja vode). U ovom radu prikazana su zapažanja o utjecaju temperature i relativne vlažnosti prostora u kojemu se provodi ispitivanje na dobivene vrijednosti kapaciteta upijanja, jednog od kriterija koji bentonit mora zadovoljiti prilikom kontrole kvalitete i trajnosti mineralne komponente bentonitnih tepiha.

U radu su prikazana iskustva u kreiranju i implementaciji Bolonjskih programa na studijima rudarstva, naftnog rudarstva i geologije, kao i akreditaciji laboratorija i visokoškolskih institucija u RH.

U dokumentu je navedeno područje djalovanja i ustroj RGN fakulteta, prikazana je SWOT analiza, definirane su misija i vizija fakulteta te opći i posebni ciljevi razvoja fakulteta u nastavi, znanstveno-istraživačkom i razvojno-stručnom radu te sustavu osiguranja kvalitete i upravljanja resursima.

This paper presents a brief summary of the earth reinforcement technology, its applicability for various types of transportation projects and foundation soil conditions. Stressed is that use of this technology in addressing soil stabilization needs of transportation project can result in effective design solutions and achieve cost savings on large scale projects. The paper reports case study that illustrates the concept of design and construction issues related to this type of construction. Presented are design and practice of reinforced earth walls in karst region along the highway Split-Ploče. In the paper it is discussed that reinforced earth structures also serve for protection of environment, because they may play roll as storage for a great amount of crushed stone that is produced by cutting way through rocks. On the other hand, crushed stone is very suitable for this type of structures because of its high frictional resistance characteristics. In the paper, shortly is presented a stability calculation for the reinforced earth wall Strikići, the highest from until now built reinforced earth wall along the Split – Ploče highway. Special consideration is given to performance of reinforced earth walls during earthquakes. Finally, authors conclude that reinforced earth technology is a relatively straightforward and cost-effective construction process. Coupled with historically good performance under both static and seismic conditions makes earth reinforcement a valuable method in soil stabilization.

The use of bentonite, either as a component of BES (bentonite enhanced soil) or mineral component of GBR-Cs (clay geosynthetic barrier) has become a standard practice for the construction of landfills in geotechnical and hydrotechnical structures. They are used as a key component of hydraulic barrier system. Depending upon the location and function, GBR-Cs have to fulfill certain conditions. The subject of this study is Na-activated bentonite currently used for the production of additives for foundries and pet litter. The goal was to evaluate the quality and performances of Na-activated bentonite required for environmental applications and determine the possibility of potential use for liner applications. Index testing was performed by the following methods: swell index, fluid loss and water absorption capacity of bentonite. Additionally, permeability testing has been done. On the basis of the testing performed it can be concluded that the tested type of Na-activated bentonite could be used for the manufacturing of GBR-Cs.

Geosintetičke glinene barijere (GBR-Cs) intenzivno se koriste kao brtveni elementi u geotehničkim i hidrotehničkim objektima te u inženjerstvu zaštite okoliša. Ovisno o mjestu ugradnje i namjeni, geosintetičke glinene barijere moraju zadovoljiti različite kriterije. Mineralna komponenta geosintetičke glinene barijere predstavlja element koji obavlja funkciju brtvljenja, pa je i ispitivanje kvalitete gline ključno u proizvodnji geosintetičkih glinenih barijera. U ovom radu prikazana su ispitivanja kvalitete gline na tri uzorka radi određivanja mogućnosti njihove uporabe u svrhu proizvodnje geosintetičkih glinenih barijera. Dva su uzorka dobivena iz ležišta Sokolac (Šipovo, BiH) i Vranjska Banja (Srbija), a jedan je uzorak aktivirani natrijski bentonit (Bentoplast) dobiven u tvornici umjetnih gnojiva Petrokemija d.d., Kutina. Trenutno se miješanjem prirodne komponente i njezinom aktivacijom natrijem dobiva proizvod koji se koristi za proizvodnju dodataka u ljevarstvu i stelja za kućne ljubimce. U ovom radu prikazani su rezultati provedenih ispitivanja koja uključuju određivanje kemijskih i mineraloških svojstava, indeksnih pokazatelja (indeks bubrenja, gubitak fluida i sposobnost upijanja vode) te hidrauličke propusnosti, kako bi se utvrdila mogućnost potencijalne uporabe aktiviranog bentonita za izgradnju brtvenih barijera.

Znanstveni program s ovim naslovom prihvaćen je i podržan od strane Ministarstva znanosti, obrazovanja i športa, a obuhvaća sedam znanstvenih projekata čiji su voditelji koautori članka. Namjera ovog članka je da se upozna relevantnu javnost o radu na projektima, ciljevima i očekivanjima istraživanja i njihovom značaju za praksu u Hrvatskoj. U članku se navode pretpostavke istraživanja, metode istraživanja, ciljevi i očekivani rezultati istraživanja i međusobna povezanost projekata.

Rudarsko-geološko-naftni fakultet Sveučilišta u Zagrebu je mjesto gdje se obrazuju stručnjaci za gospodarenje mineralnim i energetskim sirovinama. Raznovrsnošću predmeta koji zadiru u mnoge grane tehnike i prirodoslovlja, RGN fakultet obrazuje polidisciplinarne stručnjake široke i kompleksne naobrazbe za obavljanje djelatnosti u različitim područjima proizvodnje i gospodarstva.

Geosynthetic clay liners (GCLs) are mostly used in geoenvironmental engineering. Top and bottom liners are key elements in every landfill. They are usually made as compacted clay liners but some alternative solutions such as GCLs could be used as well, mostly in combination with some other materials. According to the experience in other countries, GCLs have been used in Croatian landfills for several years. Depending upon location and function, GCLs have to fulfil certain conditions. In order to prove the compliance of GCLs properties with the requirements of legal acts and design solutions, laboratory testing is used regularly. The results of some laboratory tests conducted on the specimens of GCLs will be presented in the paper, namely: oedometer tests, direct shear tests and compatibility tests.

Coefficient of permeability is the most important design parameter of clays and geosynthetic clay liners (GCLs) for landfill liner applications. It can be determined using conventional (constant- or variable-head method) or modern test methods like flow-pump testing (Veinovic et al., 2003). By applying flow-pump method, permeability measurements can be obtained much more precisely and rapidly, which is particularly important for low permeable and soft materials. In our study, samples of one type of reinforced GCL were tested for the determination of permeability by two methods: constant-head (samples 1 and 2) and flow-pump (samples 3 and 4). The obtained values of permeability were quite similar in both cases. The major advantage of flow-pump method was that the duration of permeability testing phase was only several hours comparing to several days in case of constant-head method (Blazevic, 2007).

During the 1880 Zagreb earthquake (M = 6.3) liquefaction occurred at several locations. In the paper the first approach of evaluation for liquefaction susceptibility of Sava sediments in vicinity of Zagreb is presented. Evaluation has been performed according to “ Eurocode 8” , “ Manual for Zonation on Seismic Geotechnical Hazards” (1999) and state-of-the-art reports on liquefaction. Absolute dating (14C) of fossilized trees samples, collected at five locations, has been performed, which represents the only experiments of this kind performed for River Sava deposits at Zagreb area related to evaluation for liquefaction susceptibility. Result of the evaluation for liquefaction susceptibility is preliminary qualitative prognostic map of lique-faction potential for Zagreb area.

Definicije i termini. Vrste i namjena bentonitnih tepiha (GCL-a) u odlagalištima otpada. Armirani i nearmirani bentonitni tepisi. Komponente bentonitnog tepiha: mineralna (bentonitna glina) i sintetička (geotekstil, geomembrana). Prednosti i nedostaci bentonitnih tepiha (GCL) u odnosu na klasični brtveni sustav načinjen od zbijene gline (CCL). Upotreba GCL-a kod odlagališta otpada: temeljni brtveni sustav, završni pokrov. Pregled normi za laboratorijsko ispitivanje fizičko- mehaničkih svojstava GCL-a (ASTM i EU norme). Indeksni pokazatelji: indeks slobodnog bubrenje, kapacitet apsorpcije, gubitak fluida. Ispitivanje propusnosti GCL-a: tekućine i plin. Ispitivanje stišljivosti i bubrivosti GCLa. Kontaktna i unutrašnja posmična čvrstoća GCL-a. Utjecaj vanjskih (okolišnih) uvjeta na dugotrajnu funkcionalnost GCL-a: sušenje-vlaženje, smrzavanje-odmrzavanje, kemijska kompatibilnost. Pitanje ekvivalentnosti GCL-a i CCL-a. Interakcija GCL-a s drugim komponentama temeljnog i pokrovnog brtvenog sustava – osvrt na projektiranje i ugradnju. Neki primjeri iz prakse.

Environmental education has been included in primary and secondary school curricula in Croatia for years, mainly through the subjects connected to the nature and human health. After signing Bologna declaration in 2001, the reform of higher education system started in accordance with the new Act on Scientific Activity and Higher Education. It presented a possibility to form new study programs within the area of higher education, orientated towards education of specialists for environmental protection. Problems related to environmental protection are of interdisciplinary character, so education of specialists for these fields relate to different scientific areas. This article analyses development of study programs for environmental geotechnics at the University of Zagreb in greater details.

Temeljni i pokrovni brtveni sustavi sastavni su elementi svakog odlagališta. Najčešće se izvode kao klasični sustavi od zbijene gline točno određenih svojstava (CCL – compacted clay liner) ili korištenjem nekog od alternativnih rješenja kao što su: bentonitni tepisi (GCL – geosynthetic clay liner), bentonitom poboljšana tla (BES – bentonite enhanced soils), te mješavine glina s polimerima. Prateći svjetske trendove, i u Hrvatskoj se već više godina primjenjuju bentonitni tepisi u odlagalištima otpada. Ovisno o mjestu ugradnje i namjeni, bentonitni tepisi moraju zadovoljiti različite kriterije. Sukladnost s propisanim kriterijima potvrđuje se različitim laboratorijskim postupcima. U ovom radu prikazani su rezultati ispitivanja posmične čvrstoće i kemijske kompatibilnosti bentonitnih tepiha, te probna ispitivanja hidrauličke propusnosti na uzorcima kaolinske gline.

Definicije i termini. Vrste i namjena. Armirani i nearmirani bentonitni tepisi. Komponente bentonitnog tepiha: mineralna (bentonitna glina) i sintetička (geotekstil, geomembrana). Upotreba GCLa u geotehničkom inženjerstvu. Upotreba GCLa u odlagalištima otpada. Pregled normi za laboratorijsko ispitivanje GCL-a. Laboratorijsko ispitivanje stišljivosti i bubrivosti, posmične čvrstoće i kompatibilnosti GCLa - opis ispitnih metoda i postupaka. Pitanje ekvivalentnosti GCL-a i CCL-a.

Na Rudarsko-geološko-naftnom fakultetu obrazuju se stručnjaci iz područja tehničkih i prirodnih znanosti. Pri definiranju studijskih programa korišteno je iskustvo vodećih europskih sveučilišta uz nužne prilagodbe zbog sustava obrazovanja i tržišta rada u Hrvatskoj. Reformom se nastojalo riješiti i tradicionalno prisutne probleme poput nedovoljne atraktivnosti studija, dugotrajnog studiranja i malog broja diplomiranih u odnosu na upisne kvote. U realizaciji novih programa nailazi se na niz problema. Dio studenata i nastavnika nije u potpunosti prihvatio novi način studiranja. Provođenje ispitivanja i ocjenjivanja rada studenata nije sustavno riješeno. Pri ostvarivanja prava po drugim propisima studenti nailaze na prepreke jer isti nisu usklađeni s promjenama u sustavu visokog školstva. Uvođenjem školarina bez osiguranja financiranja studija putem stipendija i kredita, studenti lošijeg imovinskog stanja dovedeni su u neravnopravan položaj. Praćenjem provedbe programa uočeni su i sljedeći problemi: preopterećenost studenata, preklapanje sadržaja predmeta, prestrogi uvjeti slijednosti predmeta, nedovoljna uključenost studenata u proces evaluacije programa i vrednovanja kolegija putem ECTS-a. Aktivnosti provedene s ciljem bolje provedbe procesa su: Dekanat je certificiran po normi ISO 9001:2000 kako bi se poboljšao rad stručnih službi ; financira se izobrazba nastavnika (e-učenje, pedagoški programi) ; pored sveučilišne ankete fakultet od ranije provodi vlastitu anketu a rezultati se koriste za determiniranje problema ali i nagrađivanje najboljih nastavnika ; donacijama privrednih tvrtki opremljeno je nekoliko učionica. Predviđene su i mjere poput: intenziviranje rada vijeća studija, uključivanje u evaluaciju programa interesnih skupina poput poslodavaca, Ministarstava i sl.

Na Rudarsko-geološko-naftnom fakultetu u Zagrebu načinjen je online tečaj iz kolegija Mehanika tla, koji se predaje na preddiplomskom ciklusu visokoškolskog obrazovanja. Brojne mogućnosti WebCT alata, potaknule su stvaranje cjelovitog online tečaja koji se trenutno koristi kao sredstvo za obogaćivanje konvencionalne nastave.

Faculty of Mining, Geology and Petroleum Engineering (FMGPE), University of Zagreb, Croatia is an institution of higher education that educates professionals in the area of technical sciences, mining, petroleum and geological engineering field, and in the area of natural sciences, geoscience field. According to a new curriculum recently proposed to the National council for higher education, FMGPE offers three undergraduate and four graduate programs. The study programs are designed according to the latest scientific achievements, professional and practically utilized technologies and trends in knowledge and skill development in the world, and by taking into account the rules given by Bologna declaration (3+2 tier system). The paper will describe in detail the proposed programs together with the expected outcomes, especially related to: the needs of Croatian and regional industry ; the development of new areas of education (environmental programs) ; and the improvement of certain skills like communication, interdisciplinary cooperation and computer literacy.

Geosynthetic materials such as geomembranes and geosynthetic clay liners (GCLs) are frequently used in composite clay liners for landfills. In line with ASTM recommendation the clay portion of a GCL should be tested for chemical compatibility to liquids. A series of mineral composition, swell index, fluid loss and water absorption capacity tests of bentonite were conducted. The site-specific liquid i.e. real leachate was collected from the leachate retention basin of a municipal solid waste disposal site Jakuševac near Zagreb. Besides the baseline testing performed on “ as-received” samples (series I), three other series of tests were also made. GCLs mineral component (bentonite) was immersed into the leachate during different periods of time for two series (II and III), after what index tests were performed using demineralized water as a test fluid. The last series of experiments (series IV) was conducted using the site specific liquid as a test fluid. Water absorption test indicate the decrease of absorption capacity with the increase of sample immersion time into the leachate: the longer immersion period, the smaller absorption capacity. Test results for fluid loss yield no significant difference in values obtained with “ as-received” samples in comparison with samples immersed into the site specific liquid. The results for samples immersed into the site specific liquid (series II and III) show the increase of swell index with the duration of immersion comparing to baseline testing (series I). On a contrary, the tests performed with site specific liquid as test fluid (series IV) show much lower swell index. Mineral composition has been determined by X-ray powder diffraction (XRD). XRD analyses indicate that the sample contains about 75% of clay minerals with majority of the minerals being smectite. The change of basal spacingis noticed for samples immersed into the leachate. It is also interesting to note that these changes occurred immediately after immersion because the results of series II (7days) and series III (60 days) do not show almost any difference. XRD analysis and index tests conducted on specimens immersed into the site specific leachate during different periods of time showed some influence of leachate to the bentonite behaviour. However, swell index tests conducted using the site specific leachate as a test fluid showed significant influence of leachate to the bentonite.

Bentonitni tepisi (GCL - geosynthetic clay liner) sve su češće prisutni u brtvenim sustavima na odlagalištima otpada, kako u svijetu tako i u Hrvatskoj. Dugotrajna funkcionalnost bentonitnih tepiha značajno ovisi o ponašanju mineralne komponente (bentonitna glina) u kontaktu s kemijskim tvarima prisutnim u eluatu. Sukladnost bentonitnih tepiha projektnim zahtjevima provjerava se ispitivanjem kemijske kompatibilnosti mineralne komponente i eluata (tzv. site-specific liquid). U članku su prikazani rezultati laboratorijskog ispitivanja mineralnog sastava, te indeksnih pokazatelja bentonitne gline: indeks bubrenja, indeks gubitka fluida te sposobnost absorpcije. Ispitivanja su provedena prema važećim normama i uz korištenje bentonitnog tepiha i eluata s odlagališta « Jakuševec» . Rezultati pokazuju blagi utjecaj eluata na svojstva bentonitne gline ukoliko se eluat koristi samo za pripremu uzoraka, a pokusi provode demineraliziranom vodom. Međutim, indeks bubrenja značajno se promijenio kada je kao ispitni fluid korišten odlagališni eluat.