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Determination of the relevant soil stratigraphy is of the paramount importance for any geotechnical analysis. The cone penetration test (CPT) is the cost-effective, rapid, continuous, and reliable testing method for assessing soil layering and estimating in-situ mechanical properties of soil, and as such is especially useful for subsoil investigations along linear infrastructure networks, such as roads, highways, or railways. The design soil profile can be effectively determined using the CPT-based soil behaviour type (SBT) classification system. However, the soil profile consists of layers of various thickness and some layers can be only a few centimetres thick. Because the cone needs to penetrate to a certain depth to develop the cone resistance and to identify the presence of another layer, thin layers of soil cannot be properly detected. The soil layering algorithm, presented in this paper, merges these thin layers into the adjacent layers and thus overcomes the unreliable determination of the thin layers. The implementation of the proposed algorithm is demonstrated using a CPT carried out on the embankment test-site in north Croatia.

As natural or artificial earthen structures that provides flood protection adjacent to rivers or coastal areas, levees should be verified for several relevant design situations. For this verification, Eurocode 7 adopts semi-probabilistic approach, which utilizes statistical methods to select characteristic values of geotechnical parameters, thus neglecting spatial correlation between the same parameter at different sampling points, and cross-correlation between different parameters at the same sampling point. The degree of uncertainty involved in calculation of levee response to seismic loads is especially high and implementation of probabilistic approach for evaluation of seismic resilience of levees will yield more reliable insight into the behaviour of levees both during low and high waters. This paper contributes to the efforts of levee seismic vulnerability evaluations, through development of fragility curves as functions that describe the conditional probability of levee stability failure over the full range of seismic and water loads to which the levee might be exposed.

Buildings that have been subjected to seismic impacts must initially be assessed. The assessment is done in order to determine the degree of damage to buildings. Defining the method of intervention depends on the assessment. Generally, the assessment can be done using Eurocode norms, ACI, SIA, etc. The assesment of buildings determines the ability of buildings to be durable, even against a new possible earthquake of the same magnitutde or even stronger. The assessment should result in clear decision which buildings are close to collapse, and which are suitable for an intervention. Assessments should also take into account the importance of buildings such as historical, cultural, public, etc.

This paper proposes a remediation solution for the sinkholes appeared as a consequence of a devastating earthquake of 6.2 magnitude which hit Croatia in December 2020. At the time of writing this paper, more than 90 sinkholes in villages Mečenčani and Borojevići opened, all triggered by the main impact as well by the series of aftershocks, leaving both authorities and public, as well the professional – scientific community, in surprise. The sinkholes are identified as the cover collapse sinkholes, a most dangerous type of a sinkhole which collapses without any prior ground surface deformation. Owing to the fact that the conditions for the formation of these phenomena are in geological setting of this sinkhole prone area, characterized by the proluvial deposits underlain by the soluble karstic rock mass, the necessity of appropriate investigation works and remediation techniques is highlighted. Since the sinkholes are presumably well-integrated into the karstic conduit system of the aquifer, part of which is a water supply source Pasha's spring, the remediation techniques should rely on the permeable grained fills with minimized utilization of cement or chemical – based materials.

In the morning of 22 March 2020 at 5:24 (UTC) a damaging earthquake struck Zagreb, the capital of Croatia. This shallow local magnitude 5, 5 earthquake was the strongest instrumentally recorded earthquake in the NW part of Croatia since 1908 when the first seismological station was installed in Zagreb. The strongest aftershock of local magnitude 4, 9 happened at 6:01 (UTC) on the same day. Both events were recorded by two strong motion stations in the City of Zagreb, located close to the epicentres (10 km).

2020 Zagreb earthquake and 2020 Petrinja earthquake raised the topic of urban renewal process and possible renewal models for damaged buildings. The paper presents the author's research from the first semester of the Postgraduate doctoral scientific study programme Architecture and Urban Planning at the Faculty of Architecture in Zagreb. The main goal of urban renewal is the process of modernization that has to be in accordance with preservation of cultural heritage and city's identity. Renewal models for private buildings under conservation protection are researched, as well as their impact on the process of integral urban renewal of the city of Zagreb. Renovation models are researched interdisciplinary from the aspect of urban planning, architectural practice and theory, civil engineering, art history and sociology. The advantages and disadvantages of each renewal model are analysed, as well as the possibilities of their implementation. Each renewal model has different impact on visual identity of the city and different level of possibility for implementation of deep renewal which includes adaptive reuse, upgrade of earthquake resistance and fire protection, energy retrofit, improving accessibility for the disabled, parking area extension, interior renovation, yard renovation, etc. Four possible renewal models have been identified for apartment buildings within the protected area of the Zagreb Lower Town: Model A - renovation of existing structures, Model B - demolition of existing buildings and reconstruction with preserving only the original appearance of the street facade, Model C - demolition of existing buildings and construction of completely new buildings, Model D - demolition of existing buildings and gaining benefits from spatial voids. The research also deals with the topic of preserving the city's identity and paradoxical relations arising from conservation rules, as well as with the impact of urban rules and legislation on the urban renewal implementation. Reconstruction of Warsaw after the WWII and interventions in the attics in Vienna are shown as examples.

U radu se daje prikaz aktivnosti koje se provode u okviru znanstveno-istraživačkog projekta oVERFLOw, financiranog kroz mehanizam civilne zaštite EU. Zajedno sa upraviteljima infrastrukturom i društvima civilne zaštite, konzorcij partnera iz Hrvatske, Slovenije i Nizozemske, implementira novostečena znanja i iskustva na dva pilot područja u Nizozemskoj i u Hrvatskoj. Sveobuhvatan pristup ocjeni ranjivosti nasipa i obaloutvrda, kao ključnih karika u sustavu zaštite od štetnog djelovanja voda, obuhvaća detaljne i inovativne metode ocjene postojećeg stanja koje služe kao ulaz za probabilističke analize evaluacije njihove ranjivosti na niz mehanizama prekoračenja graničnih stanja. Osim toga, projekt analizira i osjetljivost mostova kao ključnih infrastrukturnih elemenata evakuacijskih puteva tijekom poplavnih događaja.

On 29 December 2020 destructive M6.2 earthquake hit well known Petrinja epicentral area, and caused strong damage on many buildings in Petrinja, Sisak, and Glina, as well as on solid modern linear infrastructure (roads, bridges, artificial river embankments, pipelines etc.). The seismic hazard is not depending only on the estimated coseismic ground acceleration that should be used for EUROCODE 8 constructional seismic design, but is also strongly dependent on local soil effects and on the secondary effects of a strong earthquake (landslides, liquefaction, suffosion, etc.). Besides, movement of the crustal blocks along the fault lines that cross the solid objects, in case of surface coseismic rupture such was the Petrinja event, should be evaluated. Local site amplification effects are the results of several physical processes (multiple reflections and diffractions, focusing, resonance, wave trapping) in the overlying superifical deposits and soil, resulting in variable damage distribution that were observed in different local geological units affected by an earthquake. Also, the variable surface topography and various mechanical properties of the terrain such as water table, slopes, presence of heterogeneities, structural discontinuities and cavities, certainly can contribute to the observed damage and increase geological hazard in epicentral area. How many unknown active faults we can identified in Croatia? What could be surface manifestation of a strong earthquake that will occur on a shallow thrust (reverse) fault? Is there any major normal active fault that can surprise seismotectonic experts and civil engineers? The authors published first scientific paper after the Zagreb 22 March 2020 event and are currently working on active tectonics in Kvarner region and Hrvatsko Zagorje. Besides, a new Croatian Science Foundation (HRZZ) project has just been started with special attention on soil dynamic properties and its influence on the seismic hazard of the older cultural buildings in Trakošćan, Šibenik and Dubrovnik.

In nuclear power plants, diesel generator sets (gensets) are used for emergency situations, and regularly such gensets are consisted of a diesel engine, generator, and corresponding base frames mounted on elastic supports (usually spring-damper elements). Such dynamic systems should be properly designed to withstand combinations of different loadings like those originating from: earthquake, short circuit, synchronization failure as well as unbalanced diesel engine internal forces, and the analysis should be done with respect to genset static deflection due to its weight. This work outlines a procedure to evaluate the structural integrity of diesel generator base frame supports subjected to combinations of static, seismic, short circuit and synchronization fault loadings, for the needs of its installation in a Nuclear Power Plant in Ruppur, Bangladesh.

U radu se daje prikaz projektnog rješenja rekonstrukcije uspornih nasipa za obranu od poplava uz rijeku Trnavu. Rekonstrukcija se izvodi zasijecanjem tijela postojećeg nasipa te izvedbom novog nasipa većih dimenzija, sve kako bi se zadovoljili kriteriji osiguranja mehaničke otpornosti i stabilnosti pri mjerodavnim vodostajima. Međutim, uzimajući u obzir prostorna ograničenja, gdje su nagibi pokosa nasipa uvjetovani visinom nasipa i blizinom vodotoka Trnave te činjenicu da su nasipi projektirani prema relevantnim standardima Eurokoda 7, tehničko rješenje rekonstrukcije je obuhvatilo i ugradnju jednoosnih polimernih geomreža, sve u cilju povećanja stabilnosti za relevantne projektne situacije