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The adhesive strength of non-structural lime-based grouts used to stabilise sensitive, detached, decorative plasters is an important mechanical property. However, it is difficult to determine it due to the lack of suitable standard test methods. The existing standard procedures are mainly aimed at testing the properties of hydraulic binders and are not suitable for injection grouts or mortar specimens based on a lime binder. In the present study, the focus is on a comparison of the pull-off results between the standardised method (EN 1015-12) performed on pre-drilled specimens on sandwich panels (PMS) and the modified method using sandwich discs (DSS). It was found that the modified method with sandwich discs (DSS) achieved an up to 58 % higher adhesive strength than the standard method with sandwich panels. In the sandwich-panel specimens, fracture occurred in the grout since pre-drilling reduced the cohesive strength of the grout. For the sandwich discs (DSS), fractures occurred predominantly at the interface between the mortar and the grout.

This paper investigates the origin of increased strength and water resistance of air lime mortar prepared by Triassic dolomite aggregate when exposed to humid or wet environments. The mortar specimens were exposed to various ageing conditions and analysed using petrographic and scanning electron microscopy equipped with X-ray microanalysis. Parallel to these analyses, X-ray powder diffraction and strength tests were performed on the specimens. It was revealed that reactions associated with the dedolomitisation process of the dolomite grains in the lime binder (hereafter alkali-carbonate reactions or ACRs) are the source of the improved strength and water resistance. An increasingly alkaline environment accelerated the ACRs substantially. Two parallel processes during the ACRs (dedolomitisation and CaCO3 dissolution/reprecipitation) were described in detail. Ageing temperature decisively influenced the kinetics of the dedolomitisation and dictated the path of the CaCO3 dissolution/reprecipitation process. After two years of ageing in a water-saturated environment at 60 °C, air lime mortar retained a great deal of its initial mechanical strength, and at 20 °C its strength was considerably increased. This somewhat unexpected observation was explained as being a result of microstructural changes and/or phase transitions.

Dry hydrated lime is an air binder often used in architectural injection grouts. This study compared the influences of three commercially available dry hydrated limes on the injection grouts’ workability and mechanical properties. The main differences between the limes were in their chemical and mineralogical composition and Blaine specific surface area. The grouts were composed of dry hydrated lime, finely ground limestone filler, water, and super plasticiser. Subsequent results obtained revealed that the Blaine specific surface area is not directly related to the fresh grout properties. Grain size distribution and shape of lime particles and their aggregates in the water suspension are key parameters influencing the following fresh grout properties: fluidity, injectability, the mixture’s stability, and water retention capacity. However, the lime injection grouts’ mechanical strengths were higher in relation to an increase in the content of portlandite and the Blaine specific surface area of the dry hydrate.

Blended cements might change the chemistry of the pore solution and subsequently affect the corrosion of steel in concrete. Pore solutions were extracted, analyzed and compared from mortars made of CEM I, CEM II, CEM III and CEM IV cements. Three combinations of carbonation and chloride states were studied, i.e., non-carbonated without chlorides, non-carbonated with chlorides and carbonated with chlorides. Different electrochemical and spectroscopic techniques were used to study the electrochemical properties, the type and the extent of the corrosion products, as well as the type and the extent of the corrosion damage. It was confirmed that the most corrosive environments were pore solutions extracted from the carbonated mortars with chlorides. In this environment the highest corrosion rate was observed for the CEM III pore solution, and the lowest for the CEM I. The extent and the type of corrosion products and the corrosion damage varied according to the environment.

Microstructure development of concrete, mortar, and paste scale of cement-based material (CBM) during the early hydration stage has a significant impact on CBM’s physical, mechanical, and durability characteristics at the high maturity state. The research was carried out using compositions with increased autogenous shrinkage and extended early age period, proposed within the RRT+ programme of the COST Action TU1404. The electrical conductivity method, used to follow the solidification process of CBM, is capable of determining the initial and final setting time, and the end of the solidification process acceleration stage for the paste and mortar scale. Simultaneous ultrasonic P- and S-wave transmission measurements revealed that the ratio of velocities VP/VS is highly dependent on the presence of aggregates—it is considerably higher for the paste scale compared to the mortar and concrete scale. The deviation from the otherwise roughly constant ratio VP/VS for each scale may indicate cracks in the material. The non-linear correlation between the dynamic and static elastic moduli valid over the three scales was confirmed. Additionally, it was found that the static E-modulus correlates very well with the square of the VS and that the VS is highly correlated to the cube compressive strength—but a separate trendline exists for each CBM scale.

Injection-grout density is an important parameter when its additional weight leads to consolidated decorative plasters becoming damaged. This is especially evident in larger detached areas. In this study, thin-walled soda&ndash, lime&ndash, borosilicate glass microspheres were used as a density-reducing constituent in hydrated lime grout mixtures. The normal density grout composition&mdash, one volume part hydrated lime and three volume parts inert limestone filler with 0.5% of the polycarboxylate ether-based superplasticiser&mdash, was modified with partial substitution of the limestone filler with lightweight glass microspheres. The following volumetric proportions between limestone filler and glass microspheres were used: 100%:0%, 67%:33%, 50%:50%, 33%:67%, and 0%:100%. With the increase of the glass microspheres&rsquo, volume, the density of the grout is gradually reduced. Furthermore, there is a decrease in the stability and injectability of fresh grout. In its hardened state, the grout&rsquo, s strength again reduces gradually, but there is no significant change in the grout&rsquo, s water absorption and water-vapour resistance. The resistance of the grout to freezing&ndash, thawing and heating&ndash, cooling cycles using distilled water or salt solution is highly improved when the microspheres are present.

This paper investigates the properties of injection grouts with different amounts of natural hydraulic lime (NHL) replacement by metakaolin MK1 or MK2. The focus is dedicated to the fresh properties of the NHL-based grouts, as well as to a parallel study of the evolution of compressive strength and phase composition of hardened grouts, through tests at 28, 56, 90 and 900 days. Additionally, at 90 days, the influence of the MK1 and MK2 incorporation on the porosity characteristics of hardened grouts was determined. Tensile bond strength, being one of the key hardened properties of the injection grouts, was for the time being determined only at an early age of 28 days. The results showed that by adding metakaolin at constant fluidity, the water demand of the fresh mixture increases with the increase of the metakaolin content. At the same time the water retention capacity of the grout is enhanced. In a hardened state the addition of metakaolin increases early age and long term compressive strength of the grout. Also, its bond strength can be considerably increased, by applying MK1. Mixtures with metakaolin resulted in the formation of hydration products such as ettringite, hemicarboaluminate and monocarboaluminate, whereas stellerite was present only in the case of higher proportions of metakaolin with a higher BET surface area and Al2O3 content.

Supplementary cementitious materials are known to refine the pore structure of concrete and accelerate the carbonation progress. The combination of the two processes can have both beneficial and disadvantageous effects on corrosion, especially when chlorides are also involved. In this study the corrosion properties of multiple blended cements were evaluated in carbonated and non‑carbonated states, with chlorides introduced through cyclic ponding. The examination involved monitoring the propagation phase, determining the microstructural properties of cements, and assessing the final corrosion damage. The results showed that the steel in the blended cements initially had a relatively high corrosion activity, which later decreased compared to the OPC. This stabilisation was presumably due to the beneficial changes to the pore structure. Carbonation had a significant impact on the corrosion, with carbonated mortars revealing shallower damage over a larger surface area. This effect was more pronounced for blended cements that exhibited greater susceptibility to carbonation.

In the described studies with the aim of optimizing hydrated lime grout composition, the first measure was to reduce the water content of the grout using a highly efficient polycarboxylate ether-based superplasticizer, whereas the second measure was to increase the content of the inert limestone filler with an adequate grain size distribution. In this way, an attempt was made to achieve the best possible volume stability and strength properties of the hydrated lime grout, while continuing to fulfill the other necessary requirements regarding non-structural grouting works which are reported in the literature.The results of the tests showed that a non-structural grout consisting of 1 volume part of hydrated lime CL 90-S and 3 volume parts of inert limestone filler, with 0.5% of the polycarboxylate ether based superplasticizer, fulfilled most of the established requirements, so that it is thus potentially suitable for re-attachment interventions on architectural surfaces.

Round Robin Testing (RRT) is a well-known method for assessing the reproducibility of a test or verification of a new test procedure of almost any kind. In the EU funded network COST Action TU1404 ‘‘Towards the next generation of standards for service life of cement-based materials and structures”, an Extended Round Robin Testing program (RRT+ ) was planned as a fundamental tool to obtain input data for a range of concrete properties and validate non-standardised testing techniques. In this paper, detailed information on the planning, conduction and analysis of Phase 1 of the RRT+ is presented. The aim of Phase 1 was to define and confirm the best practice for creating a comparable reference concrete mix for RRT programmes. With a total of 45 laboratories from Europe, Japan and Canada, RRT+ was one of the most extensive round robin testing programmes targeting cement-based materials., The authors also acknowledge the financial support of EDF, France; CEVA Logistics, Austria and Germany; OeBB Infra, Austria; Staten Vegvesen, Norway and Schleibinger Gerate, Germany. The support of the research network COST TU1404 (COST Association) is also gratefully acknowledged.

The subject of this paper is the extent to which, during wetting–drying cycles, chloride ions penetrate into fly ash modified concrete. Detailed chloride profiles were recorded which show how the total and water-soluble chloride contents vary with the depth of penetration of these ions into the concrete. In order to study the effect of exposure time, fly ash content, and fly ash composition on such penetration, two different types of fly ash were used as a partial replacement of Portland cement, their proportions amounting to 0%, 20% and 50% by weight of the binder. The results of the investigation showed that the chloride penetration depths were smaller in the case of the fly ash modified concretes than in the case of the unmodified concrete (i.e. concrete which did not contain fly ash), so that thinner layers of concrete cover could in this case be used to protect the steel reinforcement from the effects of corrosion. This indicates the potential beneficial effect of the use of fly ash on the service life of reinforced concrete structures. It is not just the porosity of the fly ash which plays a key role in the case of chloride penetration into concrete, but also the composition of the fly ash, and especially its calcium content.

Based on the results of the infrared thermography of 51 artificially created defects – voids and delaminations – in concrete, it was shown that it is possible to detect defects at depths that are equal or less than the defect size D using the thermal contrast method. By applying the phase contrast method, an increase of 50% in the maximum depth for a given defect size D was achieved. Delaminations containing thin air gaps were detected with the same success as much larger voids of the same cross section.

The research presented in this paper focuses on influence of freeze–thaw cycles accompanied by simultaneous moistening on mechanical properties of historical brick masonry. In order to evaluate the rate of reduction in mechanical properties of the masonry due to freezing and thawing, a series of brick wallets built of solid brick and lime mortar or lime-slag mortar representing an actual building envelope was subjected to testing. Besides testing the wallets and triplet specimens as a mortar–brick composite, mortar prisms and brick units were also tested separately. Wallets built with either of analysed types of lime-based mortar were able to withstand 50 freeze–thaw cycles without any effect on their mechanical properties. After 150 freeze–thaw cycles, the damage of brick surface and mortar joints increased, but had no significant effect on the compressive strength of the wallets. However, in case of wallets built with lime-slag mortar, freeze–thaw damage reflected in the reduction of modulus of elasticity. The results indicate that both tested mortar types have the potential in reconstruction and repair works carried out on historical masonry in areas exposed to freezing and thawing.

The paper summarizes the results of laboratory tests that were performed on samples of extruded polystyrene foam (XPS). The aim of the investigation was to determine the mechanical characteristics which are essential for the seismic analysis of modern low-energy building structures, where XPS boards are used as a thermal insulation layer beneath the building's foundations. As well as this, the shear behaviour of differently composed thermal insulation (TI) foundation sets was investigated, and their friction capacity estimated. The results showed that, in general, XPS material with higher compressive strength also possesses higher shear strength. Sliding between individual components of TI foundation set was revealed to be a likely failure mechanism in the case of building structures that are founded on a TI layer when subjected to strong earthquake loadings.

Some carbonate aggregates used in concrete are unstable in a high alkaline solution, which is present also in pore solution of cement binder. This paper investigates the process of dedolomitization of carbonate aggregate rocks and mortar bars. Selected aggregates, limestone and dolostone are of high purity without reactive silica involvement confirmed by the XRD and the XRF. For the process of dedolomitization the effect of various temperatures, solutions and time was examined. In this investigation, measurements of expansion, optical and scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction were used. Te results indicate that the process of dedolomitization occurred not only in the NaOH solution but also in the water on the mortar bar with virgin dolostone aggregate. Elevated temperature, 60 °C, increased the rate of reaction. Furthermore, the rate of reaction significantly correlates with time, which has also been confirmed through the Rietveld analysis.

U radu se prikazuje usporedba reoloških parametara 26 različitih svježih betona mjerenih pomoću dva koaksijalna cilindrična reometra ConTec Viscometer 5 i ICAR Rheometer. Provedeno je i mjerenje konzistencije slijeganjem i konzistencije rasprostiranjem. Statističke analize dobivenih rezultata pokazuju dobru korelaciju između dva reometra za granicu tečenja i plastičnu viskoznost. Provedenim istraživanjem ustanovljena je jaka korelacija između granice tečenja i obradivosti te slaba korelacija između obradivosti i plastične viskoznosti., The comparison of rheological parameters for 26 different types of fresh concrete, measured with two co-axial cylinder rheometers ConTec Viscometer 5 and ICAR Rheometer, is presented in the paper. The consistency by slump test and flow table test was also measured. Statistical analyses of results show good correlation between the two rheometers for the yield stress and plastic viscosity. During this study, a strong correlation was established between the yield stress and workability, while the correlation is weak between the workability and plastic viscosity.

The injection of grout into multi-leaf stone masonry walls with a sufficient amount of voids can be an effective technique for the seismic strengthening of such walls. In order to evaluate the effectiveness of different types of commercial grouts that fulfilled the adopted criteria, the stone masonry walls of an actual building were strengthened by means of grout injection, using cement and combined cement–lime grouts. The quality and effectiveness of grout injection technique was assessed by non-destructive tests (sonic and radar tests), minor destructive tests (surface and in-depth probing and coring, and the double flat jack test), and destructive test (shear-compressive test), all in situ. Preliminary laboratory tests were also performed on mortar and stone specimens, on the injection grouts, and on cylinders representing the inner core of the strengthened walls. Finally, the seismic resistance of the building was evaluated in non-strengthened and strengthened variants (i.e. after grout injection of the walls with cement or lime–cement grout) by means of non-linear static analysis, using the pushover method. Obtained results show that shear characteristics of the walls (tensile strength and stiffness) depend significantly on the type and properties of the injected grout, i.e. on the grout’s ability to achieve a solid bond between the stones and the leaves including the properties (strength and stiffness) of the grout itself. In the case of the type of masonry under consideration, an adequate level of seismic resistance can be achieved also by using combined cement–lime grouts, although cement grout can provide higher seismic resistance.

Knowledge of the structural behaviour of existing masonry requires a multi-level approach, with the proper application of diagnostic and assessment methodologies. The structural performance of masonry wall structures can be understood provided that the history of their construction, their geometry, the characteristics of their masonry texture, and the characteristics of the masonry as a composite material are known. In order to obtain all these data, an effective on-site testing program, which can involve the application of different test methodologies as a combination of destructive tests (DT), minor destructive tests (MDT) and non-destructive tests (NDT), needs to be performed. Furthermore, the effectiveness of applied methodologies for the assessment of historical masonry structures strongly depends on the type of investigated structure, as well as on the appropriate numerical model for the analysis. However, the unclear aspects of any testing programme remain the same – how efficient is a particular testing technique, and how can it be assessed? Following the results of recently carried out EU and national research projects, a comprehensive set of data regarding the effectiveness of different testing methods, depending on the type of problem, have been collected and analyzed. Within this framework, several masonry heritage structures from Slovenia, which differ both from the historical and structural point of view (Pisece Castle, the Carthusian Monastery at Žice, and a typical stone-masonry house from the Soca Valley region), have been investigated by means of different techniques, and numerically analyzed. For this purpose, two different models were used: a push-over model based, on the structural element method, and FEM analysis. It was concluded that the effectiveness of any particular diagnostic technique for the investigation of masonry structures, and for the planning of their restoration, depends on numerous factors. An attempt to determine which of the techniques could be appropriate, depending on the problem, was made. No single test is self-sufficient for the solving of a particular problem, so a combination of different NDT, MDT and DT should be performed. Summarizing all the results, it can be said that, in the process of assessing the state of a structure, even a simple investigation technique is better than none. The effort will always be repaid - if not already in the planning stage of the restoration and retrofitting actions, then certainly in the execution stage of the revitalization works, on site.

Estimating the performance of structural elements requires the assessment of the response of those elements in terms of their response values (i.e. strengths, stresses, drifts, cracks, etc.) against loads and external forces of various kinds. For the seismic performance of masonry structures, until recently this approach was addressed in rather general terms with designers more interested in the survival of the structure in a maximum expected earthquake, with an acceptably low probability of occurrence. This traditional approach to seismic design is being replaced by performance-based design with the required performance depending on the level of the design seismic forces. This paper provides an overview of some of the methods for the evaluation of the in-plane resistance of masonry walls, which are already incorporated in national codes. Some results of recent experimental investigations of the shear capacity of in-plane loaded masonry walls subjected to cyclic loading are also presented with the aim of studying the potential for the application of these new concepts of assessment of seismic performance. The performance of unreinforced masonry walls in relation to the different design performance objectives and performance levels is then discussed. Copyright © 2008 John Wiley & Sons, Ltd.

In this paper, the applicability of the ultrasonic wave transmission method to estimate the initial setting time of an arbitrary cement paste is discussed. Ultrasonic pulse velocity measurements were fully automated and measured continuously. The Vicar Needle Test was used in order to determine the initial setting time of cement pastes. Different cement pastes were prepared in order to check the influence of the water/cement ratio, type of cement, curing temperature, cement fineness, and some clinker compositions, on the relationship between the initial setting time and ultrasonic pulse velocity. It was found that the initial setting time of an arbitrary cement paste can be estimated very accurately by the time the first inflection point appears on the ultrasonic pulse velocity curve. Moreover, it can be estimated quite accurately by the time the ultrasonic pulse velocity reaches a fixed value, close to the value of the ultrasonic pulse velocity in water.

The microscopic determination of air void characteristics in hardened concrete, defined in EN 480-11 as the linear-traverse method, is an extremely time-consuming and tedious task. Over past decades, several researchers have proposed relatively expensive mechanical automated systems which could replace the human operator in this procedure. Recently, the appearance of new high-resolution flatbed scanners has made it possible for the procedure to be automated in a fully-computerized and thus cost-effective way. The results of our work indicate the high sensitivity of such image analysis automated systems firstly to the quality of sample surface preparation, secondly to the selection of the air void threshold value, and finally to the selection of the probe system. However, it can be concluded that in case of careful validation and the use of the approach which is proposed in the paper, such automated systems can give very good estimate of the air void system parameters, defined in EN 480-11. The amount of time saved by using such a procedure is immense, and there is also the possibility of using alternative stereological methods to assess other, perhaps also important, characteristics of air void system in hardened concrete.

Este artigo apresenta experiencias obtidas no decorrer da aplicacao e teste de diferentes fachadas em cal pura que poderao vir a ser usadas com sucesso no restauro de edificios historicos na Eslovenia. Cada fachada de cal e composta por uma camada de revestimento (argamassa grosseira), uma camada de acabamento (argamassa fina) e uma camada protectora de agua de cal. Para a concepcao das argamassas foram escolhidos diferentes tipos de cal, de producao industrial e tradicional, com base em estudos preliminares dos autores e em experiencias de uma pequena empresa (SE) envolvida no estudo. As camadas que compoem as fachadas foram aplicadas na parede norte - a mais problematica - de uma capela historica em alvenaria de pedra ordinaria. Esta capela pertence ao castelo de Crnelo, construido no final do seculo XVII em Turnse, uma vila nao muito distante de Liubliana, capital da Eslovenia. As fachadas foram efectuadas por trabalhadores habilitados da SE, com um intervalo de cerca de um ano entre a aplicacao das camadas de revestimento e de acabamento, e com a camada protectora de agua de cal pigmentada aplicada um a tres dias apos a execucao das camadas de acabamento. Previamente a aplicacao das camadas de acabamento, foram conduzidas inspeccao visual, medicoes de absorcao de agua e determinacao da profundidade de carbonatacao nas camadas de revestimento. Identicos testes in-situ foram subsequentemente conduzidos nas camadas de acabamento. Ate agora, paralelamente aos testes in-situ, foram efectuados em laboratorio testes de resistencia a compressao e de absorcao de agua sobre prismas preparados com as argamassas grosseiras.

Nonpozzolanic fillers are frequently used to optimise the particle packing and flow behaviour of cementitious paste in self-compacting concrete (SCC) mixes. This paper deals with the influence of finely ground limestone and crushed limestone dust on the properties of SCC mixes in the fresh and hardened state. Mixes were prepared using poorly graded crushed limestone aggregate. To compensate the lack of fine material in the crushed sand, a viscosity agent (VA) was added to the mixtures. The results obtained indicate that finer and better-graded limestone dust significantly increases the deformability of the paste. When a high volume of this filler was added to the SCC mix, the required self-compacting properties were achieved at a lower water/(cement+filler) ratio, and it also appeared that the addition of filler improves the 28-day compressive strength of concrete mixes due to the filler effect and improved fine-particle packing.

Injektiranje je jedan od najdjelotvornijih, a često i najprikladnijih postupaka za ojačanje zidova starih zidanih građevina. Da bi se ocijenio utjecaj raznih vrsta injekcijskih smjesa na mehanička svojstva zidanih građevina, obavljeno je ispitivanje in situ postojeće zidane građevine. Dobiveni rezultati korišteni su za ocjenu seizmičke otpornosti građevine pomoću metode postupnog guranja, uz primjenu pristupa katnog mehanizma i mehanizma globalnog odziva. Prihvatljivije vrste injekcijskih smjesa usporedive su s cementnim injekcijskim smjesama. Dobiveno je da se pristupom globalnog odziva postižu realniji rezultati čak i kod niskih zidanih građevina., Grout injection is one of the most effective and often most appropriate techniques for strengthening of old stone masonry walls. In order to assess the influence of different types of injection grouts on the mechanical properties of masonry, an actual stone masonry building was tested in-situ using various testing methods. The results obtained were used to evaluate seismic resistance of a building using the pushover method, and considering the storey mechanism approach and the global response mechanism. More compatible types of grouts can match cement grouts. The results show that the global response approach provides more realistic results even for low-rise masonry buildings.

Injektiranje je jedan od najdjelotvornijih, a cesto i najprikladnijih postupaka za pojacanje zidova starih zidanih građevina. Da bi se ocijenio utjecaj raznih vrsta injekcijskih smjesa na mehanicka svojstva zidanih građevina, obavljeno je ispitivanje in situ postojece zidane građevine. Dobiveni rezultati koristeni su za ocjenu seizmicke otpornosti građevine pomocu metode postupnog guranja, uz primjenu pristupa katnog mehanizma i mehanizma globalnog odziva. Prihvatljivije vrste injekcijskih smjesa usporedive su s cementnim injekcijskim smjesama. Dobiveno je da se pristupom globalnog odziva postižu realniji rezultati cak i kod niskih zidanih građevina

Most of the historical masonry buildings in Slovenia were built out of local stone or stone and brick with lime-based mortars. An efficient technique for improving the mechanical properties of stone or stone-brick walls is grout injection. In order to evaluate the quality and compatibility of commercially available injection grouts with materials present in historical masonry buildings, several types of hydraulic lime-pozzolana, lime-cement and cement grouts were tested. Chemical, physical and mechanical criteria to select optimal grout mixture for strengthening of historical masonry buildings were proposed, by which tested grouts were classified in three quality classes A, B and C. Only two commercial lime-cement grouts and one cement grout were able to meet the set requirements and were qualified in class B as medium quality grout (one lime-cement grout) or in class C as low quality grouts. Therefore, the design of hydrated lime-based grouts was carried out in continuation of our study, in order to obtain a grout that is highly compatible with the historical masonry in Slovenia. Among available limes, hydrated lime in powdered state and lime putty were used. Ground granulated blast furnace slag (GGBS), volcanic tuff, and limestone powder were used as mineral additives. It was found that the added combination of limestone powder and supplementary cementitious material (GGBS or tuff) has a beneficial influence on the properties of designed grout compositions.

The paper deals with time-dependent increase of compressive strength, splitting tensile strength and modulus of elasticity as well as with compressive stress-strain curves of self-compacting concrete (SCC) made with crushed limestone aggregate and high content of limestone filler. The characteristics under consideration were tested at the ages of 1, 3, 7, 28, 180, 360 and 720 days. Time evolution of the strength characteristics and modulus of elasticity was estimated with analytical models given in European code Eurocode 2. The study revealed that the models can adequately predict time evolution of the SCC characteristics, when coefficient s in the models is equal to 0.17, 0.08 and 0.25 for compressive strength, tensile strength and modulus of elasticity, respectively. These values of coefficient s are quite different from the value 0.2 proposed by Eurocode 2 for used cement strength class.

The knowledge of the structural behaviour of existing masonry requires a multilevel approach, with proper application of different diagnostic and assessment methodologies. The paper presents successful application of the results of in-situ tests on modelling the behaviour of historical structures. In order to obtain reliable material parameters for the application of different numerical models, different test methodologies a combination of Destructive Tests (DT), Minor Destructive Tests (MDT) and Non-Destructive Tests (NDT) were performed. Following this, two different models were applied for the assessment of seismic resistance of Pišece Castle – structural element model (SEM) for non-linear seismic analysis and 3D finite element model (FEM) for linear analysis by means of modal response spectrum analysis. The results of numerical analysis provided valuable information of the loadbearing capacity of structures, their seismic resistance as well as possible causes for the observed crack patterns.