Papers by Roman Kozlowski
Studies in Conservation, 2007
The monitoring of acoustic emission (AE) has allowed direct tracing of the fracturing intensity i... more The monitoring of acoustic emission (AE) has allowed direct tracing of the fracturing intensity in wooden cultural objects exposed to variations in temperature (T) and relative humidity (RH). High-frequency components produced by the mechanical fracturing were extracted from the raw AE signals using the wavelet transforms. The accumulated energy of these components depended on the magnitude and rate of the RH variations. The AE activity became negligible below the allowable magnitude for the rapid RH variation established by numerical modelling, or when the time interval allowed for the RH variation was long enough. On-site AE monitoring of a wooden altarpiece in a historic church further confirmed the usefulness of the technique in tracing climate-induced stress in wood. The development of practical AE sensors to indicate risk to wooden objects in museums and at historic sites, or during their transportation, is discussed.
Journal of Cultural Heritage, 2010
The European project FRIENDLY-HEATING: comfortable to people and compatible with conservation of ... more The European project FRIENDLY-HEATING: comfortable to people and compatible with conservation of artworks preserved in churches addressed the problems caused by the continuous or intermittent heating of historic churches, which disturbs the microclimatic conditions to which the building and the artworks preserved inside have acclimatised. As thermal comfort and the preservation of artworks often conflict with each other, a balance between the two needs is necessary. The proposed heating strategy is to provide a small amount of heat directly to people in the pew area while leaving the conditions in the church, as a whole, undisturbed. This novel heating system is based on some low-temperature radiant emitters mounted in a pew to provide a desirable distribution of heat to the feet, legs and hands of people occupying it. Due to little heat dispersion, this novel system not only significantly reduces the risk of mechanical stress in wooden artworks and panel or canvas paintings, fresco soiling and cyclic dissolution-recrystallization of soluble salts in the masonry, but is energy-efficient. The detailed environmental monitoring was conducted in the church of Santa Maria Maddalena in Rocca Pietore, Italy over a 3-year period to verify the performance of the novel heating system in comparison to the warm-air system that was active earlier in the church. The methodology and results of this comprehensive and multidisciplinary study were included in three draft standards of the European Committee for Standardisation intended for use in the study and control of environments of cultural heritage objects.
Procede utilise pour proteger un materiau poreux sensible a la corrosion provoquee par des agents... more Procede utilise pour proteger un materiau poreux sensible a la corrosion provoquee par des agents polluants presents dans l'atmosphere. Dans ce procede on traite la surface du materiau avec un agent renfermant plus de 90 % en poids de sol de dioxyde de silicium. Cette invention concerne egalement un materiau de construction poreux constitue d'une couche de sol de dioxyde de silicium gelifie situee dans les pores existant sous la surface du materiau.
Journal of the Chemical Society, Chemical Communications, 1983
Extended X-ray absorption fine structure (EXAFS) studies beyond the vanadium K-edge of supported ... more Extended X-ray absorption fine structure (EXAFS) studies beyond the vanadium K-edge of supported V 2 0 5 catalysts show that the catalytically active surface phase supported on anatase is not in epitactic registry with the T i 0 2 but is in a state of structural disorder.
Materials, Technologies and Practice in Historic Heritage Structures, 2010
Highly hydraulic binders, known as natural or Roman cements, were key materials for the economic ... more Highly hydraulic binders, known as natural or Roman cements, were key materials for the economic and easy manufacture of stuccoes for the exterior of buildings during the nineteenth and early twentieth centuries. Roman cements were produced by burning naturally occurring deposits of calcium carbonate rich in clay minerals. They were distinguished from other hydraulic binders principally by a very short setting time, agreeable texture and colour, little shrinkage on setting and excellent weather-resistance. They were first produced in England in 1796 when James Parker patented a cement known as Parker's or Roman cement (Parker 1796). The material was obtained by firing clay-bearing calcareous nodules found in the London clay beds on the Isle of Sheppey, England. Despite implied links to the Roman binders, Parker's 'Roman cement' was a true hydraulic cement very different from the hydraulic binders used by the Romans in which pozzolanic materials, not cementitious in themselves, had combined with lime in the presence of water to form insoluble compounds possessing cementing properties. The Roman cement mortars were mainly used in construction where masonry was subjected to moisture and high levels of strength and durability were needed. The manufacturing of Roman cement developed in mainland Europe after 1850. In contrast to England, where cements were largely produced from the nodules, marls were the usual source.
Studies in Conservation, 1990
Three lithological factors were identified as controlling the durability of the porous limestone ... more Three lithological factors were identified as controlling the durability of the porous limestone from Pinczów. Coarse-grained texture, high crystallinity and lack of quartz give good weathering resistance to the stone. Gypsum formation deep within the stone fabric is the ...
Materials Characterization, 2007
As a part of a major study on 19th century Roman cements a laboratory optimisation study of the c... more As a part of a major study on 19th century Roman cements a laboratory optimisation study of the calcination of two marls has been conducted within the temperature range 730 to 1100 °C. Strength assessment has shown that the optimum kiln conditions lie towards lower temperatures and differ for the two marls by no more than some 50 °C. This paper discusses the clinker properties in terms of phase composition and microstructural features. The textural and mineralogical characteristics of the marl fractions significantly influence the nature and amount of phases formed during solid-state reactions under non-equilibrium conditions. At low to intermediate calcination temperatures it is mainly the fine-grained matrix of the marls which reacts, while coarse particles remain largely un-reacted. The major reactive crystalline phases identified in the optimum cements are belite in two polymorphs and free lime, while a number of other compounds remain unclear because of their non-crystalline nature.
Journal of ASTM International, 2007
Forming an important binder material in 19th century construction and facade decoration of many E... more Forming an important binder material in 19th century construction and facade decoration of many European cities and towns, natural cements calcined at low temperatures are called Roman cements. Roman cement mortars generally appear well preserved. A number of samples from historic buildings were collected and analyzed in order to understand their range of composition and properties. Scanning electron microscopy and other microscopic techniques were employed, along with the assessment of physico-mechanical properties. A wide range of differently calcined clinker relicts within each mortar is shown by the study to be the most significant feature of Roman cement mortars. These unreactive particles, classified as being either overfired or underfired, play an important role for the mortar properties, obviously. The binder relicts are composed of a number of phases in the system Ca-Si-Al-Fe. C sub 2 S and C sub 2 AS (gehlenite) are among the most frequent compounds, their grain size and microstructure depending on calcination temperatures. Clinkers produced at lower temperatures, in particular, show nonequilibrium features such as solid solution systems and zoning by partial diffusion. A wide range of mineralogical compositions reflecting local geological conditions is covered by the aggregates found in the mortars. Cast and in situ applied mortars differ in the amount of aggregate, which is generally lower for cast elements. No correlation exists between the amount of inert material and the state of preservation indicated; such as, by the occurrence of shrinkage cracks. High compressive strengths are shown by historic cast mortars at comparably low moduli of elasticity. Frequently the total porosity is high. The above-mentioned properties are presented in this paper, as well as a discussion of them in terms of the historic Roman cement mortar's excellent aging performance.
Journal of ASTM International, 2007
ABSTRACT No Hydration of five Roman and American natural cements was analyzed using X-ray diffrac... more ABSTRACT No Hydration of five Roman and American natural cements was analyzed using X-ray diffraction, mercury intrusion porosimetry, and scanning electron microscopy of cement pastes. Two cements were prepared in the laboratory by burning marls from geological sources in Poland (Folwark) and Austria (Lilienfeld). The selection of raw materials and burning conditions were optimized so that the hydraulic nature and appearance of the final burnt materials matched as closely as possible historic Roman cements widely used in the 19th and the beginning of the 20th centuries in Europe to decorate buildings. Three other cements are produced commercially: quick setting Prompt cement from Vicat, France, and Rosendale cements from Edison Coatings Inc., USA. The hydration of the cements studied was shown to comprise two distinct stages. The immediate setting and early strength is due to the formation of calcium aluminum oxide carbonate (or sulfate) hydroxide hydrates. The development of long-term strength is brought about by the formation of calcium silicate hydrates. Similarities and differences between the individual cements are discussed.
Cement and Concrete Research, 2009
Roman cement was a major material used in the architecture of the nineteenth and early twentieth ... more Roman cement was a major material used in the architecture of the nineteenth and early twentieth century across Europe, until it was displaced by Portland cement, and is absent from the palette of materials from which conservationists may now select. Calcination of cementstones and marls from six sites in Poland, Austria and the UK has been conducted. The resulting mineralogy is dependant upon the characteristics of the original feedstock and the calcination temperatures. The principal hydraulic components are belites and amorphous aluminates. The stable belites in cements calcined at lower temperatures are largely α / C 2 S while β C 2 S is stabilised as the calcination temperature is increased. Other components include uncalcined remnants, lime, brownmillerite and gehlenite. Optimum cements, assessed by compressive strength, were produced at relatively low temperatures, typically in the region of 750 o C. Two strength development profiles have been observed.
Cement and Concrete Research, 2009
Mercury porosimetry, water vapour and nitrogen adsorption were used to follow the hydration of Ro... more Mercury porosimetry, water vapour and nitrogen adsorption were used to follow the hydration of Roman cements-belite cements calcined at low temperature. Generally, unimodal distribution of pore sizes was observed, with the threshold pore width decreasing considerably with increasing curing time. An open porous structure with the threshold pore diameter between 0.2-0.8 µm and the specific surface area not exceeding 20 m 2 /g was produced at early ages when quick growth of the C-A-H phases is observed. The surface area reached up to 120 m 2 /g and the threshold pore width shifted to around 0.02 µm when the subsequent formation of C-S-H gel filled the larger pores. Both mercury porosimetry and water vapour adsorption were found to be capable of following the progress of hydration of the Roman cements with high reliability at least for a comparative evaluation of historic Roman cement mortars and repair materials used in restoration projects.
Archeion, 2021
Budynek archiwum państwowego to miejsce służące przede wszystkim długoterminowej ochronie materia... more Budynek archiwum państwowego to miejsce służące przede wszystkim długoterminowej ochronie materiałów archiwalnych. Musi także spełniać wymagania stawiane przyjaznej instytucji publicznej, związane z obsługą i zaspokajaniem różnorodnych potrzeb użytkowników w zakresie działalności prowadzonej przez archiwa. Pełnione przez archiwa funkcje determinują, już na etapie opracowywania koncepcji, a następnie dokumentacji projektowej, kwestie konstrukcji, wyposażenia oraz zastosowanych instalacji i technologii. Szczególne znaczenie w przypadku archiwum państwowego mają pomieszczenia magazynowe, służące przechowywaniu materiałów archiwalnych. W wypadku nowej siedziby Archiwum Narodowego w Krakowie, dla ośmiokondygnacyjnego segmentu magazynowego opracowano koncepcję z pasywną regulacją klimatu. Jest on wyodrębnioną strukturą, w której nie ma stałych stanowisk pracy, a pasywną stabilizację mikroklimatu zapewniono w znacznym stopniu przez przemyślane rozwiązania budowlane: dobrą izolację termiczn...
Strain, 2019
Sustainable management of cultural heritage collections requires tools that, on the one hand, qua... more Sustainable management of cultural heritage collections requires tools that, on the one hand, quantitatively relate risk of damage to environmental impacts and, on the other hand, can be easily used by conservation professionals and decision makers in heritage buildings or buildings housing collections. This paper explains how continual processing of ambient relative humidity (RH) data monitored in museums or historical buildings is used to assess quantitatively the climate-induced physical damage risk to art objects. The software continually decomposes RH data into a set of elementary sinusoidal RH fluctuations using discrete Fourier transform. The user needs to provide basic characterisation of objects in the collection. Then each elementary sinusoidal RH fluctuation is transformed, using the precalculated database, into an elementary strain fluctuation experienced by the object. The complete strain history is calculated by the superposition of all elementary strain fluctuations. The risk of damage can be assessed by comparing strain against a critical level selected-the damage criterion. Wooden panels have been selected to illustrate the approach, and its reliability was demonstrated by comparison with the strain versus time histories obtained by full finite element modelling. The proposed approach based on the analysis of moisture response of objects is significant progress to current practices of evaluating climate parameters themselves.
Studies in Conservation, 2018
HERIe is a web-based decision-supporting software tool to facilitate the management of collection... more HERIe is a web-based decision-supporting software tool to facilitate the management of collection environments by precise assessment of climate-induced risk of physical damage to vulnerable objects. The software translates the relative humidity and temperature data recorded in the environment of the analysed object into a strain history experienced by it, and estimates the risk of physical damage using selected failure criteria. As all information is pre-calculated for the user, no engagement in complex and time-consuming numerical simulations is required. HERIe is available for testing at herie.mnk.pl. Detailed information on the methodologies used by the software is available at the above website which also contains tutorial climates. The current work aims at refining HERIe by selecting the damage criteria not only from laboratory studies but also from direct monitoring damage accumulation in objects, especially using the acoustic emission method. The software has been expanded to include moisture-induced response of parchment to support managing environments in libraries and archives.
Building Simulation, 2016
The particle concentrations outside and inside two historical churches were monitored for at leas... more The particle concentrations outside and inside two historical churches were monitored for at least ten months. The highest levels of outdoor concentrations were recorded in winter. This was caused by high levels of particle emissions from the burning of predominantly solid fuel for domestic heating in premises around the two churches monitored. These high levels of particle concentrations declined over the warmer periods of the year with the lowest concentrations occurring in the summer months. Owing to the marked winter–summer pattern for outdoor concentrations, the particles of outdoor origin accounted for 80%–90% of the overall indoor particle concentrations in the period of predominantly cold weather conditions (December to March) and for 50%–60% in the warm period (June to September). Reducing air exchange between the external space and the church interiors by keeping windows and doors closed had a limited effect on the reduction of average particle concentrations indoors (by less than 10%). A controlled air exchange system, which would increase the ventilation of a church when the particle concentration outdoors is lower than indoors and reduce ventilation when the outdoor air is polluted, would produce a further reduction of 10% in the indoor average particle concentration. The general conclusion is that the protection of the interiors of historical churches against soiling is primarily achieved by the improved particle filtering capacity of building envelopes and the gradual reduction of the overall outdoor particle concentration. Use of air cleaning systems with particle filtration may be a viable long-term option.
Building and Environment, 2016
Abstract Particle sources and deposition inside two historical churches, differing in size and co... more Abstract Particle sources and deposition inside two historical churches, differing in size and construction were examined. The particle concentrations indoors and outdoors were monitored for at least 10 months. The air exchange rate (AER) was determined by fitting an exponential decay curve to the recorded concentration of indoor-generated CO 2 . The two-parameter mass balance equation, taking into account the particle sources and sinks in the indoor environment of churches, was used to determine the particle deposition velocities and penetration factors. Large indoor and outdoor particle concentration variability helped to separate the effects of penetration and deposition losses. For example, liturgical services regularly generated high indoor particle concentrations, owing to the burning of incense. During the particle concentration decay after the services, losses due to deposition could be reliably determined, whereas the events of high outdoor aerosol concentrations with no emission of particles indoors allowed the penetration factors to be precisely determined. The minimal AER values of 0.1 and 0.3 h −1 were observed in the closed brick and wooden church, respectively. Typically, area-averaged deposition velocities for particles of diameters 0.3–1 μm or above 1 μm were 1.5·10 −5 and 2.1·10 −5 m/s, respectively, and were very consistent between the two churches studied in spite of the differences in their design, size, construction materials and pattern of use. Penetration factors ranged from 0.7 to 0.86.
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Papers by Roman Kozlowski