Types Of Limestone Research Articles

Study of the Properties of Blended Cements Containing Various Types of Slag Cements and Limestone Powder.

It is currently vital to use more environmentally friendly cementitious composites, such as blended slag-limestone cements. However, many properties of slag-limestone cements are not yet fully research, especially in regards to the effect of limestone properties on properties of mortars and concrete. In the research, three types of slag cements were mixed with two types of limestone to obtain multi-component slag-limestone cements. Tests of rheological properties, heat of hydration, and compressive strength were conducted to ascertain the effect of limestone on the cement properties and to check the viability of this type of cement for engineering practice. It was found that the addition of up to 10% of limestone to slag cements did not have negative effects on tested properties; however, the exact influence of limestone was dependent on limestone particle size distribution. Increasing the amount of limestone in limestone-slag cements to 15% significantly decreased the compressive strength of the mortars and decreased hydration heat but had no significant effect on rheological properties.

The susceptibility to degradation of stone materials used in the built heritage of the Ortygia island (Syracuse, Italy): A laboratory study

Syracuse and the other cities of the Hyblaean area (in south-eastern Sicily) are characterized by a close relationship between building stone and geological context, since the wide use of local calcarenites characterized and defined their urban planning and architecture. In this paper, we discuss the results of a research aimed at investigating four types of limestone used in the built heritage of Ortygia, the historic city centre of Syracuse (in south-eastern Sicily). Specifically, the following carbonate stones have been investigated: 1) Syracuse limestone and 2) Melilli limestone, from the Monti Climiti Fm., 3) Oolitic limestone from the Monte Carrubba Fm., and 4) Giuggiulena limestone from the Pleistocene Panchina. All lithotypes underwent several mineralogical-petrographic and physical-mechanical investigations to individuate the causes responsible for their different durability when placed in the outdoor environment. Results obtained were also compared with literature data concerning the other two limestones employed as building and decorative materials in the façades of historic buildings in Ortygia, precisely the “Noto limestone” and the “Lumachelle limestone”, previously studied by other authors. Results achieved are consistent with deterioration types macroscopically observed in the monuments, and highlight the close relationship between compositional, textural, physical and mechanical characteristics of the stone and its specific damage.

Theoretical damage characterisation and damage evolution process of intact rocks based on linear energy dissipation law under uniaxial compression

The investigation of rock damage behaviour is an important requirement for ensuring stability control and safety prediction in rock engineering. In this study, based on the linear energy dissipation law and energy dissipation coefficient, a theoretical method is introduced for characterising the damage of intact rocks under uniaxial compression conditions. The existing uniaxial compression test data of 14 kinds of rock materials (including 6 types of granite , 4 types of sandstone , 2 types of marble, 1 type of slate, and 1 type of limestone) were used to verify the effectiveness of the damage characterization method. The results indicate that the damage evolution process of rocks under uniaxial compression can be fully expressed by the proposed theoretical damage characterisation method, and the damage variable exhibits a quadratic functional relationship with the loading stress level. Moreover, with the linear energy storage law serving as a theoretical basis, the peak dissipated strain energy in a rock damage expression under uniaxial compression can be accurately calculated. The new theoretical damage characterisation method overcomes the shortcomings of conventional damage characterisation methods (e.g. estimating the peak dissipated strain energy through a hypothesis), and provides a new means for analysing rock damage from an energy viewpoint.

Correlation between various mechanical properties of porous limestones from Hungary

This study focuses on the mechanical parameters of Miocene limestones from Hungary. Four different lithotypes of porous limestone from two localities were analysed in laboratory conditions. These lithologies have been widely used for centuries as construction material in Central Europe. One type of the Badenian Leithakalk limestone, which is a bioclastic grainstone containing molluscs, foraminifera and Lithothamnium and three types of Sarmatian porous limestone; a fine-grained, medium-grained and a coarse-grained bioclastic lithotype were compared in laboratory conditions. Bulk density, water absorption, apparent porosity, uniaxial compressive and tensile strength tests were performed to obtain data set for correlation analysis. With water saturation under atmospheric pressure, the uniaxial compressive strength and tensile strength of all studied lithotypes were reduced significantly. A good correlation between dry bulk density and apparent porosity was found for two lithotypes; meanwhile, for the two other lithotypes a less significant relationship was found. Bulk density correlates with uniaxial compressive strength and with tensile strength for all lithologies. However, a significant difference was found in the coefficients of determination of the different lithotypes. The coefficients in air-dry conditions were over 70%, but they became smaller after water saturation. According to these results, microstructure, porosity, and water saturation influence porous limestones’ damage mechanism.

The Major Controlling Factors and Different Oolitic Shoal Reservoir Characteristics of the Triassic Feixianguan Formation, Eastern Longgang Area, NE Sichuan Basin, SW China

AbstractBased on comprehensive analyses of occurrence, petrological observation, pore structure and geochemistry, the different reservoir characteristics and reservoir evolutionary pathways between different oolitic shoal reservoir types of the Feixianguan Formation on the west side of the Kaijiang‐Liangping Trough have been studied. There exist three stages of high‐energy slope break belts in the Feixianguan period, the corresponding three stages of oolitic shoals gradually migrating in the direction of the trough. Three types of oolitic shoal reservoirs, namely, residual‐oolitic dolomite, mold‐oolitic dolomite and sparry oolitic limestone, were formed during sedimentary‐diagenetic evolution, the pore types being intergranular dissolved pore, mold pore (or intragranular dissolved pore) and residual intergranular pore, respectively. The petrology, physical properties and pore structure of the different types of oolitic shoal reservoirs are quite different. Residual‐oolitic dolomite reservoirs have the best quality, while sparry oolitic limestone reservoirs have the poorest. Combined with analyses of trace elements, rare earth elements and carbon‐oxygen isotopes, it is suggested that the formation of residual‐oolitic dolomite reservoirs is jointly controlled by penesaline seawater seepage‐reflux dolomitization and hydrothermal dolomitization. Mold‐pore oolitic dolomite reservoirs are controlled by penesaline seawater seepage‐reflux dolomitization and meteoric water solution. The burial dissolution of organic acid not only further improves the reservoir qualities of previously formed oolitic dolomite reservoirs, but also preserves residual intergranular pores in the sparry oolitic limestone reservoirs.

A contribution to understand the Portuguese emblematic Ançã limestone bioreceptivity to fungal colonization and biodeterioration

• Portuguese Ançã limestone bioreceptivity to fungal colonization analysis. • Penicillia growth is favored in copiotrophic environments. • Aspergilli and Aeminium ludgeri growth is only slightly superior in oligotrophic environments. • After one-year incubation period all fungal species produced alterations. • Aspergillus westerdijkiae induced calcium carbonate mineralization. Fungal deteriorative action on historical stone objects often leads to important and incalculable cultural heritage losses. The Ançã stone is a unique limestone type widely used in some of the most important and emblematic Portuguese monuments. Being a soft and porous calcium carbonate limestone, this substrate is known to have a significant bioreceptivity to microbial colonization often resulting in notorious biodeterioration. Nonetheless, fungal bioreceptivity and biodeterioration of this lithotype remains scarcely characterized. With this in mind, the main aims of this work were to evaluate these aspects in a controlled laboratory environment. Inoculation of several fungal species in stone replicas revealed that Penicillia growth occupied larger areas under rich micro-nutrient environments, while Aspergilli and the black fungal species Aeminium ludgeri only denoted a slightly more accentuated growth under depleted nutrient conditions. Moreover, all species produced noticeable aesthetic alterations. In addition, we were able to verify A. ludgeri endolithic growth, Aspergillus glaucus putative hyphae penetration into calcite layers and mineralization phenomena occurring around A. westerdijkiae hyphae. By itself, this study provides a key update regarding fungal biodeterioration of this ancient, emblematic and remarkable limestone.

ASSESSMENT OF DETERIORATION PROCESS IN EXPOSED CARVED LIMESTONE FALSE DOOR OF ABUSIR ARCHAEOLOGICAL AREA

Carved limestone false door dating back to the late Sixth Dynasty or the First Intermediate Period in Abusir archaeological area suffers from many physiochemical and mechanical deterioration factors, which lead to various deterioration phenomena, such as distort the carvings, decorations, the disappearance of paint, cracks in different depths, and salt calcification. It was found in the fill of Shaft 5 in the tomb AS 79 at Abusir South, Excav. No. 9/AS79/2015 and located in the storeroom of Czech Excavation in Abusir area. The current work aims to study the type of limestone which the false door is made of, and to know if there were colors on the false door or not, also to know if there were deterioration mechanisms that affect the carved limestone false doors of Abusir to evaluate the deterioration ratio in stone structure and the effects of surrounding environmental factors on stone. The investigation and characterization processes of archaeological limestone samples were carried out by polarizing microscopy (PLM), optical microscopy (OM), scanning electron microscopy (SEM-EDX) micro-analysis system, X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier transform infrared spectroscopy (FTIR). The results revealed that the limestone material of the false door belongs to micrite limestone with very fine grains and needs to be conserved.

An Experimental Investigation of the Influence of Loading Rate on Rock Tensile Strength and Split Fracture Surface Morphology

To investigate the effect of the loading rate on the tensile strength of rock material and the morphology of the resulting split fracture surfaces, three types of rock specimens, namely, granite, basalt and limestone, were collected and tested with Brazilian testing under different loading rates. The tensile strength was measured, and the effect of the loading rate on the tensile strength of the rock material was studied. Digital terrain map models of the split fracture surface were obtained with an optical 3D scanning technique, and the effects of the loading rate on the geometry and morphology of the fracture surface were studied. The influence of the loading rate and tensile strength on the roughness was studied quantitatively by calculating the roughness indices of a fracture surface for all three kinds of rock. The research results show that the rock tensile strength increases with the loading rate. A linear relationship was established in double-logarithmic coordinates to describe the relationship between the tensile strength and the loading rate. Four different roughness indices were used to describe the morphology of the split fracture surface. The analysis results show that the magnitudes of all the roughness indices increase with the loading rate. Additionally, the roughness indices for all three types of rock linearly increase with the tensile strength. This linear trend indicates that it is possible to utilize fracture surface roughness indices to estimate rock tensile strength. The current study may motivate further research on the relationship between the morphology indices of rock fractures and mechanical parameters of the rock.

In Situ Investigation of Fluid‐Rock Interactions at Ångstrom Resolution

AbstractThe flow of aqueous phases through porous media shapes the world. It changes the courses of rivers, erodes mountainsides, dissolves historical monuments, builds caves, regulates the carbon cycle, and changes porosity in aquifers and hydrocarbon reservoirs. Despite the significance of this process both to natural phenomena and human endeavors, fundamental insight into the mechanisms that drive it at the Ångstrom scale is scarce. Here, we employ environmental transmission electron microscopy (ETEM) to visualize interactions between water and various types of porous media, including sandstone, limestone, and dolostone samples, at Ångstrom resolution in real time. Unlike other techniques presented in the literature, ETEM allows for direct visualization of both the aqueous phase and the porous media. As expected, dissolution and recrystallization were observed to significantly impact the shapes, sizes, and interconnectivities of the pores in the rocks. However, for the first time, we provide direct in situ experimental evidence that adsorption‐induced strain can also significantly impact the above‐mentioned parameters, especially in micropores. In some cases, adsorption was observed to reduce effective pore size by more than 60%. The magnitude of the change in pore size was found to vary with pore wall mineralogy and pore geometry. This work presents the first direct Ångstrom‐resolution observations of liquid adsorption films and adsorption‐induced strain.

Strategies for the promotion and sustainable growth of nature tourism in the Town of Tibaná

Nowadays, sustainable tourism has increased notably, becoming a transversal task that allows the integration ofdifferent economic activities in this region, contributing to economic growth. In this article, the authors seek to identifysome strategies to promote the growth of nature tourism without affecting the landscape and biotic systems found inTibana (Boyaca), since this town has a great natural and cultural potential due to the fact that it has a wide rural territorypreserving its roots and customs characteristic of the region. The population carries out natural tourism in an informalway, carrying out tours of natural trails, which are in the management stage for the appropriate regulation, with actionsto minimize the environmental impact with a suitable use of resources To determine the possible strategies, we did some tours with inhabitants of the municipality, taking advantage of the factthat they know the soil and the routes of the most important trails, achieving the survey of geographical information,characterization of the flora and fauna of the area, which contribute to generating different results, regarding the geologyof Tibana. It was found that it has soil formations based on clay and different types of limestone, determining a maximumnumber of people who can visit the trail, training was also carried out with the different tourism actors addressing issuessuch as logistics, resources optimization, strategic planning, as well as association workshops, among others that allowto start the process of formation of tour operators

CO2 Capture for Dry Reforming of Natural Gas: Performance and Process Modeling of Calcium Carbonate Looping Using Acid Based CaCO3 Sorbent

Several industrial activities often result in the emissions of greenhouse gases such as carbon dioxide and methane (a principal component of natural gas). In order to mitigate the effects of these greenhouse gases, CO2 can be captured, stored and utilized for the dry reforming of methane. Various CO2 capture techniques have been investigated in the past decades. This study investigated the performance and process modeling of CO2 capture through calcium carbonate looping (CCL) using local (Malaysia) limestone as the sorbent. The original limestone was compared with two types of oxalic acid-treated limestone, with and without aluminum oxide (Al2O3) as supporting material. The comparison was in terms of CO2 uptake capacity and performance in a fluidized bed reactor system. From the results, it was shown that the oxalic acid-treated limestone without Al2O3 had the largest surface area, highest CO2 uptake capacity and highest mass attrition resistance, compared with other sorbents. The sorbent kinetic study was used to design, using an Aspen Plus simulator, a CCL process that was integrated with a 700 MWe coal-fired power plant from Malaysia. The findings showed that, with added capital and operation costs due to the CCL process, the specific CO2 emission of the existing plant was significantly reduced from 909 to 99.7 kg/MWh.

Investigation of blasting impact on limestone of varying quality using FEA

Large deformation and rapid pressure propagation take place inside the rock mass under the dynamic loads caused by the explosives, on quarry faces in order to extract aggregate material. The complexity of the science of rock blasting is due to a number of factors that affect the phenomenon. However, blasting engineering computations could be facilitated by innovative software algorithms in order to determine the results of the violent explosion, since field experiments are particularly difficult to be conducted. The present research focuses on the design of a Finite Element Analysis (FEA) code, for investigating in detail the behavior of limestone under the blasting effect of Ammonium Nitrate & Fuel Oil (ANFO). Specifically, the manuscript presents the FEA models and the relevant transient analysis results, simulating the blasting process for three types of limestone, ranging from poor to very good quality. The Finite Element code was developed by applying the Jones-Wilkins-Lee (JWL) equation of state to describe the thermodynamic state of ANFO and the pressure dependent Drucker-Prager failure criterion to define the limestone plasticity behavior, under blasting induced, high rate stress. A progressive damage model was also used in order to define the stiffness degradation and destruction of the material. This paper performs a comparative analysis and quantifies the phenomena regarding pressure, stress distribution and energy balance, for three types of limestone. The ultimate goal of this research is to provide an answer for a number of scientific questions, considering various phenomena taking place during the explosion event, using advanced computational tools.

Correction of soil acidity with shell lime and dolomitic limestone in a Latossolo Vermelho distrófico in Paraná state, Brazil

Soil acidity is a limiting factor for agricultural production, and the correction is carried out by liming, with the variable response with characteristics of the soil and the source used. The study aimed to analyze the effect of liming on a Latossolo Vermelho distrófico (stands for the oxisols in soil taxonomy and Ferralsols in WRB-FAO). The experiment was conducted in a completely randomized design in a 2x2x3 factorial scheme, with two soil textures (medium and clayey), two types of limestone (dolomitic and shell), and three soil cover conditions (without cover, with corn residues, and with soy residues). Liming carried out considering the chemical characteristics of the soil, the neutralization power of the sources, and the quantity determined by the base saturation method. The data were submitted to analyses of variance, and the means were compared by the Scott-Knott test, with 5% significance. The acidity correction occurred in less time in clayey soil. The coverage on the soil surface influenced the acidity correction, with a dynamic response concerning the analyzed conditions. Shell and dolomitic lime showed adequate efficiency in correcting acidity in both soil textures, with non-standard differences in conditions.

The effect of bedrock and species mixture on wood density and radial wood increment in pubescent oak and black pine

Wood density and radial wood increment were examined in trees of pubescent oak (Quercus pubescens Willd.) and black pine (Pinus nigra Arnold., subsp. nigra) in relation to stand mixture and underlying bedrock. Trees of both species from pure and mixed stands were sampled across two types of bedrock, limestone and flysch. Trees from each species were similar in age. Wood density was estimated in standing trees using resistance drilling and increment cores were taken from a smaller subsample of trees of both species. Tree-ring, earlywood and latewood widths were measured and compared to radial profiles of wood density. The influence of stand mixture, diameter at breast height and bedrock on wood density was examined using a Bayesian general linear model. Wood density was significantly higher in pubescent oak than in black pine. Stand mixture was found to affect wood density positively, although the magnitude of the effect was relatively small when compared to other influencing factors also included in the current study. The effect of diameter on wood density was positive on both bedrocks in pubescent oak and negative or neutral in black pine. The size of the effect varied by bedrock and species. On flysch bedrock, the influence of diameter on wood density was stronger than it was on limestone. These indirect bedrock effects on wood density are probably a result of different soil fertility rather than the bedrock itself. There was a notable difference in radial wood increment in both species across the two bedrocks, whereas the differences in densities were smaller. Higher wood densities found on flysch in the subsample of pubescent oaks are likely an effect of higher proportions of latewood, while the opposite trend was observed in black pine. Higher wood density was found on limestone in black pine despite higher latewood percentages on flysch. In the context of forest management, the species composition of the naturally occurring mixtures in the sub-Mediterranean region should be adjusted slightly to favor pubescent oak, since it is a climax species and will bind more carbon for longer than black pine due to higher wood densities. Future forest management should also promote the overall development of pubescent oak trees in sub-Mediterranean stands. The results are especially important in the European context, because the share of sub-Mediterranean stands is expected to rise with global warming.

Pore Structure and Water Transfer in Pietra d’Aspra Limestone: A Neutronographic Study

Neutron radiography (NR) was here applied to study the effects of two different commercially available consolidants on the water absorption properties in a particular type of limestone (biocalcarenite), known as Pietra d’Aspra stone, which is one of the most extensively used lithotypes in Sicilian Baroque buildings. Our attention was mainly focused on the evaluation, using a fast and nondestructive visualization of water motion through capillarity, of the effectiveness of such layers as consolidating agents in view of preserving and maintaining both old and modern structures. The biocalcarenite was treated with nanosilica (Nano Estel®) and nanolime (CaLoSil®) by brushing it until full saturation, and then artificially weathered by salt crystallization and temperature/relative humidity jumps. Liquid distribution and height of the water front were monitored as a function of time. Significant differences in the water suction behavior among all the investigated samples were highlighted, which allowed us to gain insight into the coating/substrate interaction mechanisms which regulate the fluid mobility inside the porous network of the limestone.

Research on some effective properties in nomination of Urfa Limestone to the “Global Heritage Stone Resource” designation

Extracted from Şanliurfa Province in Turkey, Urfa limestone is one of the limestone types that can be nominated to Global Heritage Stone Resource (GHSR). It has been used since the Neolithic Period (i.e., approximately 12,000 years ago) in world-renowned Gobekli Tepe Cultural Center in Urfa. In this study, a research has been conducted on the candidacy potential of Urfa limestone for Global Heritage Stone Resource (GHSR). Urfa limestone, which was used as a building block as of the Neolithic Period and in the first temple built in Anatolia, was also the building block of Gobekli Tepe. The use of Urfa limestone in Sogmatar Ancient City (second century AD), Şuayb City, Harran Ulu Mosque, Urfa Ulu Mosque (St. Stephan Church), Reji Church, sculptures, and Şanliurfa’s traditional city texture in houses, inns, castles, walls, gates, and bridge structures was investigated along with the use in Gobekli Tepe. The use of Urfa limestone in historical buildings and today’s buildings was investigated along with the use in Gobekli Tepe. The engineering characteristics of the building blocks in which Gobekli Tepe was built were examined. A series of engineering characterization tests and analyses were made on the building block samples regarding mineralogical and petrographic properties (polarize microscope, XRD, and SEM), and chemical (XRF), physico-mechanical, petrophysical, and insulation properties (TG and DTA analysis). Urfa limestone is in crystallized form and has a sparite texture containing 55.86% CaO and 0.36% SiO2. The Δ (change of characteristics in percentages) values in petrophysical characteristics were between 1.23 and 18.72%, and the Δ values after salt crystallization test were between 3.78 and 31.67%. According to this characteristics change (Δ%), it is more resistant to degradation compared with other natural stones originating from calcium carbonate. According to SEM Analysis, it was determined that it has a high insulation characteristic in the structure of Urfa limestone because it is contactless among pores. The usage performance of Urfa limestone in Gobekli Tepe, and in historical buildings and today’s buildings has been proven to be good according to engineering characterization tests. Urfa limestone fulfills all requirements for Global Heritage Stone Resource (GHSR) designation.

HIGH RESOLUTION BIOSTRATIGRAPHIC ANALYSIS OF THE DANIAN STAGE, PER FAT SECTION, DUHOK AREA, KURDISTAN REGION, NORTH OF IRAQ

The occurrence of the Danian Stage at Kurdistan Region of Iraq, particularly in the high folded zone, was a debatable subject by many authors. Most of the previous studies believe that it is poorly preserved. This study reviews the Danian sequence at Per Fat of Duhok area using high resolution biostratigraphic analysis of the planktic foraminifera. The Danian stage sequence in the studied locality is represented by the marlstone, shale, and marly limestone rock types of the Aaliji Formation. Occasional iron oxides and microscopic glauconites intervals are characteristics. The thickness of the Danian sequence is about 29.71 m. The sequence is underlined by the Upper Cretaceous Shiranish Formation, and overlies by the green-olive clastic sediments of the Paleocene Kolosh Formation. Biostratigraphic zonation of the identified foraminiferal assemblages shows the occurrence of the four Danian Planktic foraminiferal biozones and three subzones including Guembelitria cretacea partial-range zone (P0); Parvularugoglobigerina eugubina total range zone (Pα); Parasubbotina pseudobulloides partial-range zone (P1); Globanomalina archaeocompressa partial-range subzone (P1a), Subbotina triloculinoides interval subzone (P1b), Globanomalina compressa-Praemurica inconstans interval subzone (P1c); and Praemurica uncinata interval zone (P2). This indicates a complete sequence of the Danian stage is preserved in the Per Fat section of Duhok area.

Electrical resistivity survey data for potential aquifer in Banggi Island, Sabah, Malaysia.

The survey data on potential aquifer was collected at two sites located in Banggi Island (i.e. Laksian Primary School [LPS] and Padang Primary School [PPS]), Malaysia on 25 and 26 April 2013. Both locations are geologically surrounded by various types of lithologies, namely, sandstone, mudstone, siltstone, shale, chert, conglomerate, lignite, tuff, limestone, terrace sand, gravel and coral. The resistivity data consisted of six-line pole-dipole short arrays and were recorded in-situ using SAS 4000 ABEM Lund Imaging System, together with a relay switching unit (Electrode Selector ES 464), six multiconductor cables, steel rod electrodes and jumpers. The data, namely electrode spacing, depth of investigation, subsurface resistivity, type of material and horizontal data coverage were used to assess the characteristics of the potential aquifer. The recorded data were then processed using RES2DINV software to obtain 2-D inversion model of the subsurface. The data were also equipped with six models of inverse resistivity section for both areas. The data obtained can be used by the government and stakeholders for groundwater exploration and extraction in order to provide water supplies for local communities, especially since access to these resources from the surrounding water treatment plants on the island is limited.

Evaluation of Point Load Test Effectiveness in Estimation of Long-Term Durability of Some Chinese Limestone Rocks Due to Frost Action

In spite of point load method has been frequently used for assessment of the decay state of stones under weathering agents, its method in estimation of long-term durability of natural rocks remains limited. This study aims to assess the point load method efficiency in evaluation of long-term durability of limestone types due to frost action. For this reason, the frost process up to 100 cycles was applied on different limestone types which quarried from mine in China and the ultrasound properties including compressional wave velocity (Vp) and spatial attenuation (αs) were determined before and after frost cycles and then their variation rates were obtained. The variation rates of Vp and αs including ΔVp and Δαs, respectively, were taken into consideration as a function of the decay state of stones and as indicators of the frost durability action. The results indicated that there are a strong correlations between point load index values (σp) and ΔVp and Δαs with R2 of 0.79 and 0.82, respectively. It was found that the point load method is an effective tool for evaluating the long-term durability of rocks and can be used for a fast and on-field assessment of long-term durability of stones especially at different mine faces. Therefore, it can facilitate the choosing of a highly durable stones for different outdoor applications. Further, the point load index values can be used to make a new classification of rock strength depending on their durability.

Evaluating the protecting effects of two consolidants applied on Pietra di Lecce limestone: A neutronographic study

Abstract In this work a combined laboratory-based and neutronographic investigation was carried out on a type of limestone, known as Pietra di Lecce stone, widely used in Italian Baroque as construction material. The limestone was treated with two different commercially-available coatings, namely nanosilica and nanolime, and artificially weathered by salt crystallization and temperature/relative humidity jumps. The aim was to provide an experimental evidence of the protective and consolidating effectiveness of the two treatments by looking at the water absorption process occurring inside the pore network of the analyzed stones. The analysis of the wetting front position revealed significant variations in the water absorption kinetics among the investigated samples, suggesting different mechanisms of interaction between the inorganic consolidants and the underlying bulk stone. Finally, a quantitative evaluation of the best effectiveness of the two products was addressed, particularly useful in view of an appropriate choice of restoration procedures to be applied to building materials.