Weathering Tests on Raw and Consolidated Vicenza Stone

: The preservation of cultural heritage, particularly historical stone structures, represents a very challenging matter due to several environmental and anthropogenic factors. Vicenza stone, a calcareous rock known for its historical significance and widespread use in architectural masterpieces, requires significant attention for conservation. In fact, as the demand for sustainable and effective preservation methods intensifies, the exploration of innovative consolidation strategies becomes essential. To this end, inorganic consolidants, based on alkaline silicate formulations and nano-silica, were explored for their promising performance in enhancing the surface properties and chemical stability of Vicenza stone. In particular, the durability of treated and untreated Vicenza stone samples was evaluated by means of accelerated weathering tests such as freeze-thaw cycles, salt crystallization and simulation of acid rain. The experimental results revealed that Vicenza stone is very resistant to the effects of freeze-thaw cycles and acid rain; both the accelerated weathering tests did not show significant differences between treated and untreated VS samples. A different behavior was detected for the test for resistance to salt crystallization, whose findings led us to deduce that, for this kind of degradation, it is possible to observe a more beneficial effect of the consolidation treatments on the stone durability

Mining Safety and Sustainability I

Safety and sustainability are becoming ever bigger challenges for the mining industry with the increasing depth of mining. It is of great significance to reduce the disaster risk of mining accidents, enhance the safety of mining operations, and improve the efficiency and sustainability of development of mineral resource. This book provides a platform to present new research and recent advances in the safety and sustainability of mining. More specifically, Mining Safety and Sustainability presents recent theoretical and experimental studies with a focus on safety mining, green mining, intelligent mining and mines, sustainable development, risk management of mines, ecological restoration of mines, mining methods and technologies, and damage monitoring and prediction. It will be further helpful to provide theoretical support and technical support for guiding the normative, green, safe, and sustainable development of the mining industry

Feasibility of Expanding the Use of Steel Slag as a Concrete Pavement Aggregate

Sustainability has become an important aspect of developed countries throughout the world. Sustainability is the ability to use byproducts and or waste materials from industry and recycle these materials in such a way that the application of the materials provides a beneficial use in the manufacturing or construction sector. As the United States and the rest of the world continue to grow, so too does the demand on the limited natural resources throughout the world. It is this demand on the resources that has brought the idea of sustainability to the forefront of research and design.The transportation industry continues to incorporate sustainability into its projects. The industry is constantly trying new and innovative ways to recycle materials that would otherwise be sent to a landfill. Slag, a byproduct from the production of steel, is one of these materials. The transportation sector has used slags as aggregates for subbase and base layers in roads. Some slags, like blast furnace slag, have been used in portland concrete cement (PCC) applications as well. The focus of this research is to investigate the feasibility of using steel slag as an aggregate for use in portland concrete cement.An important aspect of this research was to complete a comprehensive review of other research that has been conducted on the use of steel slag as an aggregate. The literature reviewed included of laboratory studies that focused on the physical, mechanical, chemical, and expansive characteristics of the steel slag. The research on the use of steel slag was gathered from 16 different countries, which include the United States, Spain, Japan, China, Germany, Finland, and Saudi Arabia. Some of these studies have found that properly treated slag may be non-expansive and used in PCC. The possible expansion of the steel slag is the most important characteristic. The expansion of the steel slag aggregate can have detrimental effects on a pavement. This research investigated some of the treatment processes that are being used to alter t

Feasibility of Expanding the Use of Steel Slag as a Concrete Pavement Aggregate

Sustainability has become an important aspect of developed countries throughout the world. Sustainability is the ability to use byproducts and or waste materials from industry and recycle these materials in such a way that the application of the materials provides a beneficial use in the manufacturing or construction sector. As the United States and the rest of the world continue to grow, so too does the demand on the limited natural resources throughout the world. It is this demand on the resources that has brought the idea of sustainability to the forefront of research and design.The transportation industry continues to incorporate sustainability into its projects. The industry is constantly trying new and innovative ways to recycle materials that would otherwise be sent to a landfill. Slag, a byproduct from the production of steel, is one of these materials. The transportation sector has used slags as aggregates for subbase and base layers in roads. Some slags, like blast furnace slag, have been used in portland concrete cement (PCC) applications as well. The focus of this research is to investigate the feasibility of using steel slag as an aggregate for use in portland concrete cement.An important aspect of this research was to complete a comprehensive review of other research that has been conducted on the use of steel slag as an aggregate. The literature reviewed included of laboratory studies that focused on the physical, mechanical, chemical, and expansive characteristics of the steel slag. The research on the use of steel slag was gathered from 16 different countries, which include the United States, Spain, Japan, China, Germany, Finland, and Saudi Arabia. Some of these studies have found that properly treated slag may be non-expansive and used in PCC. The possible expansion of the steel slag is the most important characteristic. The expansion of the steel slag aggregate can have detrimental effects on a pavement. This research investigated some of the treatment processes that are being used to alter t

Building pathology and environment: Weathering and decay of stone construction materials subjected to a Csa mediterranean climate laboratory simulation

Building stone materials have to satisfy long-term durability requirements in different environments in terms of mechanical strength and resistance to aggressive conditions. Several studies and field observations show that weathering on geo-materials is related to average annual precipitation and temperature. The decay also depends on salts air/soil concentrations and biological agents, but the more harmful impact is given by greenhouse gas (e.g. CO2, SOX, NOX, O3). These last induce the acidification of the rain and runoff waters. Nowadays, decay prediction is required in order to estimate the behaviour of stone materials over time. This research represents a second part of a previous work where the response to weathering of some construction materials used in ancient and contemporary architecture and cultural heritage has been evaluated by a labo- ratory simulation of hot-summer Csa Mediterranean climate. Simulation consists of accelerate ageing test on climate chamber by reproducing macro (e.g. daily and seasonal cycles of temperature, relative humidity, CO2 air concentration) and micro (e.g. rain, soil capillary rising) environments. Some non-destructive testing were executed to evaluate some physical–mechanical “decay markers” before and after the ageing. Test caused both decreasing and increasing of Leeb D hardness, decreases of permeability and a general decrease of ultrasonic speed, mainly due to the formations of patinas, crusts and efflorescences on the surfaces

Soft Capping of Archaeological Masonry Walls: Far View House, Mesa Verde National Park

The control of moisture and temperature fluctuations within masonry walls is critical for conservation of architectural heritage and especially for fragmentary walls within archaeological sites. Exposed compound walls traditionally have been protected by hard cappings of lime, cement, and modified soil mortars. However, hard capping has been found to be inadequate in addressing the long-term management of moisture ingress and thermal movement that will continue to stress and damage the wall. Instead of protecting the wall as initially designed, hard capping can actually accelerate deterioration over time. In order to counter such problems posed by hard capping, a procedure called \u27soft capping\u27 has been introduced in recent years at several archaeological sites in England, Turkey and elsewhere. Soft capping replaces hard caps with vegetation planted on top of layers of soil, gravel, and geosynthetics. The idea is to prevent water penetration and to reduce thermal fluctuations by taking advantage of plants\u27 abilities to utilize the water and provide a protective barrier on the wall top. The concept is very similar to green roof technology that has gained increased popularity in recent years. This paper will present laboratory and field-based research conducted on the performance characteristics of soft capping for the exposed masonry walls at Mesa Verde National Park, Colorado. Wall movement, moisture and temperature as well as environmental conditions were monitored to evaluate the effects of hard and soft capping on the test walls

Silver Nanoparticles in the Cultural Heritage Conservation

Our cultural heritage is our invaluable social and environmental resource and concern. Moreover, it is a key global economic driver. However, they are subjected to deterioration process and aging. Particularly, microorganisms are nowadays considered harmful agents of biodeterioration of artistic materials due to the fact that their interactions with the material cause not only an esthetical damage due to their visible growth on the surface, but they may affect the interested materials in different ways and at different degrees via mechanical and biochemical processes leading to the formation of pitting, scaling and, in the worst scenario, to the loss of material by its detachment. To protect our shared tangible cultural heritage from biodeterioration and preserve it for future generations, several methods have been developed. Notably, using nanomaterials, with antimicrobial features, has been considered an interesting and economical method to preserve valuable heritage materials. In this chapter, we will present an overview of the decay mechanisms that participate in the deterioration of tangible artworks, in particular microorganisms’ colonization. Next, current works that have been developed to use silver nanoparticles to protect heritage items from microbial colonization and prevent their deterioration have been detailed

Evaluation of the impact of recycled concrete aggregates on the durability of concrete

The building industry has one of the most significant contributions to global warming due to the production of building materials, transportation, building activities and demolition of structures. When the buildings and structures reach the end of their life-span, they are commonly demolished, and debrice is landfield or backfilled if it is evaluated as non-contaminated inert construction and demolition waste (CDW). Implementation of circularity of material and circular economy can significantly reduce pollution and reduce the need for natural resources and opening of new CDW landfills. The use of recycled concrete aggregates (RCA) is one of the possibilities, how to reduce the depletion of raw materials for concrete production. Concrete is the most used building material worldwide, and aggregates constitute 70% of its volume. RCA can replace a certain amount of natural aggregates (NA), and concrete will still perform as required. Aim of this master thesis will be the evaluation of RCA itself, concrete with RCA and its durability performance, particularly freeze-thaw resistance, chloride migration coefficient, resistance to water under pressure and shrinkage. Performance of concrete with two different amounts of RCA will be compared to reference concrete with NA