This paper discusses the factors that can lead to the degradation of masonry structures and provides an overview of the existing techniques for their rehabilitation and consolidation. The degradation of masonry is often related to negative actions of the environment, such as water penetration, freeze-thaw cycles, chemical attacks, and exposure to pollutants. These factors can lead to the appearance of cracks, scaling, erosion, and other types of deterioration of masonry. To preserve masonry structures, frequent monitoring and repairs (locally), preferably immediately after any degradation, are the most important measures. When degradation occurs, prompt action is necessary to prevent further deterioration and to apply appropriate rehabilitation and consolidation methods. Rehabilitating a construction involves replacing or restoring degraded elements to restore functionality to the pre-degradation level and to improve the overall performance of the structure. In contrast, consolidation focuses on strengthening an existing structure by adding new structural elements or by applying specific consolidation techniques with the aim of achieving increased structural capacity. These processes are often interconnected and part of a larger process of restoring or maintaining buildings or structures. Regarding traditional solutions for consolidating masonry elements and structures, these consist of repairing or rebuilding affected areas with classic materials, such as simple or reinforced mortars, welded meshes, dowels, steel bars and profiles. Traditional masonry repair works include filling cracks by injection, partial disassembly of walls followed by reconstruction, dismantling of mortar joints followed by deep filling, stitching of cracks with steel dowels, and reinforcing and facing with mesh or mortar. These techniques are applied according to the degree and type of degradation of the existing structure, as well as local and environmental conditions, with the aim of ensuring efficient and durable consolidation of the structure. The informed decision on the rehabilitation or consolidation solution used and how it is to be applied is usually made after extensive studies and consultations to achieve the best possible result. Generally, masonry structures are considered very resistant and durable, due to their history of over 6000 years. However, proper care and attention to detail are crucial to prevent degradation and to maintain masonry structures in good condition.
Because of its multiple advantages such as durability, flexibility in use, fire resistance and low production and maintenance costs, concrete is, by far, the most popular building material currently in use. However, cement – one of the base ingredients of concrete – requires large quantities of raw materials and fossil fuels in order to be produced. In fact, in terms of pollution, it is one of the most environment-damaging products of the construction industry. A relatively recent trend in the problem of mitigating cement-related pollution is the possibility to substitute a certain percentage of cement with reactive powders, which are considered to be waste products of other industries. Concurrently, another trend is to try and obtain better performance of plain concrete, by using so-called “disperse reinforcement”. Thus, in the present article, a laboratory study is presented, regarding the obtainment and performance of concrete in which cement has been partially replaced with ultrafine silica and fly ash. Furthermore, in the case of the fly ash recipe, a percentage of metallic fibers was added, in order to study the potential performance gain with respect to plain concrete. The obtained results in compression were encouraging, in the sense that, for all recipes of concrete (plain concrete – used as reference sample versus concrete with fly ash, concrete with ultrafine silica, concrete with fly ash and fibers), the desired concrete strength class was attained. Even more, in the case of obtained results in tension by bending and splitting, the concrete with fly ash and fibers attained almost twice the tensile strength of the plain concrete. The obtained results suggest that concrete with reactive powders and/or metallic fibers can successfully substitute the plain concrete normally used in the construction industry.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.