Historical Heritage Buildings Research Articles

Evaluation of dielectric based and other methods for moisture content measurement in building stones

Preservation and rehabilitation of valuable historic heritage buildings require effective and efficient monitoring systems to ensure proper maintenance of durability and functionality of the building structures and materials. Moisture transport and retention in building infrastructure are some of the most common problems, often inducing structural damage and resulting in harmful microbial growth affecting human health. This work presents an evaluation of measurement techniques for moisture content (MC) in three types of building stone specimens. Moisture measurements, using weight, relative humidity (RH), electrical resistance, capacitance and inductance–capacitance (LC) resonant sensors, were carried out to evaluate moisture measurements in stone. The measurement techniques were evaluated through moisture saturation and drying cycles by partially submerging the stones in water and drying them in air. The results of the MC measurements demonstrate that: (1) RH moisture sensor is not fully capable of measuring the MC in the specimens due to sensor saturation; (2) electrical resistance is nonlinear traversing a large dynamic range from GΩ to kΩ and encounters ion accumulation and polarization problems; and (3) the capacitance and the LC resonant moisture-sensing techniques have a much better signal response to the variation of the moisture content, since both are directly related to the changing dielectric constant in relation to the moisture content. In addition, the LC resonant-sensing technique has an advantage in wireless sensing over other moisture measurement methods. Also, weight measurement results reveal that the moisture behavior in the stone specimens is dominated with capillary transport providing a better understanding of the MC behavior in these three types of building stones. These results lead to the conclusion that the MHz frequency dielectric properties of stone (capacitance) provide better estimates of moisture content than the RH of closed cavities within the stone or DC resistance of the stone.

Analysis of accessibility for buildings of a graduation school – an experiment in ergonomics training curriculum

This article presents a description of a study experience developed in the Discipline of Supervised Internship of the Industrial Design Course of the Federal University of Paraíba. The study is based on focused on ergonomics analysis and accessibility as an object of study, access into and out of buildings of classrooms and laboratories of the same institution. Among the buildings selected, which encompass where the course is established, is a contemporary building and a renovated building of historical and artistic values for current use. The study is characterized by a description of the objects of study, analysis of the reference literature and recommendations for adjustments in the event of any inconsistency with the accessibility standards. The experience of this supervised training provided an opportunity to perform design activities to a group of students in applied ergonomics, as well as enabling contact with professional practice, adding the contact with the appropriate guidelines governing intervention in historic heritage buildings.

Evolution of Damage on Historical Heritage Buildings in Presence of Catastrophic Events and Aggressive Natural Phenomena

A semi-Markov process is defined to model the damage rehabilitation history of buildings in presence of seismic events, natural ageing and rehabilitation strategies. The expected rewards connected to the process are defined; they represent a significant measure of the risk.

Gypsum coatings in ancient buildings

Gypsum plasters from old buildings are a legacy of the building techniques of our ancestors. These coatings, frequently gifted with a high artistic value, are part of the historical building heritage of each country that needs to be well known and preserved. The present paper begins with a general overview of the history of gypsum plasters in Portugal, since the most ancient traces in the Roman period until modern plasters. A description of the main coats that constitute traditional gypsum plasters follows: the lime mortar undercoat, the lime, gypsum and fine sand preparation coat with a thickness of 3–5 mm and the gypsum finishing coat, made of gypsum and air lime slurry. Next, the constitution of the backgrounds is described, namely of the timber framed main walls and of the partition walls typical of the anti-seismic Pombalina construction used in Lisbon after the 1755 earthquake. Finally, the constitutions of the several plaster coats and their production and application process are referred to.

Seismic Stabilization Of Heritage Structures InCalifornia

Historic heritage buildings and monuments are unique structures in California. These structures include bridges and lighthouses, turn of the century factories, churches and hotels, and many of the residential and commercial buildings that form the core of the older cities. Most of California is very seismically active? but few of these heritage buildings have what is currently considered to be an acceptable safety margin against seismic failure. Many structures were demolished but, fortunately, careful consideration is now given to preservation and seismic stabilization of a hlstoric heritage structure before it is subject to demolition or ill-conceived rehabilitation.