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Summary: The need to obtain the mechanical characteristics for analysis and understanding of the mechanical behaviour of historic buildings is highlighted. Destructive tests and non‐destructive tests are widely used for this purpose; however, they only provide a value associated with a specific instant. Structural health monitoring contributes to the monitoring of specific processes before, during, or after an intervention. Nevertheless, among the available sensors, there is a lack of devices for continuous monitoring of stress variations undergone by masonry structures. In response to this need, a new stress‐measurement device for structural monitoring of masonry structures has been developed. It has the aim of determining the initial stress in masonry structural element and providing continuous control of the evolution of the stress variation. The article describes the design of the device, as well as its implementation in a historic building. Moreover, an assessment is performed of the stress variations registered in comparison with the displacements recorded in the monitored areas, as well as the influence of the thermic fluctuations on these. A good relation was confirmed between these measurements. The results demonstrate that the designed device proved to be a useful tool for monitoring structural strengthening interventions. [ABSTRACT FROM AUTHOR]

Summary: In this study, an integrated structural health monitoring system was developed and applied to a masonry heritage building under rehabilitation, where diverse structural changes were made. The late 19th century building had over the years undergone significant deterioration, which brought about the appearance of serious pathological processes affecting the building's stability. In 2012, concerns over the severe cracking phenomena affecting the structure prompted the decision to monitor the structure and to undertake strengthening interventions. A global structural monitoring system was applied to the church to identify the occurrence of possible damage mechanisms and monitoring the intervention processes. The monitoring system was based on the integration of subsystems, which were implemented as and when necessary. Traditional sensors consisting of crackmeters, servo‐inclinometers, cable extension sensors, displacement transducers, wind vanes, and temperature sensors (thermo‐hygrometer and thermocouples) were installed on the building. Moreover, novel measuring approaches using stress sensors and pressure cells were used. Furthermore, manual monitoring elements were installed, which provided measurements for contrasting with those of the continuous sensors, as well as a greater number of monitoring points. Thus, the structural response was measured using 67 monitoring elements. The long‐term (5 years) monitoring results indicated that the interventions were carried out without the occurrence of any irregularity. A good relation was confirmed between the manual and continuous measurements. Moreover, the results have shown the capability of the proposed integrated system to evaluate the structural behaviour during all the phases of the interventions. [ABSTRACT FROM AUTHOR]