Abstract
The Italian Sacri Monti are heritage sites with some unique characteristics; they are a successful symbiosis between nature and art and are unconfined structures, therefore always being accessible but exposed to atmospheric agents, with many relevant consequences with regard to conservation problems. The paper discusses some aspects related to the application of non-destructive techniques (NDT) for the interpretation of degradation phenomena occurring in stone structural elements. Ultrasonic and impact tests were used to evaluate the structural properties of the stone columns in the Via Crucis portico, within the monumental complex of the Sacro Monte in Ghiffa (Piedmont, Italy), in order to determine their conditions of maintenance and to evaluate the portico static stability. Ultrasonic tests made it possible to obtain the value of the dynamic elastic modulus, which was variable at different points of the columns due to the diversified level of material damage. The impact test, performed with an instrumented hammer in the same points of the ultrasonic test, enables, by comparison, a deeper knowledge of the surface resistance of damaged columns. These results are the first step in a research path that will require further laboratory tests to better calibrate the diagnostic techniques applied to different levels of damage to surface materials.
Highlights
Historical architectural heritage requires specific maintenance and restoration interventions, especially in the presence of prolonged deterioration over time
The diagnostic study studyofofthe thestructural structuralcharacteristics characteristics columns of the Crucis portico mainly based on the of ultrasonic tests, tests, whichwhich were were followed by impact tests at theat same was mainly based onexecution the execution of ultrasonic followed by impact tests the points
While the ultrasonic tests enable the evaluation of the dynamic elastic modulus of the columns same points
Summary
Historical architectural heritage requires specific maintenance and restoration interventions, especially in the presence of prolonged deterioration over time. Ultrasonic tests are one of the non-destructive techniques most often used in the field of diagnostics on historical buildings [14,15,16]. They measure the wave speed through the material thickness, which is in relation to the dynamic elastic modulus. The results obtained by tests on architectural heritage are representative, if compared with known physical characteristics of similar materials, of the degradation inside the structural section of historical elements. The impact tests, performed with an instrumented hammer in the same points of the ultrasonic test, enable the evaluation of the surface degradation level [17]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
