to 0.91).
Figure 3: Polynomial trendline correlation between “Drilling resistance” and “penetrometer measurements” results, including all samples (left) and excluding samples having ratio value “mean resistance to drilling”/“penetrometer resistance” > 10 (right).
Conclusions
In this work, drilling resistance measurement was compared for the first time to mortar penetrometer method, to find a correlation between two micro destructive techniques usable in situ for the evaluation of mechanical resistance of mortars.
Results of tests carried out on ancient mortars belonging to different monuments of different periods and locations proved to be promising.
A good polynomial correlation was showed by drilling and penetrometer data, expecially for low-strenght mortars.
Nevertheless, the study should take considerable advantages from a systematic investigation on a high number of samples having known characteristics. To this aim further work is required to enhance the quality of the collected and compared data, designing specific artificial mortars ad hoc and testing their mechanical data. This kind of data collection could be usefull for the application of the tests in situ in order to have a simple classification of type of mortars.
Another purpose for the future work is to enrich the collected data with compressive strenght and Ultrasonic pulse velocity tests.
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ULTRASONIC TESTING OF THE DOLOMITE MARBLE STATUE OF SOONG CHING-LING WITH RESPECT TO THE DEPTH OF CRACKS AND DETERIORATION STATE
Honglin Ma1, Shibing Dai2, Zhou Yue-e3, Bin Qian4, Zhong Tang2, Gang Zhang1, Jian-kai Xiang1, Gang Zhen1
IN: SIEGESMUND, S. & MIDDENDORF, B. (EDS.): MONUMENT FUTURE: DECAY AND CONSERVATION OF STONE.
– PROCEEDINGS OF THE 14TH INTERNATIONAL CONGRESS ON THE DETERIORATION AND CONSERVATION OF STONE –
VOLUME I AND VOLUME II. MITTELDEUTSCHER VERLAG 2020.
1 Key Scientific Research Base of Conservation on Stone and Brick Materials, National Cultural Heritage Administration (Shaanxi Provincial Institute for the Conservation of Cultural Heritage), No. 35 Kejiyilu, 710075 Xian, China, [email protected]
