Publication Date:
2019
abstract:
Masonry structures were built by means of various techniques, using materials whose
properties exhibit a considerable scatter depending on the period of construction, regionspecific soil resources and manufacturing procedures. Significant spatial variability within the
structural system is often observed due to diverse deterioration mechanisms. Therefore, it is
important to obtain case-specific information on the mechanical properties of existing masonry
structures.
The case study of a historic building illustrates how the number of destructive tests (DTs)
used to calibrate non-destructive tests (NDTs) can be optimised for the reliability assessment.
Calibrated NDTs are used to establish the probabilistic model for compressive masonry
strength. The specific focus is on compressive strength of masonry units; tests of mortar
strength are only briefly discussed.
The preliminary assessment is based on non-calibrated NDTs. The number of DTs for
calibration is then optimised by means of probabilistic cost optimisation, considering also
possible subsequent actions – ‘do nothing’ or ‘strengthen the structure’. It appears that the
estimates of masonry unit strength based on NDTs are associated with large dispersion and may
be significantly biased. Consequently, it is often beneficial to conduct at least one DT. A
practical tool is provided to determine optimum number of DTs for different outcomes of a
NDT survey and different failure consequences.
properties exhibit a considerable scatter depending on the period of construction, regionspecific soil resources and manufacturing procedures. Significant spatial variability within the
structural system is often observed due to diverse deterioration mechanisms. Therefore, it is
important to obtain case-specific information on the mechanical properties of existing masonry
structures.
The case study of a historic building illustrates how the number of destructive tests (DTs)
used to calibrate non-destructive tests (NDTs) can be optimised for the reliability assessment.
Calibrated NDTs are used to establish the probabilistic model for compressive masonry
strength. The specific focus is on compressive strength of masonry units; tests of mortar
strength are only briefly discussed.
The preliminary assessment is based on non-calibrated NDTs. The number of DTs for
calibration is then optimised by means of probabilistic cost optimisation, considering also
possible subsequent actions – ‘do nothing’ or ‘strengthen the structure’. It appears that the
estimates of masonry unit strength based on NDTs are associated with large dispersion and may
be significantly biased. Consequently, it is often beneficial to conduct at least one DT. A
practical tool is provided to determine optimum number of DTs for different outcomes of a
NDT survey and different failure consequences.
Iris type:
2.1 Contributo in volume (Capitolo o Saggio)
Keywords:
compressive strength, destructive test, historic masonry, masonry unit
characterization, non-destructive test
List of contributors:
Sýkora, M.; Diamantidis, D.; Markova, J.; Masciotta, M. G.
Book title:
Proceedings of the International Conference on Sustainable Materials, Systems and Structures (SMSS2019) - Durability, Monitoring and Repair of Structures