Light-damage assessment

When analysing the effect of earthquakes on masonry buildings, two aspects are important: their safety and their overall functionality. While safety should always be considered first; the functionality of buildings including stuck doors or windows that limit the normal use of the buildings, or small cracks that affect their durability and aesthetics or compromise the feeling of safety offered by the building, are all relevant points to look for. The latter is what concerns the Serviceability (limit state - SLS) or Light Damage of the buildings.

The research into ‘light damage’ focuses on characterising the initiation of cracks in masonry due to earthquakes or other causes, but also the propagation of the cracks, how they widen or lengthen due to new earthquakes. The light damage research looks at the potential causes for existing (light) damage in masonry structures, and at how this affects its performance during future loads.

Laboratory tests with high-resolution cameras track invisible cracks in masonry while they grow and become visible, and detailed models of masonry predict the development of light damage.
Also, an extensive analysis of real masonry houses is conducted to find the causes of the damage and attempt to quantify its attributability to earthquakes.

The following publications present the on-going research into light damage of Dutch masonry:

• Longo, M., Sousamli, M., Korswagen, P., van Staalduinen, P., and Rots, J. G. (2021) Sub-structure-based ‘three-tiered’ finite element approach to soil-masonry-wall interaction for light seismic motion, Engineering Structures. 245, 112847. Retrieved from: https://research.tudelft.nl/en/publications/sub-structure-based-three-tiered-finite-element-approach-to-soil-
• Korswagen, P. A. and Rots, J. G. (2021) Monitoring and quantifying crack-based light damage in masonry walls with digital image correlation. Proceedings of 1st International Conference on Structural Damage Modelling and Assessment - SDMA 2020. Abdel Wahab, M. (ed.). Springer, p. 3-17. (Lecture Notes in Civil Engineering; vol. 110). Retrieved from: https://research.tudelft.nl/en/publications/monitoring-and-quantifying-crack-based-light-damage-in-masonry-wa
• Korswagen, P.A., Longo, M., Rots, J.G. (2020) High-resolution monitoring of the initial development of cracks in experimental masonry shear walls and their reproduction in Finite Element Models. Engineering Structures 211 110365, doi.org/10.1016/j.engstruct.2020.110365. Retrieved from: https://research.tudelft.nl/en/publications/high-resolution-monitoring-of-the-initial-development-of-cracks-i
• Korswagen, P. A., Longo, M., and Rots, J. G., (2020) Calcium silicate against clay brick masonry: an experimental comparison of the in-plane behaviour during light damage. Bulletin of Earthquake Engineering. Retrieved from: https://research.tudelft.nl/en/publications/calcium-silicate-against-clay-brick-masonry-an-experimental-compa
• Korswagen P., Meulman E., Longo M. and Rots J.G. (2019). Crack initiation and propagation in unreinforced masonry specimens subjected to repeated in-plane loading during light damage. Bulletin of Earthquake Engineering. 17(8), p. 4651-4687. Retrieved from: https://research.tudelft.nl/en/publications/crack-initiation-and-propagation-in-unreinforced-masonry-specimen
• Korswagen, P.A., Longo, M., Meulman, E., Rots, J.G. (2019) Experimental and computational study of the influence of pre-damage patterns in unreinforced masonry crack propagation due to induced, repeated earthquakes. 13th North American Masonry Conference, Salt Lake City, Utah, USA, 16-19 June. Retrieved from: https://research.tudelft.nl/en/publications/calcium-silicate-against-clay-brick-masonry-an-experimental-compa
• Terwel, K.C, and Schipper, R. (2018) Innovative Ways of Dealing with Existing Problems: How to reliably Assess the Cause of Damage of Masonry Structures in an Area with Man-induced Earthquakes? IABSE Symposium, Nantes 2018: Tomorrow's Megastructures. International Association for Bridge and Structural Engineering (IABSE), 112. p. S23-39-S23-46. Retrieved from: https://research.tudelft.nl/en/publications/innovative-ways-of-dealing-with-existing-problems-how-to-reliably
• van Staalduinen P.C, Terwel K.C., Rots J.G. (2018) Onderzoek naar de oorzaken van bouwkundige schade in Groningen - Methodologie en case studies ter duiding van de oorzaken. Delft University of Technology. Retrieved from: https://research.tudelft.nl/en/publications/investigation-into-the-causes-of-structural-damage-in-groningen-m