Details

Autor(en) / Beteiligte

• Sangirardi, Marialuigia
• Judd, Miles R. W.
• Ozdemir, Anil
• Acikgoz, Sinan

Titel

Determining the Young’s Modulus of Lime Mortar Using the Virtual Fields Method

Ist Teil von

• Structural Analysis of Historical Constructions, 2024, p.423-435

Ort / Verlag

Cham: Springer Nature Switzerland

Erscheinungsjahr

2024

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Lime mortars are widely used to repair and retrofit historic masonry structures. There are well-established testing procedures to determine their compressive and tensile strengths. However, there is no consensus amongst practitioners and researchers on the appropriate method to determine their Young’s modulus. In current practice, this parameter is either derived from (i) dynamic response measurements conducted during impulsive excitation and ultrasonic wave transmission tests, or (ii) from limited strain and load measurements obtained during cube and cylinder compression tests. Both strategies have some drawbacks. Dynamic tests operate in the very small strain range and tend to overestimate Young’s modulus. On the other hand, conducting mechanical identification by interpreting limited strain and load measurements using uniform stress and strain assumptions may not yield reliable results. In this paper, we determine the Young’s modulus of lime mortar using an inverse method called the Virtual Fields Method (VFM). This method calculates elastic constitutive parameters directly from full-field surface strains (obtained using Digital Image Correlation) and total load measurements. Different from existing techniques, it enables rigorous consideration of the heterogenous strain fields that arise during testing. To compare methods, identification results obtained for cube shaped natural hydraulic lime samples are compared in this study. The preliminary results demonstrate how VFM provides more appropriate estimates for the Young’s modulus of lime mortar compared to existing methods. Results also highlight factors which contribute to errors in VFM identification results. A brief discussion presents possible methods to further improve identification results.