@inproceedings{shushakova_fuller_heidelbach_siegesmund_2014, title={Residual strains in structural stone: a degradation mechanism}, DOI={10.1002/9781118889770.ch3}, abstractNote={Since ancient times marble has been used as a decorative and constructional material. Yet, it can be extremely sensitive to weathering and degradation, and hence can have limited durability. Inherent residual strains induced during heating or cooling, and concomitant microcracking, contribute to this degradation. Here we report the influence of stone microstructure on these residual strains via both experiments and microstructure-based finiteelement simulations. Eight marble samples with different composition (calcite and dolomite), grain size, shape preferred orientation, and crystallographic texture are studied. The average grain size varies from 75 μm to 1.75 mm. Four crystallographic texture types (weak, strong, girdle, and high-temperature), observed by electron backscatter diffraction, are used with finite element analysis to compute thermal-elastic responses upon heating. This behavior is compared to measured thermal expansion behavior, which shows increasing residual strains upon repetitive heating-cooling cycles. The thermal expansion behavior can be classified into four categories: isotropic with small residual strain; anisotropic with small residual strain; isotropic with residual strain; and anisotropic with residual strain. Fabric parameters control the extent and directional dependence of the thermal expansion. Good correlation is observed between the experimental and computational results. INTRODUCTION There are numerous cases of degradation of statues, monuments, and facade claddings made of marble (Trewitt and Tuchmann 1 , Ritter 2 , Rabinowitzt and Carr 3 ). Two types of marble degradation are typically observed: a loss of a relief structure and bowing of panels. Such deterioration phenomena depend mainly on climate, particularly on temperature changes. Calcite and dolomite, the two main rock-forming minerals of marble, have large anisotropy in their coefficients of thermal expansion. Calcite has a positive value of 26 x 10 -6 K -1 parallel to the c-axis and negative values of -6 x 10 -6 K -1 parallel to the three aaxes (Kleber 4 ). Dolomite, on the other hand, exhibits positive values parallel to all the crystallographic directions: 26 x 10 -6 K -1 parallel to the c-axis and 6 x 10 -6 K -1 parallel to the a-axes (Reeder and Markgraf 5 ). Thereby, calcite expands parallel to the c-axis and contracts parallel to the a-axes upon heating; and upon cooling the dilation is in the opposite direction (Figure 1). Dolomite expands or contracts in all crystallographic directions upon heating or cooling, but by differing amounts. Such thermal behavior generates stress between adjacent grains and hence governs microcracking. Even small temperature changes can lead to microcrack formation (Battaglia et al. 6 ). Repeated heating and cooling produce grain boundary openings and subsequent closure and as a result govern initiation and propagation of microcracks. Logan et al. 7 pointed out that bowing of marble slabs on the Amoco building in Chicago was produced due to anomalous expansion-contraction behavior of calcite with release of locked stresses. Additionally, experiments (Zeisig et al. 8 , Grelk et al. 9 , Luque et al. 10 ) and the modeling simulations (Weiss et al. 11,12,13 , Saylor et al. 14 , Shushakova et al. 15,16 ) demonstrated that fabric parameters, such as marble composition, bulk texture, Page 1 of 12}, booktitle={Design, Development, and Applications of Structural Ceramics, Composites, and Nanomaterials: Ceramic Transactions, vol 244}, author={Shushakova, V. and Fuller, E. R. and Heidelbach, F. and Siegesmund, S.}, year={2014}, pages={25–37} }