An analytical study of the tabia mortar from Lin Yimu’s tomb, Zhejiang, China

Abstract

The Lin Yimu’s tomb in Zhejiang Province, China, is a significant Qing Dynasty tabia structure that, despite relatively good preservation, has suffered damage from weathering, necessitating urgent restoration. In this study, we conducted a comprehensive scientific analysis of archaeological samples from the tabia of Lin Yimu’s tomb, employing a range of analytical techniques including X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX), Fourier transform infrared spectroscopy (FTIR), chemical methods, and measurements of hardness and strength. Analytical results revealed that the main phases of the sample are calcite, quartz, illite/mica, feldspar, with a minor presence of Tung oil. The proportion of calcium carbonate is approximately 27%, and the ratio of earth to sand is 1:2, suggesting a raw material formula mass ratio of lime-earth-sand of 3:4:8. The surface hardness of the sample is measured at 293 ± 15 HL, with a compressive strength of 5.5 ± 0.2 MPa. The sand used in the raw material has a medium particle size of 250 μm, while earth particles are predominantly around 17 μm. The sample exhibits a porosity of 27.5%, with pore sizes concentrated at 95 nm. These findings contribute significantly to our understanding of Qing dynasty tomb construction technologies and provide a solid scientific basis for the restoration of such historical sites.