ABSTRACT To address the significant regional differences in restoration techniques and materials for cultural heritage structures, a series of characterization techniques were conducted on the lime paste from the Cigouying Great Wall in Shanxi Province, China, which provides data support and theoretical basis for the restoration and preservation of Shanxi Great Wall. This study collected lime paste samples from Watchtowers and wall. First, microscopic methods such as X‐ray fluorescence spectrometry (XRF), X‐ray diffraction (XRD), thermogravimetry analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and macroscopic methods such as iodine–starch test and acidification–alkalization test were employed to determine the phases and components of the lime paste. Second, the pore distribution and microscopic morphology of the lime paste were examined by using the mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) to investigate the hardening mechanism of the lime paste in Shanxi Great Wall. The experimental results show that the lime paste from Cigouying Great Wall is dominated by calcium lime and hydraulic components are detected in some lime paste samples. But starch and blood components are not detected. The maximum binder/aggregate mass ratio is 1:0.03, and the minimum is 1:0.36; the aggregate content in the sample is relatively low. Black particles are observed uniformly distributed in some lime paste samples. SEM–energy dispersive spectrometer (SEM–EDS) identified them as carbon substances.
Cao et al. (Tue,) studied this question.