Use of bacterial binder in repair mortar for micro-crack remediation

2023-04-01
Sırt Çıplak, Elif
Bilecen, Kivanc
Akoglu, Kiraz Goze
Guchan, Neriman Sahin
Micro-cracks are one of the types of stone deterioration which can propagate and lead to surface detachments and larger cracks in the long run. The present study developed a sustainable and environmentally friendly infill material—biological mortar (BM), as an alternative to conventional approaches. Using a biomineralization approach, this BM was explicitly designed for healing micro-cracks (less than 2 mm) in historic travertines. To this end, the mortar was prepared using a calcifyingBacillussp. isolated from thermal spring water resources in Pamukkale Travertines (Denizli), stone powder gathered from travertine quarries in the vicinity, and a triggering solution specifically designed to set off calcium carbon- ate precipitation reaction. After setup, BM was applied to micro-cracks of artificially aged test stones for testing. Scanning electron microscopy revealed calcium carbonate-coatedBacillussp. bodies in the BM matrix, optical microscopy showed secondary calcite minerals throughout the BM applied micro-cracks, and stereomicroscopy and nanoindentation analyses demonstrated bonding of BM with stone due to microbial calcification activities. Furthermore, BM and original material contact showed a continuous and coherent structure in all samples. Within this context, BM could be considered a promising and alternative approach for the remediation of micro-cracks of historic stones.
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
Citation Formats
E. Sırt Çıplak, K. Bilecen, K. G. Akoglu, and N. S. Guchan, “Use of bacterial binder in repair mortar for micro-crack remediation,” APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, vol. 108, pp. 1–15, 2023, Accessed: 00, 2023. [Online]. Available: https://hdl.handle.net/11511/102996.