Investigating the physico-mechanical characteristics of rocks used in the construction of ancient buildings in Lorestan province with an emphasis on durability (case study: Kashkan Bridge)

Authors

1 Dept., of Geology, Faculty of sciences, Lorestan University, Khoramabad

2 Archaeology Department, Faculty of Literature and Human Sciences, Lorestan University

Abstract

The purpose of this study is to investigate the physical and mechanical properties of limestone used in the construction of the historical bridge of Kashkan (Lorestan province) and to evaluate their behavior against salt weathering. Based on this, two types of limestone used in the construction of Kashkan bridge, including Asmari limestone (ASR) and Talezang (TLZ) were selected and studied in the laboratory. Based on the petrographic analysis results, Asmari stone can be classified as a lime mudstone, while Talezang stone can be classified as a grainstone. In the first stage, the lithological, physical and mechanical characteristics of the studied rocks were determined, and then salt crystallization test was performed in sodium and magnesium sulfate solution in 30 cycles on the selected samples. In order to investigate the effect of salt weathering on the durability and stability of the selected stones, at the end of every 10 cycles, the changes in appearance, P-wave velocity and point load strength of the samples were evaluated. Based on the results, it was found that sodium sulfate has a much greater effect on the decay and degradation of the studied limestones. Also, the results showed that at the end of 30 cycles of salt crystallization test in sodium and magnesium sulfate solution, Asmari limestone has experienced more damage compared to Talezang limestone. In addition to these, SEM studies have been conducted to investigate the structural changes of the samples due to salt weathering.

Keywords



Articles in Press, Accepted Manuscript
Available Online from 31 December 2023
  • Receive Date: 29 November 2023
  • Revise Date: 29 December 2023
  • Accept Date: 31 December 2023