Fig. 5: Pore size distribution frequency of samples before and after the salt weathering test.

a Porosity and pore size distribution of sample N-35. b Porosity and pore size distribution of sample S-35. c Porosity and pore size distribution of sample N-25. d Porosity and pore size distribution of sample S-25. e Porosity and pore size distribution of sample N-15. f Porosity and pore size distribution of sample S-15.