Sedimentary structures and physical properties of travertine and carbonate tufa building stone

摘要

This paper establishes relationships between the structures of travertine and calcium carbonate tufa used as building stones and their physical properties. The most characteristic features of these kinds of rocks are the macropores in both stone types and the bedding planes and laminations in travertines. Large vuggy macropores have little influence on capillary water absorption, strength, elastic modulus or ultrasonic wave propagation, whereas microporosity is a much more determining factor. With travertines, the bedding planes and laminations give petrophysical anisotropy to rocks, where the highest capillary transport is reached parallel to the structure. However, rock strength and elasticity depend on both structure orientation and the predominant rock facies. The strongest and stiffest behaviour is found perpendicular to structure in low-porous banded samples, but in a parallel direction when the rock is highly porous.