Abstract:

Soft rock is easily disintegrated and softened in the presence of water. Taking the soft rock of a dam foundation in middle Jinsha river as a research object, we selected 8 typical rock samples (argillaceous siltstone) from the dam foundation in the right bank and cut each sample into 3 parts to carry out dry uniaxial compressive test, indoor dry-wet cycle disintegration test, and outdoor natural disintegration test respectively on each part. By recording the initial disintegration time and describing the whole disintegration process, we quantitatively divided the disintegration into three levels completely disintegrated, moderately disintegrated, and not disintegrated. Moreover, we compared the final state of disintegration of the rock samples under dry-wet cycling condition and natural condition. Subsequently, we measured the viscous granule content in the rock samples after wet disintegration. Test results showed that rock samples in dry-wet cycling condition disintegrated more thoroughly than those in natural conditions. The initial time and final state of disintegration are well correlated with the dry uniaxial compressive strength and viscous granule content.

Key words: soft rock , disintegration , compressive strength , viscous granule content