The holes caused by dissolution in red-bed soft rock are well developed in Chengdu. Submerging test

leaching test and dissolution test are performed with the samples of red-bed soft rock form different depth of Bandao City in Chengdu. Then the influencing on the environmental water and the erosion degree of soluble components in red bed soft rock containing saline deposit under different processes are analyzed after observing the dissolution characters and behaviors of rock sample under different environmental waters. The results show that the content of gypsum in red-bed soft rock rises with the depth increase. The causticity of rock and environmental water is significantly enhanced; the soluble components of red-bed soft rock dissolve and drain gradually under water

so as to turn to pore enlargement

permeability enhancement

strength reduction and lost of integrity; the acid environmental water makes the calcium carbonate cement drains faster and does great damage to the connection of structure

so as to influence the strength of red-bed soft rock obviously. The compressive strength

wave velocity of the rock are tested after submerging test

leaching test and dissolution test. The test results show that the uniaxial compressive strength of the soft rock reduces obviously after corroded by sulfuric acid. The uniaxial compressive strength reduces for 76% from 8.5 MPa to 2 MPa. The wave velocity in the rock also reduces for 40% from 2 204 m/s to 1 355 m/s. Meanwhile

the pH value of the rock reduces from 8.77 to 7.29 and its conductivity increases from 55 μs/cm to 1 100 μs/cm.