In this paper

the sandstones of the Huangmaqing Group (T2h) were taken as the study object. The compressive and tensile tests were carried out on the rock samples

considering the influencing factors of the slope along the Qinhuai East River in Nanjing city. Since water is the main factor that affects the stability of the excavated slope

both the natural and saturated soaking-drying cycles were taken into account during the experiments. Based on the experimental results of the sandstones

the void and deterioration characteristics and deteriorating mechanism were analyzed in detail. With the increasing number of the soaking-drying cycle

the compressive and tensile strengths

and the cohesion of the sand rock samples all gradually deteriorate. The more the cycle numbers

the more serious damage of the rock mass

which indicates that the cycles have cumulative damage on the samples. Under the natural water absorption conditions (no water entering the small open voids)

the strength and modulus of the rock slowly decrease. However

under the saturated water absorption conditions (the small open voids are filled with water)

the strength and modulus rapidly decrease

which indicates that the deterioration effect due to existence of the small open voids is obvious. The micro-structures indicate that the voids in the rock increase with the number of soaking-drying cycle. Combined with the shear strength characteristics results

the declination of the cohesive strength is the main factor of rock strength deterioration

and the frictional strength almost has no change. The cycles lead to the water-rock reaction

causing gradual loss of rock particle cementation and cracking of the edges

and the rock is degraded in macroscopic scale. Research results have an important reference for the study of stability of new excavation slope

and provide favorable evidences for the long-term stability analysis of river bank slopes.