Random Seismic Response and Dynamic Fuzzy Reliability Analysis of Bedding Rock Slopes Based on Pseudoexcitation Method

In the present study, mass movements (landslide and mudslide) bound to a gully located at Mendong, a suburb of Yaounde in Cameroon were examined using hydrological, geotechnical and geomorphological observations. The data indicate that water is an important causative factor of mass movements in the area studied. In fact, the water flow (waste water and runoff) provokes the saturation of materials at the slope foot. These materials lose their mechanical qualities and some deep ruptures generate landslide. During the rainy season, when the cumulative rainfall is more than 200 mm, these landslides are accompanied by mudslides that generate disturbances on the infrastructure situated around the gully and farther downstream. The economic and environmental damages resulting from the Mendong mass movements are considerable, such as degradation of the topography, losses in farm land, transportation and downstream sedimentation in a pond situated at the slope foot, loss of life and damage to the economy. All this calls for a multidisciplinary and integrated approach to hazard assessment and risk mitigation, which included data collection and interpretation, growing public and authority awareness, and preventing or reducing runoff and waste water flows by proper management and drainage.

Hydrological and geotechnical investigations of mass movements in an equatorial city (Yaoundé, Cameroon)

This paper discusses the method of evaluating the shear strength of a rock mass for the Baoquan Pumped Storage Power Station project. Formulae are presented from which numerical characteristics of the shear strength can be derived. The results are compared with those obtained by the centre point of group and least squares methods. The random-fuzzy method is shown to be the more realistic and appropriate approach, allowing for fluctuations of the parameters and corresponding well with the test values.

L. Huaye

Papers

Determination of the shear strength of a rock mass at Baoquan Pumped Storage Power Station