Slope investigation and safety assessment for Ningbo mountain provincial highway

Safety assessment of highway slopes is important to highway design and construction. For the mountain highways, slope problems are concerned by engineers. In Ningbo area, highway slope disasters frequently occur due to heavy rainfalls and frequent typhoons. In the paper, 7 provincial highways through the mountain area in Ningbo are investigated. Based on the investigated data of 90 slopes, the disaster problems are analyzed. Based on analysis of main influencing factors of the slope safety, multiply factor assessment system is proposed to evaluate slope safety, then, the safety of the investigated 90 slopes is discussed. Through engineering analogue, the established assessment system is certified, and results suggest that assessment conclusions of the established assessment system basically tally with that of other assessment methods, the system is easy to be accepted by engineers because it is simple and can be operated conveniently.