Abstract:
At present, an excessive hardening phenomenon is still prevalent in the river regulation works of China. It is urgent to develop ecological revetment technologies for meeting the requirements of ecological protection, sustainable utilization of resources and works safety. The eco-bag retaining wall revetment is the only system which can perfectly integrate the ecological slope with wall works, and the system is a successful way to solve problems of integration of the structural engineering and the ecological engineering. In this paper, taking the bank slope regulation works of the Banqiao River of Nanjing city as a classic case, the design, construction and vegetation planting technologies of the eco-bag retaining wall revetment have been studied in detail. The field test results show that the main factors affecting the engineering quality of the retaining wall revetment of the ecological geo-textile bag are the qualities of the bag, the reinforced material, soil compactness in the bag and vegetation coverage. Taking the ecological geo-textile bag, a typical flexible revetment material, as an example, by comparing the mechanical properties and aging-resistant performance of a new ecological geo-textile bag and an old ecological geo-textile bag used for 1.5 years, the ecological geo-textile bag’s durability is evaluated and studies of the intrinsic relationships between the physico-chemical properties for the ecological geo-textile bag and the engineering quality of the bank slope have been carried out too. The test results show that the retention rate of the mechanical properties is better for the ecological geo-textile bag used for 1.5 years, but it is difficult to meet the requirements of design for 30 years service life. The improved design and construction schemes for the revetment works with the ecological geo-textile bags must be further proposed in order to meet the requirements of mechanics and durability of the revetment works.