No-Fines Concrete as Ecologic Stream Bank Erosion Control: Fid-Bau Portal

No-Fines Concrete as Ecologic Stream Bank Erosion Control

Huang, Yuewen / Yu, Xiong (Bill)

No-fines concrete is a pervious concrete obtained by eliminating the sand from normal concrete mix. Compared with conventional concrete, no-fines concrete has unique properties desirable for various applications. Because of the presence of large voids, no-fines concrete has lower density, cost and thermal conductivity, smaller dying shrinkage, no segregation, larger contaminant retaining capability, and reduced capillary movement of water. No-fines concrete is used for construction of pavement, storm water control utilities and green houses. This paper discusses the application of no-fines concrete as an ecology preservative method for stream bank erosion control. Soil erosion is an important factor that can trigger the instability of an embankment. A sustainable revetment should provide soil erosion protection without significantly changing the existing ecologic environment. The strength of no-fines concrete provides sufficient protection against scour of embankments. Although grasses are found to be hard to survive with ordinary types of bank revetment, especially when subjected to periodic inundation from river water level fluctuations, the large pore spaces of no-fines concrete protect grass seeds and provide an environment for grasses to grow. By installing artificial access holes in the no-fines concrete revetment, the ecologic conditions can be preserved to the maximal extent. The design criteria and durability of no-fines concrete revetments are discussed in this paper. This paper also provides an example application of a no-fines concrete revetment that achieved the desirable ecologic effects.