Collection and regimentation system for surface and meteoric waters applied directly on the slopes, both soils and rocks and in any pedoclimatic condition.

 

The effects of a soil reinforcement

The effects of a soil reinforcement with Perennial Herbaceous Plants with Deep and Resistant Rooting System (PHPDRRS) block erosion and positively influence the stability of the slope thanks to the properties of water insulation and transpiration. The PHPDRRS it decreases infiltration, cracking and interstitial pressure are reduced, improving the main geomechanical parameters of the soils. This herbaceous plants reinforce the soil ad also protects the traditional surface hydraulic works such as channels and guard ditches, generally made of plastic materials, metal, concrete, and so, on from the silting. It also allows to realize directly on the soil as is as the works action of collection and regimentation of surface and meteoric water, completely avoiding the use of materials and artifacts extraneous to the lithotype of the slope is made such as concrete and iron channels, bridles with stones plastic material and so on.

 

The advantages of this solution

 

 

The advantages of this solution, realized by sowing seeds of PHPDRRS directly on the slopes are:

1. Perfectly adapt to the subsidence of the slope avoiding infiltration,

2. Avoid concentrated weights on the slope,

3. Reduce infiltrations due to breakage and detachment of rigid structures are avoided, even as a result of different thermal expansion and water swellings between the various materials and the underlying lithotype,

4. Highly reduce the speed of the flowing water in the grassed channels,

5. th  kinetic energy of the water, even in the presence of high flow speeds, is dissipated, instant per instant, by friction through the thick epigean coverage,

6. The deep and very tensile resistant roots anchor these herbaceous species, in the underlying lithotype, do not add weigh to the slope, do not create concentrated weights and do not require any maintenances

PHPDRRS change Manning’s number

It has been shown how the choose of PHPDRRS can change Manning’s number by up to 1660% makes the PHPDRRS design of the works and their implementation extremely flexible, as in this full-scale example. It could be observed how, depending on the choice of the PHPDRRS, the flow of water within the grassed channel was slowed down or accelerated according to the herbaceous essences used. As shown in the table below, for traditional materials, Manning’s number is variable in a very small range and does not allow any kind of adaptation due to the situation.

 

 

CONCLUSION

The PHPDRRS Increases in hydraulic flow, with respect to the assumed return times, can be managed and absorbed by the civil work itself; In case of overflow due to exceptional events, all the anti-erosion system act as anti-erosion hydraulic system; Further advantages are the drastic reduction (from 10 to 100 times) the energy consumption and pollution emission of this innovative technology compared to the traditional techniques; The total absence of maintenance;  A positive environmental impact; A drastic reduction of construction times.