La resistenza di interfaccia calcestruzzo poroso-terreni a grana fina per il consolidamento di pendii mediante trincee drenanti profonde
| Autor: | Ziccarelli Maurizio, Sapienza Giovanni |
|---|---|
| Přispěvatelé: | Ziccarelli Maurizio, Sapienza Giovanni |
| Jazyk: | italština |
| Rok vydání: | 2022 |
| Předmět: |
interface shear strength
Pervious concrete Settore ICAR/07 - Geotecnica used to stabilise slopes must simultaneously satisfy many requirements namely adequate hydraulic conductiv-ity adequate shear strength a few days after pour-ing capacity to act as a protective filter for soils in which the drain is installed good resistance to clog-ging and adequate residual hydraulic conductivity. The pervious concrete with appropriated mix-design can effectively satisfy all the abovementioned requirements. If the trenches depth is such that they intersect the sliding surface and if the trenches are adequate-ly "socket" in the layers of stable soil there is a fur-ther increase in shear strength due to the shear keys effect. This latter is in addition to the increase in shear strength resulting from the reduction of inter-stitial pressures that remains the principal scope of the draining trenches. Obviously the increase of shear strength due to the shear keys effect occurs if the trenches are filled with material that have enough strength and stiffness such as the porous concrete. In this case the beneficial effects of the draining trenches on stability are also due to the resistance at the concrete interface of the trench - soils and to the intrinsic resistance of the concrete at the area of the trench intersected by the sliding surface taken into consideration.The increase in resistance due to the shear keys effect can be very significant in relation to the thickness and interspace of the trenches. Results reported in the paper demonstrated that the interface fine grained soil-pervious concrete is higher than the residual shear strength of the soil |
| Popis: | Le trincee drenanti profonde rappresentano uno dei metodi più efficaci per la mitigazione del rischio da frana, in pendii con falda idrica. Esse sono realizzate mediante pannelli o pali secanti. Il riempimento è costituito di calcestruzzo poroso o materiale granulare. Se le trincee sono adeguatamente “innestate” nel terreno stabile e il materiale di riempimento ha sufficiente resistenza e rigidezza come il calcestruzzo poroso, si ha ulteriore in-cremento di resistenza a taglio per effetto shear keys, oltre a quello derivante dalla riduzione delle pressioni in-terstiziali. L’incremento di resistenza è dovuto sia alla resistenza all’interfaccia calcestruzzo–terreni sia a quella intrinseca del calcestruzzo in corrispondenza della superficie di scivolamento, e può essere molto significativo in relazione allo spessore e all’interasse delle trincee. Nella presente memoria si riportano i risultati di una ricer-ca sperimentale sulla resistenza a taglio di interfaccia calcestruzzo poroso – terreni a grana fina, che dimostra la significatività dell’effetto shear keys. Pervious concrete for deep trench drains, used to stabilise slopes, must simultaneously satisfy many requirements, namely, adequate hydraulic conductiv-ity, adequate shear strength a few days after pour-ing, capacity to act as a protective filter for soils in which the drain is installed, good resistance to clog-ging and adequate residual hydraulic conductivity. The pervious concrete with appropriated mix-design can effectively satisfy all the abovementioned requirements. If the trenches depth is such that they intersect the sliding surface, and if the trenches are adequate-ly "socket" in the layers of stable soil, there is a fur-ther increase in shear strength due to the shear keys effect. This latter is in addition to the increase in shear strength resulting from the reduction of inter-stitial pressures, that remains the principal scope of the draining trenches. Obviously, the increase of shear strength due to the shear keys effect occurs if the trenches are filled with material that have enough strength and stiffness, such as the porous concrete. In this case, the beneficial effects of the draining trenches on stability are also due to the resistance at the concrete interface of the trench - soils and to the intrinsic resistance of the concrete at the area of the trench intersected by the sliding surface taken into consideration.The increase in resistance due to the shear keys effect can be very significant in relation to the thickness and interspace of the trenches. Results reported in the paper demonstrated that the interface fine grained soil-pervious concrete is higher than the residual shear strength of the soil. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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