In the present study early experimental tests concerning local erosion phenomena have been carried out on a particular shape of the already effective circular piers in order to determine if any improvement is verified in their shape coefficient (with a corresponding decrease in scour). In particular, the circular pier foundation has been shaped as a truncated cone, partially or totally sunk into the mobile bed. In the experimental tests a preliminary comparison has been effected between scour at uniform circular pier and non-uniform piers with two different values of bevel angle β for the truncated cone foundation. Experimental results have shown that, for both values of β, the scour depth has been lower than that identified in experimental tests conducted on circular piers of the same diameter but without the truncated cone foundation. This interesting results open up an encouraging research field.

The development of simple methodologies for the management and risk assessment of flood events is a topic of interest for administrators, economists and engineers. In this paper, flood prone areas are identified on the basis of codified return periods of flood events, leading to the identification of appropriate river bands, relative to determining the most appropriate measures in territorial planning and risk mitigation. Hydraulic risk is determined by evaluating the expected damage to vulnerable elements -first and foremost anthropic elements -resulting from the occurrence of an event of known hazard. The risk is determined by means of matrixes that, even if characterized by intrinsic limitations, make it fairly straightforward to estimate a small number of parameters and hence evaluate risk level and attention level in flood phenomena.

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In the present paper, areas under risk of floods are identified on the basis of the codified return periods of flood events, and appropriate river strips are then identified, with reference to which the actions of territorial planning and risk mitigation works can be defined. Hydraulic risk is determined by evaluating the expected damage to vulnerable elements (first and foremost anthropic elements) resulting from the occurrence of an event of known dangerousness. Therefore the level of risk derives from the estimate of phenomenon dangerousness (linked to the identification of the relative river strips with assigned return period) and from the vulnerability of the exposed elements. The risk is determined by means of matrixes that, even if characterized by intrinsic limitations, make it fairly straightforward to estimate a small number of parameters and hence evaluate risk level and attention level in flood phenomena for single hydrographical networks.