Walls of gabion and blocks

The strength test shall be carried out in all the sections corresponding to the steps or to the separation between the gabions, in addition to the intermediate sections at the points of discontinuity. The rectangular near-inflected section is checked and sheared, consisting of non-reactive tensile material or with weak resistance. For gabion walls, the tensile strength of the material is always assumed to be zero.

The reactant section will turn out to be a partialization of the whole, and only in it will be active a certain distribution of internal stresses. In general, if the section is entirely reactive, the diagram of normal voltages will be trapezoidal, possibly interwoven;

If the cross-section is partialized and the material is not a tensile reagent, the diagram of the reacting part shall be triangular with a zero point at the neutral axis; if the cross-section is biased and the material has a certain tensile strength, the diagram shall be a butterfly, with a minimum value equal to the maximum tensile strength and a maximum such that the integral of the pressures balance the stress system.

Internal stability checks

This check is required to verify that the reaction caused by normal stress si and tangential ti inside the structure (the subscript "i" indicates internal) must be below the corresponding limit values silim and tilim, in such a way as to avoid the possibility of recording excessive deformations that can compromise the stability of the work. The values of the efforts silim and t ilim the following can be deduced from empirical formulas:

Where:

When the normal stresses acting at the downstream edge σvi and the upstream edge σmi of the test section are determined by observing that these stresses are caused by stress composed of pressure bending:

where:

The stabilizing moment Mstab and the reversing moment Minstab are evaluated with respect to the valley edge of the work.

The shear stress acting at the verification section turns out to be:

where:

Indicated with σmax and σmin respectively the maximum value and the minimum value between σvi and σmi, the checks in question are passed if the conditions are verified for each limit state

Ed≤Rd

Ed it’s the design value of the action or effect of the action understood as the result of the integration of the effort diagram. Rd is the design value of the resistance of the geotechnical system calculated as a result of compressive limiting stresses.

The shear resistance of the additional bars was determined according to Ec3

Shear design resistance =0.6 * (Tensile strength bar) * (bar area) / 1.25) * Number of bars.