Reinforcements

Reinforcements or overhangs of mesh behind the wall, respectively, may considerably increase the wall stability. The basic parameter of reinforcement is the tensile strength R_t. A design value of this parameter is used in all programs (except for the RediRock wall program), i.e. the tensile strength of reinforcement reduced by coefficients taking into account the effect of durability, creep, environment chemistry and installation damage. The force transmitted by reinforcement can never exceed the assigned tensile strength R_t (a default value of 40kN/m is used for gabions).

The second characteristic is the pull-out strength T_p. This parameter determines the anchoring length, i.e. the required length of reinforcement in the soil, for which the reinforcement is fully stressed attaining the value R_t. Since the realistic values of the pull-out strength are difficult to determine, the program offers three options for their calculation, respectively for the calculation of the force F transmitted by the reinforcement.

Length of mesh step joint or reinforcement behind blocks, respectively

Calculate pull-out force

The pull-out force F is given by:

where:	σ	-	normal stress due to self weight at the intersection of mesh and slip surface
	φ	-	angle of internal friction of soil
	C	-	coefficient of interaction (0,8 by default)
	l	-	length of mesh step joint behind the slip surface into the soil body

Computation of the angle υ_a is described in chapter earth wedge.

Input reinforcement anchor length l_k

An anchoring length l_k is specified. This parameter is determined by the shear strength developed between the mesh and the soil gradually increasing from zero to its limit value (measured from the end of reinforcement fixed in soil).

where:	l	-	length of mesh step joint behind the slip surface into the soil body
	lk	-	anchoring length of reinforcement
	Rt	-	tensile strength

Input mesh pull-out resistance T_p

The pull-out force F is given by:

where:	l	-	length of mesh step joint behind the slip surface into the soil body
	Tp	-	pull-out resistance of mesh