Parametric Studies on the Behaviour of Reinforced Soil Retaining

Zone-2: This zone is confined between the previously mentioned most critical
surface and the locus of zero required force as shown in Fig.2. 12. A surface beyond
which no additional stresses are required from the reinforcement to maintain
equilibrium is called the locus of zero required force. Ideally, beyond this zone, the
reinforcement can be truncated and equilibrium can be maintained by soil itself, such
length of the reinforcement is called the ideal reinforcement length.
Zone-3: The zone beyond the locus of zero required force is in equilibrium without
requiring any reinforcements.
Jewell (1988) proposed uniform spacing and ideal spacing pattern for reinforcement
spacing. He further explained a truncated length concept and consequences of the
truncation in the design. He also provided several design charts.
Figure 2.12: Reinforcement Layout and Force Distribution for Ideal Length Case (Jewell, 1988)
2. Bonaparte et al. Method (1987) - In this design method, the extensible and
inextensible reinforcements are clearly distinguished. Then, the influence of
reinforcement extensions is evaluated by defining hyperbolic relations
between . Detailed explanation about the method may be referred to Bonaparte
et al. (1987).
3. Tie Back Design Method (1978) - Tie back method was originally developed by
the U.K. Department of Transport (1978) and is based upon limit equilibrium
methods. It is independent of the reinforcement material and it is used with both
inextensible and extensible reinforcement and with anchors.
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