Nonlinear Finite Element Analysis of Concrete Structures

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'ig. 5.2-2: Stress-ctrain curves for the concrete and the liner.
Fig. 5.2-3: Axisymmetric finite element mesh of LM-3
terized by extensive radial cracking initiating at the centre at
a pressure = 3 MPa and extending to the flange when the pressure
is around 8.5 MPa. With increasing pressure these radial cracks
open considerably and circumferential cracks locaced approximately
half-way between the centre and the flange also are initiated.
The maximum pressure obtained was 37.0 MPa where severe
cracking was present. This is illustrated in fig. 4 showing
the upper surface of the LM-1 closure at maximum pressure. This
closure is almost similar to the LM-3 closure. The test terminated
dramatically by ejection of the central part of the closure
A section through the remaining part of the LM-3 closure is
shown in fig. 5