Solve nonlinear shell equations of Reissner-Naghdi type in the case of 
a cylindrical benchmark problem with membrane-dominated asymptotic behaviour in 
the linear regime. The linearized problem has been described in 
Pitkäranta et al. Shell deformation states and the finite element method: 
a benchmark study of cylindrical shells. Computer Methods in Applied Mechanics 
and Engineering 1995. 128:81-121. As opposed to the reference, here the shell
problem is treated as nonlinear but the shell is subject to a small load 
so that nonlinear effects are not yet significant.

Results below: The error of strain energy when the shell problem is linear
(Large Deflection = False) and when the mesh is refined as

Element Divisions 1 = 1 16 1  
Element Divisions 2 = 1 8 8 1


II. TRIANGLES

Strain reduction method = (solver default)
=============================================
0.17117806858885401
8.0459096871946856E-002
4.0737524719288952E-002
2.1793374374732059E-002
1.2305197940152243E-002


Strain reduction method = 0 (no reduction)
======================================
0.60208880588825542
0.36239878327635855
0.19892547738477828
0.10410455934524342
5.3183057528120692E-002
