=== Step D: CalculiX-S3 tiebreaker (from disk) ===

CalculiX S3, baseline wind_cc_peak:
  parsed 4639 nodal displacements, 4639 nodal stress tensors
  u_max = 12.7794 mm
  u_p99 = 11.5839 mm
  u_median = 4.5591 mm
  membrane VM_max = 0.4045 MPa  (shell membrane only -- CCX OUTPUT=2D)
  membrane VM_p99 = 0.1425 MPa

Comparison with the other two solvers (baseline wind_cc_peak):
  solver                    u_max [mm]  ratio_to_CCX
  ------------------------------------------------
  CalculiX S3 (S3)              12.779         1.000
  in-house CST+DKT              29.469         2.306
  OpenSees ShellDKGT            52.420         4.102

Interpretation:
  CCX S3 is the trusted reference. Both in-house DKT and
  OpenSees ShellDKGT over-predict deflection vs CCX,
  by 2.31x and 4.10x respectively.
  Both pure-DKT solvers under-stiffen the shell on this curved
  mesh; OpenSees is worse by a further factor of 1.78x relative to in-house.