4. B modeling#

4.1. Characteristics of modeling#

The discrete element modeling is the same as in § 3.1. The only difference lies in the way in which the second mode is specified for all analyses on a truncated modal basis: the second mode is specified explicitly by imposing on the nodes \(\mathit{NO2}\), \(\mathit{NO}3\) and \(\mathit{NO}4\) a displacement \(\mathit{DX}\) corresponding to the reference modal deformation of § 2. This is representative of situations where certain modes are the result of experimental reconstruction and specified by imposed displacements.

4.2. Characteristics of the mesh#

Same as § 3.2.

4.3. Tested sizes and results#

The tested quantities, reference values and tolerances are the same as in § 3.3. This makes it possible to ensure that the various static correction methods work in the same way with (i) a fully calculated modal base or (ii) a modal base in which certain modes have been given by imposed displacements.

The results obtained are summarized in the table below:

Values for the relative displacement of node \(\mathrm{NO4}\) at time \(t=\mathrm{19,4}s\) (m):

modal basis

Reference

Tolerance

truncated base

-0.011301

0.1%

full base

-0.011301

1.e -04%

static correction*a posteriori*

-0.011301

0.1%

static correction*a priori*, pseudo-mode, with re-orthogonalization

-0.011301

1.e -04%

static correction*a priori*, static force-imposed modes, with re-orthogonalization

-0.011301

1.e -04%

static correction*a priori*, pseudo-mode, static force-imposed modes, with re-orthogonalization

-0.011301

1.e -04%

Values for the relative displacement of node \(\mathrm{NO2}\) at time \(t=\mathrm{19,4}s\) (m):

modal basis

Reference

Tolerance

truncated base

7.33162E-04

123.0%

full base

7.33162E-04

1.0E -04%

static correction*a posteriori*

7.33162E-04

19.5%

static correction*a priori*, pseudo-mode, with re-orthogonalization

7.33162E-04

1.0E -04%

static correction*a priori*, static force-imposed modes, with re-orthogonalization

7.33162E-04

1.0E -04%

static correction*a priori*, pseudo-mode, static force-imposed modes, with re-orthogonalization

7.33162E-04

1.e -04%