STRUCTURAL DESIGN - PART 19

English

31. Deformations of the structure during the construction

The F.E. calculations allowed evaluating the deformations of the structure during the successive phases of the construction.

The values of the horizontal and vertical deflections (in cm) of the arch intradox are listed in the following table.

The values refer to seven different points of the intradox, which are located at L/8, L/4, 3L/8, L/2, 5L/8, 3L/4, 7L/8.

The following deflections during the construction phases were considered:

• deflection of the centering under the dead weight of the arch voussoirs (to be evaluated by the contractor for the centering design)
• deflection of the arch, after the its completion, and under the dead weight of the arch itself (obtained from the model which comprehends arch and abutments, see fig. 17)
• deflection of the structure formed by the arch, the wedges and the spandrels under their dead weights (fig. 18)
• deflection of the whole structure (fig. 19)

The values refer to each construction phase, so that the final deflection is obtained summing all the contributions.

 Construction phases L/8 L/4 3L/8 L/2 5L/8 6L/8 7L/8 Centering TO BE EVALUATED Abutments + arch Vertical -0.01 -0.11 -0.20 -0.22 -0.16 -0.06 +0.02 Horizontal -0.05 -0.01 +0.02 +0.03 +0.03 +0.06 +0.08 Abutments + arch + wedge + spandrels Vertical -0.04 -0.09 -0.12 -0.12 -0.11 -0.08 -0.04 Horizontal +0.00 +0.01 +0.02 +0.00 -0.01 -0.01 +0.00 Bridge Vertical -0.05 -0.11 -0.15 -0.15 -0.14 -0.10 -0.05 Horizontal +0.00 +0.01 +0.02 +0.00 -0.01 -0.01 +0.00

In the paragraph 1.10, we suggested to dismantle the centering only after the completion of all the work phases with the exception of the construction of the paving and of the parapets. The calculations of the deformations have been performed in safety considering that the arch was dismantled just after its completion (to be more precise, when the mortar setting takes place), as a consequence the actual deformations will be not higher than the ones listed in the above table.

Schemes adopted in the calculation of the deformations

fig. 17 - Abutments + Arch

fig. 18 - Abutments + Arch + Wedge + Spandrels

fig. 19 - Bridge

CREDITS:

Intellectual property of this report and of the design drawings is owned by the University of Florence - Department of Civil Engineering

author of the text: Prof.Eng. Andrea Vignoli – other contributes have been mentioned in related paragraphs

© - General Engineering Workgroup -

SOURCE:

Final Design Report