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2.5.2.1 Structural models for overall analysis

Replacement of Application Rule (5) by:

£ (105) Application Rule (5) in 2.5.2.1 of ENV 1992-1-1 does not apply to bridges.

J= 2.5.2.2 Geometrical data

^0 Replacement of Application Rules (2) to (5) by:

(102) For analysis, when a great accuracy is not required, a constant width may be assumed over the whole span.

3 actual flange width may be used.

2.5.2.2.1 Effective width of flanges

(103) For the analysis of the internal forces and moments, the verification at the ultimate limit state, the verification of the limit state of vibration and the calculation of deformations at the serviceability limit state, the

^ (104) For the verification of stresses and crack widths at the serviceability limit state, and the verification of fatigue, the effective width for a symmetrical T-beam may be taken as:

and, for an edge beam (i.e. with flange on one side only)

(for the notations see Figures 2.102 and 2.103 below).

Concrete Beam Effective Width

Figure 2.102: Definitions of dimensions of effective width of flanges

(105) The distance ^ between points of zero moment may be obtained from Figure 2.103 for typical

4 = 24 for cantilever Figure 2.103: Approximate effective spans for calculation of effective width ratios

The following conditions should be satisfied:

i) The length of the cantilever should be less than half the adjacent span.

ii) The ratio of adjacent spans should lie between 1 and 1,5.

(106) For the dispersion of prestressing forces in T-beams see 4.2.3.5.3 in ENV 1992-1-1.

2.5.3 Calculation methods 2.5.3.1 Basic considerations

Replacement of Principle P(4) and Application Rule (5) by:

(104) Global analysis for imposed deformations due to temperature and shrinkage effects should be considered for the serviceability limit state, where relevant.

qq 2.5.3.3 Simplifications

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