To account for the effects of creep and shrinkage on the composite section, a modified modular ratio, n, is used per EN 1994-1-1:2004 Clause 5.4.2.2(11).

When the conditions of Clause 7.3.1(4) are met the effects of incomplete interaction (i.e., partial composite) is ignored for the calculation of the deflections under the post-composite loads. When the conditions of that clause are not satisfied, no methodology for calculation of deflections is given. The methodology given in Clause 5.2.2(6) of ENV 1994-1-1:1992, which is identical to that given in BS 5950:Part 3:Section 3.1:1990 Clause 6.1.4, is used.

If the option to Apply SCI P405 Rules is selected, the methodology listed there —which is identical to BS 5950: Part 3: Section 3.1: 1990 Clause 6.1.4— is used.