Vid i fyd [cos li sin s lw

5.5.3.4.5 Detailing for local ductility

(1)

Paragraph 5.4.3.4.2(1) applies.

(2)

Paragraph 5.4.3.4.2(2) applies.

(3)

Paragraph 5.4.3.4.2(3) applies.

(4)

Paragraph 5.4.3.4.2(4) applies.

(5)

Paragraph 5.4.3.4.2(5) applies.

(6)

Paragraph 5.4.3.4.2(6) applies.

(7)

Paragraph 5.4.3.4.2(8) applies.

(8)

Paragraph 5.4.3.4.2(10) applies.

(9) If the wall is connected to a flange with thickness bf > hs/15 and width lf > hs/5 (where hs denotes the clear storey height), and the confined boundary element needs to extend beyond the flange into the web for an additional length of up to 3bwo, then the thickness bw of the boundary element in the web should only follow the provisions in 5.4.1.2.3(1) for bwo (Figure 5.11).

Figure 5.11: Minimum thickness of confined boundary elements in DCH walls with large flanges

Figure 5.11: Minimum thickness of confined boundary elements in DCH walls with large flanges

(10) Within the boundary elements of walls the requirements specified in 5.5.3.2.2(12) apply and there should be a minimum value of ®wd of 0,12. Overlapping hoops should be used, so that every other longitudinal bar is engaged by a hoop or cross-tie.

(11) Above the critical region boundary elements should be provided for one more storey, with at least half the confining reinforcement required in the critical region.

(13)P Premature web shear cracking of walls shall be prevented, by providing a minimum amount of web reinforcement: ph,min = Pv,min = 0,002.

(14) The web reinforcement should be provided in the form of two grids (curtains) of bars with the same bond characteristics, one at each face of the wall. The grids should be connected through cross-ties spaced at about 500 mm.

(15) Web reinforcement should have a diameter of not less than 8 mm, but not greater than one-eighth of the width bwo of the web. It should be spaced at not more than 250 mm or 25 times the bar diameter, whichever is smaller.

(16) To counterbalance the unfavourable effects of cracking along cold joints and the associated uncertainties, a minimum amount of fully anchored reinforcement should be provided across such joints. The minimum ratio of this reinforcement, pmin, necessary to re-establish the resistance of uncracked concrete against shear, is:

0,0025

where Aw is the total horizontal cross-sectional area of the wall and NEd shall be positive when compressive.

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