Question

Question 1 (20 marks) This question refers to the Phase 2 brief. Refer to Section A (see page 4), which is the longitudinal section through the building. A movement joint of some form is to be introduced across the building (perpendicular to Section A) in both upper floors at or near the centre of Scction A. The exact location of and form of the joint may be any of the options you are aware of. For the band beam and slab option for the upper floors, choose a location for the movement joint and show with annotated sketches: (a) where you have chosen to locate the movement joint (b) why you chose that location (c) a suitable joint detail that relates to the band beam, including the reinforcement you expect (d) a suitable joint detail that relates to the slab, including the reinforcement you expect (e) any changes to the bending moments in the band beam What effect does this joint have on the design of the building for lateral load resistance?

Answer 1

Ans a) Movement joint is placed in a location where a beam meets with slab and between slabs and also between two band beams if span of beam is very large ( more than 10 m)

Ans b) The above mention location is chosen to separate the concrete slab from remaining structure so that it can expand and release thermal stresses due to temperature variation.Similarly, movement joint between band beams helps to release thermal stress and avoid cracking.

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Ans e) The majority of bending moment is taken by steel reinforcement so movement joint will not produce much effect on bending moment if placed in region of minimum shear force.

The main reason of providing movement joint is thermal load resistance not lateral load resistance.It will not affect the structure capacity if placed in correct location of place with minimum shear force