Standard for Fire Safety in Rapid Transit Systems - Singapore Civil ...

APPENDIX C - continued
PART III : PRESTRESSED CONCRETE BEAMS
Description
1. Prestressed concrete beams without any protection shall
comply with SS CP 65 Part 2.
2. As (1) with vermiculite concrete slabs 15mm thick, used as
permanent shuttering:
(a) average concrete cover to tendons
(b) beam width
3. As (2) but with 25mm thick slabs:
(a) average concrete cover to tendons
(b) beam width
4. As (1) with 15mm thick gypsum plaster with light mesh
reinforcement:
(a) average concrete cover to tendons
(b) beam width
5. As (1) with vermiculite/gypsum plaster** 15m thick:
(a) average concrete cover to tendons
(b) beam width
6. As (5) but with 25mm thick coating:
(a) average concrete cover to tendons
(b) beam width
7. Prestressed lightweight concrete without any protection shall
comply with SS CP 65 Part 2.
Minimum dimension of concrete to give a fire
resistance in hours
4 2 1
mm mm mm
- - -
Standard for Fire Safety in Rapid Transit Systems C-5
75*
210
65
180
90*
250
75*
170
50
140
45
125
35
100
50
170
45
125
30
85
- - -
* Supplementary reinforcement, to hold the concrete cover in position, may be necessary.
** Vermiculite/gypsum plaster should have a mix ratio in the range of 1 ½ - 2:1 by volume.
25
70
15
60
30
85
25
60
15
60