Design Considerations for Fire Resistance - Simplified Design of Reinforced Concrete Buildings - page 272

Table 10-5 Construction Classification, Restrained and Unrestrained
(Table X3.1 from ASTM E 119)

I. Wall bearing

Single span and simply supported end spans of multiple bays: A

(1) Open-web steel joists or steel beams, supporting concrete slab, precast units, or metal decking unrestrained

(2) Concrete slabs, precast units, or metal decking unrestrained

Interior spans of multiple bays:

(1) Open-web steel joists, steel beams or metal decking, supporting continuous concrete slab restrained

(2) Open-web steel joists or steel beams, supporting precast units or metal decking unrestrained

(3) Cast-in-place concrete slab systems restrained

(4) Precast concrete where the potential thermal expansion is resisted by adjacent construction B restrained

II. Steel framing:

(1) Steel beams welded, riveted, or bolted to the framing members restrained

(2) All types of cast-in-place floor and roof systems (such as beam-and-slabs, flat slabs, pan joists, restrained

and waffle slabs)where the floor or roof system is secured to the framing members

(3) All types of prefabricated floor or roof systems where the structural members are secured to restrained

the framing members and the potential thermal expansion of the floor or roof system is resisted

by the framing system or the adjoining floor or roof construction B

III. Concrete framing:

(1) Beams securely fastened to the framing members restrained

(2) All types of cast-in-place floor or roof systems (such as beam-and-slabs, pan joists, and waffle restrained

slabs) where the floor system is cast with the framing members

(3) Interior and exterior spans of precast systems with cast-in-place joints resulting in restraint restrained

equivalent to that which would exist in condition III (1)

(4) All types of prefabricated floor or roof systems where the structural members are secured to restrained

such systems and the potential thermal expansion of the floor or roof systems is resisted by the

framing system or the adjoining floor or roof construction B

IV. Wood construction:

All Types unrestrained

A Floor and roof systems can be considered restrained when they are tied into walls with or without tie beams, the walls
being designed and detailed to resist thermal thrust from the floor or roof system.
B For example, resistance to potential thermal expansion is considered to be achieved when:
(1) Continuous structural concrete topping is used,
(2) The space between the ends of precast units or between the ends of units and the vertical face of supports is filled
with concrete or mortar, or
(3) The space between the ends of precast units and the vertical faces of supports, or between the ends of solid or
hollow core slab units does not exceed 0.25% of the length for normal weight concrete members or 0.1% of the
length for structural lightweight concrete members.
*Copyright ASTM. Reprinted with permission.

Table 10-6 Minimum Cover for Reinforced Concrete Columns, in.