Page 468 - Forensic Structural Engineering Handbook

13.14 MATERIAL-SPECIFIC FORENSIC ANALYSES

TABLE 13.8 Required Minimum Equivalent Thickness for Fire Resistance of Clay Masonry
Walls, in (mm)
Material type 1 h 2 h 3 h 4 h

Solid clay or shale brick 2.7 (69) 3.8 (97) 4.9 (124) 6.0 (152)
Hollow brick or structural 2.3 (58) 3.4 (86) 4.3 (109) 5.0 (127)
clay tile or clay or shale
Hollow brick or structural 3.0 (76) 4.4 (112) 5.5 (140) 6.6 (168)
clay tile of clay or shale solidly
grouted or aggregate-filled§

*Determine fire resistance ratings between those listed by linear interpolation.
†For units in which the net cross-sectional area of cored brick in any plane parallel to the surface contain-
ing the cores should be at least 75 percent of the gross cross-sectional area measured in the same plane.
‡Where combustible members are framed into the wall, the thickness of solid material between the ends of
each member and the opposite face of the wall, or between members in from opposite sides, shall be not less
3
than 95% of the thickness shown less 8 in.
§Sand, pea gravel, crushed stone, or slag (ASTM C 33, Specification for Concrete Aggregates); pumice,
scoria, expanded shale, expanded clay, expanded slate, expanded slag, expanded fly ash, or cinders (ASTM C
331, Specifications for Lightweight Aggregates for Concrete Masonry Units); ASTM C 549, Specification for
Perlite Loose Fill Insulation; or ASTM C 516, Specification for Vermiculite Loose Fill Thermal Insulation. 62

TABLE 13.9 Minimum Equivalent Thickness Required by ASTM C 652-92 for Clay or Shale
Hollow Brick
Equivalent thickness, in (mm)
Nominal thickness, Specified thickness, Filled 100% Class H60V Class H40V
in (mm) in (mm) solid 40% solid 60% solid
4 (100) 3.5 (90) 3.5 (90) 1.40 (36) 2.10 (53)
6 (150) 5.5 (140) 5.5 (140) 2.20 (56) 3.30 (84)
8 (200) 7.5 (190) 7.5 (190) 3.00 (76) 4.50 (114)
10 (250) 9.5 (240) 9.5 (240) 3.80 (97) 5.70 (145)
12 (300) 11.5 (290) 11.5 (290) 4.60 (117) 6.90 (175)

TABLE 13.10 Minimum Equivalent Thickness Provided by ASTM C 216, C 62, C 55,
and C 73 for Brick
Nominal Specified Equivalent Equivalent
thickness, thickness, thickness, 75% thickness, 100%
in (mm) in (mm) solid, in (mm) solid, in (mm)

3 (75) 3 (75) 2.35 (60) 3 (75)
4 (100) 3.5 (89) 2.63 (67) 3.5 (89)
4 (100) 3.63 (90) 2.72 (69) 3.63 (90)
6 (150) 5.5 (140) 4.13 (105) 5.5 (140)
6 (150) 5.63 (140) 4.22 (107) 5.63 (140)