SECTION IV BEAMS TABLE REINFORCED CONCRETE BEAMS DEPTH 10" TO LESS THAN 12" 8.8 tons 4 hrs. 2 min. 8.8 tons 1 hr. 53 min. 8.8 tons. 8.

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1 SECTION IV BEAMS TABLE.. REINFORCED CONCRETE BEAMS DEPTH 0" TO LESS THAN B--RC- wide deep reinforced concrete T beam (390 psi); Details: see Note 5 figure. 8.8 tons hrs. 7,, B-0-RC- 0" wide 0" deep reinforced concrete T beam (370 psi); Details: see Note 6 figure. 8.8 tons hr. 53 7, 3 3 / B-0-RC-3 0 / " wide 0 / " deep reinforced concrete T beam (50 psi); Details: see Note 7 figure. 8.8 tons hrs. 0 7, 3 / 3 B--RC- wide deep reinforced concrete T beam (00 psi); Details: see Note 8 figure. 8.8 tons 3 hrs. 3 7, 3, 3 / B--RC-5 wide deep reinforced concrete T beam (50 psi); Details: see Note 9 figure. 8.8 tons 3 hrs. 3 7, 3, 3 B--RC-6 Concrete flange: deep wide (895 psi) concrete; Concrete beam: 7" deep 6 / " wide beam; I beam reinforcement; 0" / " 5 lbs. R.S.J.; cover on flanges; Flange pitch parallel to T ; / " diameter reinforcement: wire mesh No. 3 SWG; Span: ' restrained; Details: see Note 0 figure. B--RC-7 Concrete flange: deep '6 / " wide (355 psi) concrete; Concrete beam: 5" deep 8" wide precast concrete blocks 8 3 / " long; I beam reinforcement; 7" 6 lbs. R.S.J.; cover on bottom; / " cover on top; Flange reinforcement: two rows / " diameter rods parallel to T ; Beam reinforcement: / 8 " wire mesh perpendicular to ; Span: '3" simply supported; Details: see Note figure. B--RC-8 Concrete flange: deep wide (355 psi) concrete; Concrete beam 7" deep / " wide; (scaled from drawing); I beam reinforcement; 0" / " 5 lbs. R.S.J.; no concrete cover on bottom; Flange 6 pitch parallel to T ; / " diameter bars perpendicular to T ; Span: ' restricted. 0 tons 6 hrs. 7, tons hrs. 7, 0 tons hrs. 7,, (Continued) 003 DALLAS EXISTING BUILDING CODE 77

2 TABLE.. REINFORCED CONCRETE BEAMS DEPTH 0" TO LESS THAN (Continued) B--RC-9 / " wide / " deep reinforced concrete T beam (390 psi); Details: see Note figure. 8.8 tons 3 hrs. 7, 3 3 / 3. Load concentrated at mid span.. Achieved hour performance (Class B, British). 3. Failure mode collapse.. Achieved 6 hour performance (Class A, British) / " DIA. BARS 5/ 6 " DIA. STIRRUPS AT 3" 3 /" 5 /" / 3/ " DIA. BARS 5/ 6 " DIA. STIRRUPS AT 3" /" 3 /" 5 /" / " DIA. BARS 5/ 6 " DIA. STIRRUPS AT 3" 3 /" 5 /" 3/ " DIA. BARS 5/ 6 " DIA. STIRRUPS AT 3" 3 /" 5 /" / " DIA. BARS 5/ 6 " DIA. STIRRUPS AT 3" 3 /" 5 /" / / " DIA. BARS 0" / " 5 LB. R.S.J WIRE MESH OF NO. 3 S.W.G 6 /" PITCH (Continued) DALLAS EXISTING BUILDING CODE

3 TABLE.. REINFORCED CONCRETE BEAMS DEPTH 0" TO LESS THAN (Continued).. TILE BOTTOM 6 ' / " BARS AT PITCH / " DIA. RODS 8" STRIP OF HOLLOW TILE FLOOR CONSISTING OF REINFORCED CONCRETE 3 RIBS, / " WIDE WITH HOLLOW CLAY TILES. / 8 " WIRE PLASTER 7" 6 LB. R.S.J. PRECAST CONCRETE BLOCKS. 8 / " LONG SPAN AND END CONDITIONS:-0'-3" (CLEAR). SIMPLY SUPPORTED. / " DIA. BARS 0" /" 5 LB. R.S.J. AT PITCH AT 5 /" 3.. The different performances achieved by B--RC-, B--RC- and B--RC-5 are attributable to differences in concrete aggregate compositions reported in the source document but unreported in this table. This demonstrates the significance of material composition in addition to other details. 3/ 6 " DIA. STIRRUPS AT 3" 3 /" 003 DALLAS EXISTING BUILDING CODE 79

4 TABLE.. REINFORCED CONCRETE BEAMS DEPTH TO LESS THAN B--RC- 8" section; 60 psi aggregate concrete; Reinforcement: - 7 / 8 " rebars at corners; below each surface; / " stirrups 0" o.c. B--RC- Concrete flange: deep wide (305 psi) concrete at 35 days; Concrete beam: 8" deep; I beam reinforcement: 0" / " 5 lbs. R.S.J.; cover on flanges; Flange pitch parallel to T ; / " diameter reinforcement: wire mesh No. 3 SWG; Span: 0' 3" simply supported. 5.5 tons hrs. 7 0 tons hrs. 7, 3, 5 B-3-RC-3 3" Concrete flange: deep wide (385 psi) concrete at 6 days; Concrete beam: 9" deep 8 / " wide; (scaled from drawing); I beam reinforcement: 0" / " 5 lbs. R.S.J.; 3" cover on bottom flange; cover on top flange; Flange pitch parallel to T ; / " diameter reinforcement: wire mesh No. 3 SWG; Span: ' restrained. B--RC- Concrete flange: deep wide (370 psi) concrete at days; Concrete beam: 8" deep 8 / " wide; (scaled from drawing); I beam reinforcement: 0" / " 5 lbs. R.S.J.; cover bottom flange; cover top flange; Flange pitch parallel to T ; / " diameter reinforcement: wire mesh No. 3 SWG; Span: ' restrained. 0 tons 6 hrs. 7, 3, 6, 8, 9 0 tons 6 hrs. 7, 3,, 7, 8, 9. Qualified for hour use. (Grade C, British) Test included hose stream and reload at 8 hours.. Load concentrated at mid span. 3. British test.. British test - qualified for 6 hour use (Grade A ). (Continued) DALLAS EXISTING BUILDING CODE

5 TABLE.. REINFORCED CONCRETE BEAMS DEPTH TO LESS THAN (Continued) / " DIA. BARS WIRE MESH OF NO. 3 S.W.G 6 /" 3 / DIA BARS 8 " DIA. BARS AT PITCH /" AT PITCH 0" /" 5 LB. R.S.J 0" /" WIRE MESH OF 3" 5 LB. R.S.J.. NO. 3 S.W.G 8 / " See Table..3, Note 5. / " DIA. BARS WIRE MESH OF NO. 3 S.W.G 8 /" AT PITCH 0" /" 5 LB. R.S.J. 9. Hourly rating based upon B--RC- above. 003 DALLAS EXISTING BUILDING CODE 8

6 TABLE..3 REINFORCED CONCRETE BEAMS DEPTH TO LESS THAN B-5-RC- 5" Concrete flange: deep wide (390 psi) concrete; Concrete beam: 0" deep 8 / " wide; I beam reinforcement: 0" / " 5 lbs. R.S.J.; cover on bottom flange; cover on top flange; Flange pitch parallel to T ; / " diameter reinforcement: wire mesh No. 3 SWG; Span: ' restrained. B-5-RC- 5" Concrete flange: deep wide (80 psi) concrete; Concrete beam: 0" deep 8 / " wide; I beam reinforcement: 0" / " 5 lbs. R.S.J.; cover over wire mesh on bottom flange; cover on top flange; Flange reinforcement: 3 / 8 " diameter bars at pitch parallel to T ; / " diameter bars perpendicular to T ; Beam reinforcement: wire mesh No. 3 SWG; Span: ' restrained.. Load concentrated at mid span.. Achieved 6 hour fire rating (Grade A, British) tons 6 hrs. 7,, 3 5, 6 0 tons 6 hrs. 7,,, 5, 6 3 BARS DIA. /" BARS AT BARS DIA. BARS AT PITCH PITCH 0" /" 0" /" 5 LB. R.S.J. 5 LB. R.S.J. WIRE MESH WIRE MESH OF NO. 3 OF NO. 3 S.W.G S.W.G 8 /" 8 /" 5. Section 3.7 of the 979 edition of the Uniform Building Code Standards provides: A restrained condition in fire tests, as used in this standard, is one in which expansion at the supports of a load-carrying element resulting from the effects of the fire is resisted by forces external to the element. An unrestrained condition is one in which the load-carrying element is free toexpand and rotate at its support. (R)estraint in buildings is defined as follows: Floor and roof assemblies and individual beams in buildings shall be considered restrained when the surrounding or supporting structure is capable of resisting the thermal expansion throughout the range of anticipated elevated temperatures. Construction not complying... is assumed to be free to rotate and expand and shall be considered as unrestrained. Restraint may be provided by the lateral stiffness of supports for floor and roof assemblies and intermediate beams forming part of the assembly. In order to develop restraint, connections must adequately transfer thermal thrusts to such supports. The rigidity of adjoining panels or structures shall be considered in assessing the capability of a structure to resist therm expansion. Because it is difficult to determine whether an existing building s structural system is capable of providing the required restraint, the lower hourly ratings of a similar but unrestrained assembly have been recommended. 6. Hourly rating based upon Table.., Item B--RC DALLAS EXISTING BUILDING CODE

7 TABLE.. REINFORCED CONCRETE BEAMS UNPROTECTED DEPTH 0" TO LESS THAN B-SU- 0" 0" / " 5 lbs. I beam. 0 tons 39 7 / 3. Concentrated at mid span. TABLE.. STEEL BEAMS CONCRETE PROTECTION DEPTH 0" TO LESS THAN B-SC- 0" 0" 8" rectangle; aggregate concrete (70 psi) with top cover and bottom cover; No. 3 SWG iron wire loosely wrapped at approximately pitch about 7" 6 lbs. I beam. 3.9 tons 3 hrs. 6 7,, / B-SC- 0" 0" 8" rectangle; aggregate concrete (3630 psi) with top cover and bottom cover; No. 3 SWG iron wire loosely wrapped at approximately pitch about 7" 6 lbs. I beam. 5.5 tons 5 hrs. 6 7,, 5, 6, /. Load concentrated at mid span.. Specimen 0-foot 3-inch clear span simply supported. 3. Passed Grade C fire resistance (British) including hose stream and reload.. Specimen -foot clear span - restrained. 5. Passed Grade B fire resistance (British) including hose stream and reload. 6. See Table..3, Note Hourly rating based upon B-SC- above. 003 DALLAS EXISTING BUILDING CODE 83