DIVISION 21 MASONRY

(Division Amended by Ord. No. 181,758, Eff. 8/8/11.)

Section

91.2100   Basic Provisions.

91.2113   Masonry Chimneys.

SEC. 91.2100. BASIC PROVISIONS.

   Chapter 21 of the CBC is adopted by reference with the following exceptions, modifications and additions:

SEC. 91.2113. MASONRY CHIMNEYS.

   (Amended by Ord. No. 182,850, Eff. 1/3/14.)

   Section 2113 of the CBC is adopted by reference, except Section 2113.3 of the CBC is not adopted; and, in lieu, LAMC Subsection 91.2113.3 is added. (Amended by Ord. No. 185,587, Eff. 7/16/18.)

91.2113.3. Seismic Reinforcing. Masonry chimneys shall be constructed, anchored, supported and reinforced as required in this division. In structures assigned to Seismic Design Category C or D, masonry chimneys shall be reinforced and anchored as detailed in CBC Sections 2113.3.1, 2113.3.2 and 2113.4. In structures assigned to Seismic Design Category A or B, reinforcement and seismic anchorage is not required. In structures assigned to Seismic Design Category E or F, masonry chimneys shall be reinforced in accordance with the requirements of CBC Sections 2101 through 2108 and anchored in accordance with CBC Section 2113.4. (Amended by Ord. No. 186,488, Eff. 12/27/19.)

DIVISION 22 STEEL

(Division Amended by Ord. No. 181,758, Eff. 8/8/11.)

Section

91.2200   Basic Provisions.

91.2204   Connections.

SEC. 91.2200. BASIC PROVISIONS.

   (Amended by Ord. No. 185,587, Eff. 7/16/18.)

   Chapter 22 of the CBC is adopted by reference, except that Section 2204.1 of the CBC is modified, and LAMC Subsections 91.2204.1 and 91.2205.3 are added.

SEC. 91.2204. CONNECTIONS.

   (Amended by Ord. No. 182,850, Eff. 1/3/14.)

91.2204.1. Welding.  The details of design, work quality and technique for welding, inspection of welding and qualification of welding operators shall conform to the requirements listed in CBC Sections 2205, 2206, 2207, 2208, 2209, 2210 and 2211. Special inspection of welding shall be provided where required by CBC Section 1705. (Amended by Ord. No. 184,692, Eff. 12/30/16.)

   All welding, except when performed at the shop of an approved fabricator, shall be done by operators certified by the Department for the type of operation involved in accordance with the provisions of CBC Section 1705.2.2.1.

   Complete details of location, type, size and amount of all welds shall be clearly shown on the plans. Where symbols are used on the plans, they shall be the "Standard Welding Symbols," AWS A 2.4, of the American Welding Society (AWS). When it is necessary to use a special erection sequence of welding to minimize locked-up stresses or distortion, the Department may require the erection sequence of welding to be shown on the plans.

   Welding procedures are qualified if they are in accordance with the AWS. Other welding procedures require special qualification approval by the Department. Each application for a special qualification shall be accompanied by a fee of $50.00.

91.2205.3. Modifications to AISC 341, Section F2.5, Members, Special Concentrically Braced Frames (SCBF) Modifications. AISC 341, Section F2.5b. is modified to add a new requirement as follows:

   Section F2.5b(4) - The use of rectangular HSS are not permitted for bracing members, unless filled solid with cement grout having a minimum compressive strength of 3000 psi (20.7 MPa) at 28 days. The effects of composite action in the filled composite brace shall be considered in the sectional properties of the system where it results in the more severe loading condition or detailing.