§ 150.093 TABLES OF EARTHQUAKE HAZARD REDUCTION STANDARDS.

   (A)   Rating classifications.

 

Type of Building	Classification
Essential building	I
High-risk building	II
Medium-risk building	III
Low-risk building	IV

 

('65 Code, Table 15-A)

   (B)   Time limits for compliance.

 

Required Action by Owner	Obtain Building Permit Within	Commence Construction Within	Complete Construction Within
Complete structural alterations or building demolition	One year	180 days *	Three years
Wall anchor installation	180 days	270 days	One year
* Measured from date of building permit issuance.

 

('65 Code, Table 15-B)

   (C)   Service priorities and extended time provisions.

Rating Classification	Occupant Load	Extension of Time if Wall Anchors are Installed	Minimum Time Periods for Service of Order
I (highest priority)	Any	One year	0
II	100 or more	One year	90 days
III	100 or more	One year	One year
	More than 50, but less than 100	One year	Two years
	More than 19, but less than 51	One year	Four years
IV (lowest priority)	Less than 20	One year	Four years
Buildings which have obtained a building permit for wall anchors and meet the time schedule in division (B) of this section for wall anchor installation may utilize the time extensions which were permitted in this table prior to the adoption of this chapter.

 

('65 Code, Table 15-C)

   (D)   Horizontal force factors based on rating classification.

 

Rating Classification	IKCS
I	0.186
II	0.133
III and IV	0.100

 

('65 Code, Table 15-D)

   (E)   Horizontal force factors “IS” for parts or portions of structures.

 

Rating Classification	IS
I	1.50
II	1.00
III and IV	0.75

 

('65 Code, Table 15-E)

   (F)   Horizontal force factor “Cp” or portions of buildings or other structures.

 

Part or Portion of Buildings	Direction of Force	Value of Cp
Exterior bearing and non-bearing walls; interior bearing walls and partitions; interior non-bearing walls and partitions over ten feet in height; masonry fences over six feet in height	Normal-to-flat surface	0.20
Cantilever parapet and other cantilever walls, except retaining walls	Normal-to-flat surface	1.00
Exterior and interior ornamentations and appendages	Any direction	1.00
When connected to or a part of a building: Towers, tanks, towers and tanks plus contents, racks over eight feet three inches in height plus contents, chimneys, smokestacks and penthouses	Any direction	0.20

 

When connected to or a part of a building: Rigid and rigidly mounted equipment and machinery not required for continued operation of essential occupancies	Any horizontal direction	0.20
Tanks plus effective contents resting on the ground	Any direction	0.12
Floors and roofs acting as diaphragms	In the plane of the diaphragm	0.12
Prefabricated structural elements, other than walls, with force applied at center of gravity of assembly	Any horizontal direction	0.30
Connections for exterior panels or elements	Any direction	2.00
Notes: (1) See §150.087(B) for use of Cp. (2) When located in the upper portion of any building with a ratio of five to one or greater, the value shall be increased by 50%. (3) For flexible and flexibly mounted equipment and machinery, the appropriate values for Cp shall be determined with consideration given to both the dynamic properties of the equipment and machinery and to the building/structure where placed. (4) The Wp for storage racks shall be the weight of the racks plus contents. The value of Cp for racks over two storage support levels in height shall be 0.16 for the levels below the top two levels. (5) The design of the equipment and machinery and their anchorage is an integral part of the design and specification of such equipment and machinery. The structure to which the equipment or machinery is mounted shall be capable of resisting the anchorage forces (see also §2312 of the Uniform Building Code). (6) Floor and roofs acting as diaphragms shall be designed for a minimum force resulting from a Cp of 0.12 applied to Wp unless a greater force results from the distribution of lateral forces in accordance with §2312 of the Uniform Building Code.

 

('65 Code, Table 15-F)

   (G)   Allowable value of height-thickness ratio of unreinforced masonry walls with minimum quality mortar.1,2

 

	Buildings with Crosswalls as Defined by §150.082	All Other Buildings
Walls of one-story buildings	16	13
First-story wall of multi-story buildings	16	15
Walls in top story of multi-story buildings	14	9
All other walls	16	13
1 Minimum quality mortar shall be determined by laboratory testing in accordance with §150.088(E).
2 This table is not applicable to buildings of Rating Classification I. Walls of buildings within Rating Classification I shall be analyzed in accordance with §150.087(F).

 

('65 Code, Table 15-G)

   (H)   Values for existing materials.

 

New Materials or Configuration of Materials1	Allowable Values
Horizontal Diaphragms
Roofs with straight sheathing and roofing applied directly to the sheathing.	100 lbs. per foot for seismic shear
Roofs with diagonal sheathing and roofing applied directly to the sheathing.	400 lbs. per foot for seismic shear
Floors with straight tongue-and-groove sheathing.	150 lbs. per foot for seismic shear
Floors with straight sheathing and finished wood flooring.	300 lbs. per foot for seismic shear
Floors with diagonal sheathing and finished wood flooring.	450 lbs. per foot for seismic shear

Floors or roofs with straight sheathing and plaster applied to the joist or rafters.2	Add 50 lbs. per foot to the allowable values for items (1) and (2)
Shear Walls
Wood stud walls with lath and plaster.	100 lbs. per foot each side for seismic shear
Plain Concrete Footings	f'c = 150/psi unless otherwise shown by tests
Douglas Fir Wood	Allowable stress same as No. 1 D.F.3
Reinforcing Steel	ft = 18,000 lbs. per square inch maximum3
Structural Steel	ft = 20,000 lbs. per square inch maximum3
1 Material must be sound and in good condition. 2 The wood lath and plaster must be reattached to existing joists or rafters in a manner approved by the Department. 3 Stresses given may be increased for combinations of loads as specified in §150.087(G)(2).

 

('65 Code, Table 15-H)

   (I)   Allowable values of new materials used in conjunction with existing construction.

 

New Materials or Configuration of Materials	Allowable Values
Horizontal Diaphragms
Plywood sheathing applied directly over existing straight sheathing with ends of plywood sheets bearing on joists or rafters and edges of plywood located on center of individual sheathing boards.	Same as specified in Table No. 25-J-1 of the Uniform Building Code (For blocked diaphragms).
Shear Walls
(1) Plywood sheathing applied directly over existing wood studs. No value shall be given to plywood applied over existing plaster or wood sheathing.	Same as values specified in Table No. 25-K-1 (For shear walls).
(2) Drywall or plaster applied directly over existing wood studs.	75% of the values specified in Table No. 47-1 of the Uniform Building Code.

(3) Drywall or plaster applied to plywood sheathing over existing wood studs.	33% of the values specified in Table No. 47-1 of the Uniform Building Code.
Shear Bolts
Shear bolts and shear dowels embedded a minimum of eight inches into unreinforced masonry walls. Bolt centered in a two and one-half inch diameter hole with dry-pack or non-shrink grout around circumference of bolt or dowel.1,3	100% of the values for plain masonry specified in Table No. 24-I of the Uniform Building Code. No values larger than those given for ¼-inch bolts shall be used.
Tension Bolts
Tension bolts and tension dowels extending entirely through unreinforced masonry walls secured with bearing plates on far side of wall with at least 30 square inches of area.2,3	1200 lbs. per bolt or dowel.
Wall Anchors [§150.089(B)(1)]
(1) Bolts extending to the exterior face of the wall with a two and one-half inch round plate under the head. Install as specified for shear bolts. Spaced not closer than 12-inches on centers.1,2,3	600 lbs. per bolt.
(2) Bolts or dowels extending to the exterior face of the wall with a two and one-half-inch round place under the head and drill at an angle of 22½ degrees to the horizontal. Installed as specified for shear bolts.1,2,3	1200 lbs. per bolt or dowel.
Infilled Walls
Reinforced masonry infilled openings in existing unreinforced masonry walls with keys or dowels to match reinforcing.	Same as values specified for unreinforced masonry walls.

Reinforced Masonry
Masonry piers and walls reinforced per §2409 of the Uniform Building Code.	Same as values specified in Chapter 24 of the Uniform Building Code.
Reinforced Concrete
Concrete footings, walls and piers reinforced as specified in Chapter 26 and designed for tributary loads.	Same as values specified in Chapter 26 of the Uniform Building Code.
Existing Foundation Loads
Foundation loads for structures exhibiting no evidence of settlement.	Calculated-existing foundation loads due to maximum dead load plus live load may be increased 25% for dead load, and may be increased 50% for dead load plus seismic load required by the chapter.
1 Bolts and dowels to be tested as specified in §150.088(F).
2 Bolts and dowels to be ½-inch minimum in diameter.
3 Drilling for bolts and dowels shall be done with an electric rotary drill. Impact tools shall not be used for drilling holes or tightening anchor and shear bolt nuts.

 

('65 Code, Table 15-I)

   (J)   Allowable shear stress for tested unreinforced masonry walls.

 

90% of Test Results in psi Not Less Than	Average Test Results of Cores in psi	Seismic In-Plane Shear Based on Gross Area
30 plus axial stress	20	3 psi*
40 plus axial stress	27	4 psi*
50 plus axial stress	33	5 psi*
100 plus axial stress or more	67 or more	10 psi max.*
* Allowable shear stress may be increased by addition of 10% of the axial stress due to the weight of the wall directly above.

('65 Code, Table 15-J)

('65 Code, Table 15-J)