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Code Name-1-	International Building Code 2003
Issued by-1-	International Code Council
	The International Building Code 2003 refers to the ASCE 7 document for the determination of horizontal base shear
Revision-1-
Code Name-2-	SEI/ASCE 7-02 Minimum Design Loads for Buildings and Other Structures
Issued by-2-	Structural Engineering Institute of the American Society of Civil Engineers
Revision-2-	2002
Horizontal Base Shear	W: total dead load of structure plus 25% of live load for storage areas; partition load allowance (minimum of 10 psf (0.48 kPa)); permanent equipment loads; and 20% of flat roof snow load if snow load exceeds 30 psf (1.44 kPa). C_S: seismic response coefficient: S_DS: design spectral response acceleration in the short period range (units of g). S_D1: design spectral response acceleration at a period of 1 second (units of g). S_S: mapped maximum considered earthquake spectral response acceleration at short periods (units of g). S₁: mapped maximum considered earthquake spectral response acceleration at period of 1 second (units of g). F_a and F_v: site coefficients (See Table 1). R: response modification factor (See Table 2). I: occupancy factor (See Table 3). T: fundamental period of the structure (seconds): C_u: coefficient for upper limit on calculated period (See Table 4). T_a: approximate fundamental period of structure: h_n: height above the base of the structure to the highest level of the structure. C_t and x: coefficients for period calculation (See Table 5). For structures not exceeding 12 stories in height in which the lateral force resisting system consists entirely of concrete or steel moment resisting frames and the story height does not exceed 10 ft (3 m): N: number of stories Seismic Design Category: taken as the most critical value determined from Table 6. The Seismic Use Group is given in Table 3. The seismic design category is NOT related to the site class (See Table 1)