SALIENT FEATURES OF IS:13920 - 1993. CODE OF PRACTICE FOR DUCTILE DETAILING OF RC STRUCTURES SUBJECTED TO SEISMIC FORCES. SHEAR WALL DESIGN : { with / without flange } ( Actual program is available in Super Civil CD )
SR	DESCRIPTION
1	Ductile detailing is a must for structures in Zone IV & V. However it should also be followed in zone III, when  Importance factor is > 1.0  OR  Structure is > 5.0 Storey high  OR  the structure is industrial in nature.
2	Thickness of shear wall should not < 150 MM.
3	Width of Flange (if any) beyond the face of shear wall shall be least of the following: Half the distance to adjacent shear wall web. 1/10 th of total wall height.
4	If factored shear stress > 0.25 * FCK ^ 0.50  OR thickness of wall is > 200 MM, provide steel on both the faces of wall.
5	The Vertical & Horizontal steel in shear wall shall not < 0.25 %. Diameter of bars shall not > 1/10 th of wall thickness.
6	Maximum spacing of bars in horizontal & vertical direction shall be least of the following: Horizontal wall length/5 3 x wall thickness 450 MM.
7	The effective depth for calculation of shear stress shall be taken as 0.80 x wall length.
8	Shear stress shall not exceed maximum permissible limit as per IS:456-2000.
9	While calculating shear capacity of wall, the contribution of concrete & horizontal reinforcements shall be taken in to account.
10	The vertical reinforcements shall not be less than horizontal reinforcements.
11	The cracked flexural strength of wall shall > un-cracked flexural strength.
12	Walls without boundary elements shall have nominal boundary elements as 4 tor 12 mm bars with special confining reinforcements (SCR).
13	When the extreme fiber compressive stress in the wall due to factored  { DL + LL + EL } > 0.20 FCK, boundary elements shall be provided. Boundary elements can be in the form of flanges.
14	Boundary elements shall be designed as short column. The load shall be calculated as = MU-MUV/CW + PROPORTIONAL AXIAL LOAD. MU = APPLIED BM MUV = CAPACITY OF WALL CW = C/C DISTANCE BETWEEN BOUNDARY ELEMENTS/FLANGES.
15	If DL + LL adds to the strength of the wall, its load factor shall be taken as 0.80.
16	The minimum % of steel shall not < 0.8 % & maximum shall not > 4 % in boundary elements.
17	Links in boundary elements shall be as per (SCR) throughout its height.
18	Boundary elements are not required if the entire wall section is provided with (SCR).
19	The coupled shear walls shall be connected by ductile coupling beam.
20	IF the seismic induced shear stress is  > 0.1 * span * FCK ^ 0.50 / D than, entire shear & bending in coupled beam shall be resisted by diagonal bracing. Minimum 4 tor 8 mm shall be provided @ each diagonal brace.
21	Each diagonal of beams shall have (SCR) with link spacing not > 100 MM.
22	Anchorage of diagonals = Ld * 1.5 { in tension }
23	In case of wall openings, the area of vertical & horizontal bars should be such as to equal that of respective interrupted bars. The vertical bars shall extend for full Storey height & horizontal bars shall extend Ld beyond the sides of opening.
24	The vertical reinforcement % ratio across a horizontal construction joint of a shear wall shall not < 0.92/fy x (ss - v/gross area) x 100 ss = shear stress v = factored axial stress, + ve for compression & -ve for tension.
25	Horizontal reinforcement shall be anchored near the edges of the wall OR in (SCR) of boundary elements.
26	Splicing of vertical bars shall be avoided in following regions (greater of :) Wall Length 1/6th of Wall Height. However it should not > 2 * Wall Length.
27	In case the vertical reinforcement is spliced in above region, than not more than 30 % of bars shall be spliced at such locations.
28	Splices in adjacent bars shall be staggered by a minimum of 600 MM.
29	Lateral ties shall be provided around spliced bars having diameter > 16 MM. The diameter of links shall be least of the following. 1/4 of Main Ø 6 MM.
30	Spacing of above links shall not < 150 MM.