IS 13829:1993 Part 1 is the Indian Standard (BIS) for earthquake resistant design and construction of buildings - guidelines: part 1 unreinforced masonry buildings. This Indian Standard provides guidelines for improving the earthquake resistance of both new and existing low-strength stone masonry buildings. It focuses on practical, prescriptive measures such as incorporating horizontal seismic bands, vertical reinforcement, and proper connections between structural elements. The code's primary aim is to enhance the integrity and prevent the collapse of such vulnerable buildings during earthquakes.
Provides guidelines for earthquake-resistant design and construction practices for unreinforced masonry buildings.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Maximum Building Height (Highest Seismicity) | 2 storeys (or 8 m) in Zone V, with 'catching columns'. | Unreinforced masonry is generally not permitted in zones of high seismicity (ag > 0.3g). Height is severely limited for 'simple' or confined masonry. | EN 1998-1:2004 |
| Minimum Wall Thickness (Load-bearing) | 200 mm for 1-2 storey buildings (Table 2). | 240 mm for solid units; thickness also limited by a maximum slenderness ratio (h_ef / t). | EN 1998-1:2004 |
| Minimum Mortar Specification | Not leaner than 1:6 cement-sand mix for walls. | Minimum mortar class M5 (characteristic compressive strength of 5 N/mm²) for unreinforced masonry. | EN 1998-1:2004 |
| Minimum Pier Width | Greater of 600 mm or 0.5 times the clear opening height. | For simple masonry buildings, the horizontal distance between two consecutive openings shall be at least 400 mm. | EN 1998-1:2004 |
| Horizontal Band Longitudinal Reinforcement | Min. 2 bars of 10mm diameter for buildings up to two storeys. | Min. steel area of 300 mm² for tie-beams in medium/high seismicity. (2x10mm bars = 157 mm²). | EN 1998-1:2004 |
| Limit on Openings in a Wall | Total length of openings ≤ 42% of wall length (2-storey, Zone V). | The sum of lengths of openings should not exceed 1/3 of the length of the wall between two tie-beams. | EN 1998-1:2004 |
| Height-to-Length Ratio of Building | Overall length to width ratio not to exceed 3. | Plan aspect ratio (L/B) should not be more than 4. | EN 1998-1:2004 |