IS 2873:1994 is the Indian Standard (BIS) for design of joints in timber structures. This standard provides design criteria, specifications, and detailing guidelines for joints in structural timber. It covers permissible loads, required minimum fastener spacing (edge, end, and pitch distances) for nails, bolts, dowels, and timber connectors to ensure the structural integrity of timber connections.
Provides guidelines for the design and construction of various types of joints in timber structures.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Primary Design Philosophy | Permissible Stress Design (ASD) | Limit State Design (LSD) / Load and Resistance Factor Design (LRFD) | EN 1995-1-1:2004 |
| Minimum bolt spacing (parallel to grain) | 4d (where d is bolt diameter) | (4 + |cos α|)d; For load parallel to grain (α=0), this is 5d | EN 1995-1-1:2004 |
| Minimum end distance for tension member | 7d for softwoods; 5d for hardwoods | 7d for connections loaded in tension parallel to grain | ANSI/AWC NDS-2018 |
| Modification factor for permanent loads | 1.0 (baseline condition) | 0.9 (Load Duration Factor, C_D, for loads >10 years) | ANSI/AWC NDS-2018 |
| Permitted bolt hole oversize | Not exceeding d + 1.5 mm | Not exceeding d + 1.0 mm | EN 1995-1-1:2004 |
| Reduction for bolt group action | Tabulated reduction factors based on number of bolts in a row (e.g., 0.8 for 4 bolts in hardwood). | Calculated using a formula for Group Action Factor (Cg) based on joint geometry, fastener stiffness, and member properties. | ANSI/AWC NDS-2018 |
| Double shear bolt load (parallel to grain) | Twice the value for single shear. | Not necessarily twice the single shear value; calculated independently based on member thicknesses and Johansen yield equations. | EN 1995-1-1:2004 |