What is the minimum grade of concrete specified for these precast elements?

Grade M20 is the minimum grade of concrete to be used (Clause 6.2).

What is the minimum clear cover to reinforcement?

The minimum clear cover to any reinforcement shall be 15 mm (Clause 6.1.2 & Table 3).

What is the main quality control test for finished planks and joists?

The Transverse Load Test (Clause 8), which checks the element's strength and deflection recovery under a specified load.

What are the dimensional tolerances for the length of a plank?

The tolerance on the specified length of a plank is ± 6 mm (Table 1).

IS 13990

: 1994

precast reinforced concrete planks and joists for roofing and flooring

CurrentSpecializedSpecificationBIMStructural Engineering · Planning, Housing and Pre-fabricated Construction

Download PDF BIS Portal Google

This standard specifies the requirements for materials, dimensions, manufacturing, and testing of precast reinforced concrete planks and joists. These components are primarily used for constructing flooring and roofing systems in buildings.

precast reinforced concrete planks and joists for roofing and flooring

Quick Reference Values

Minimum grade of concreteM20

Minimum cover to reinforcement15 mm

Maximum water-cement ratio0.50

Tolerance on length of plank/joist± 6 mm

Tolerance on width of plank± 3 mm

Tolerance on depth of plank/joist± 3 mm

Practical Notes

These are often proprietary systems; always consult the manufacturer's specific design tables and erection guidelines.

Proper handling during lifting and transport is crucial to avoid damage, as these elements are slender.

Pay close attention to seating details on supports and the grouting between units to ensure composite action and load distribution.