What are the main types of joints covered in this code?

Expansion joints, contraction joints (transverse), construction joints, and longitudinal joints (Clause 3).

How deep should a contraction joint be sawn?

The initial saw cut depth should be between one-fourth and one-third of the total slab thickness (Clause 5.4.1).

What is the purpose of a dowel bar in a pavement joint?

To effectively transfer traffic loads across a transverse joint (like an expansion or contraction joint) while permitting axial movement of the slab (Clause 4.3).

What is the typical width of an expansion joint?

The gap for an expansion joint is generally between 20 mm and 25 mm (Clause 4.1).

IS 6509

: 1985

Code of practice for installation of joints in concrete pavements

CurrentFrequently UsedCode of PracticeBIMTransportation · Building Construction Practices incl. Painting, Varnishing

Download PDF BIS Portal Google

This code provides practical guidelines for the construction and installation of various types of joints in concrete pavements, including highways, airfields, and industrial floors. It details the methods for forming, sawing, and sealing expansion, contraction, construction, and longitudinal joints to ensure proper pavement performance and service life.

Code of practice for installation of joints in concrete pavements

Quick Reference Values

Initial saw cut depth for contraction joints1/4 to 1/3 of the slab depth

Typical expansion joint gap width20 mm to 25 mm

Dowel bar diameter for slabs > 20 cm thick25 mm

Recommended dowel bar length500 mm

Typical tie bar spacing for longitudinal joints600 mm to 750 mm

Depth of sealant in a grooveNormally equal to the width, but not greater

Practical Notes

The timing of initial joint sawing is critical. Sawing too early causes ravelling of edges, while sawing too late can result in random, uncontrolled shrinkage cracking.

Ensure dowel bars are perfectly aligned parallel to the slab surface and direction of traffic. Misalignment can lock the joint, preventing movement and causing stress-induced cracking.

Thorough cleaning and drying of the joint groove before applying sealant is essential for achieving a durable, watertight seal. Any debris or moisture will compromise sealant adhesion.