Concrete Joint filler is a material used between two sections of concrete.
It is relatively a compressed material so that it does not fail as the concrete grows around it and shrinks due to temperature change or movement.
The joint filler prevents untimely failure of the concrete structure.
Types of Concrete Joint filler:
Following are the few types of joint filler materials as follows:
Softwood means wood that has been cut from coniferous or evergreen trees, it is usually used as construction materials.
Softwoods come from evergreen and coniferous trees, similar to pine, cedar or spruce.
Bitumen impregnated fibre board is an enlargement joint fillers in sheet types, used to form and fill expansion joints in-situ and precast concrete.
Cork bound with bitumen:
It is a pure cork-based expansion joint filler board that expands and compresses inside the concrete joints to supply permanent safety.
Properties of Concrete Joint filler:
In order to satisfy the properties of materials to be used as satisfactory filler materials, based on IRC recommendations are:
The pressure required to compress the specimen to 50 per cent of its original thickness should be between 7 to 53 kg/ cm2.
Materials should not show loss of its original weight by more than 3 per cent.
The specimen should recover at least 70 per cent of the original thickness after the load is applied and released after one hour at the end of the third application of load.
The extrusion of one edge should not be more than 6.5 mm when the specimen is compressed to 50 per cent of its thickness with three edges restrained.
Uses of Concrete Joint filler:
- Joint filling is an important process in many structures such as buildings, masonry walls.
- The layers of material are combined to form a strip of compressed and non-compressed layers and to be combined in an uncompressed position compared to a single joint.
- A composite filler is used in the joints between structural elements comprised of one layer of a substantially non-compressed, moisture inhibiting material.
The combined filler serves the purpose of the space occupation, so that there is no void space left for their accommodation.