Guide
FOUNDATION BOLTS
What foundation bolts are, how the types differ, how sizes and coatings are decided, and how project foundation bolt packages are manufactured and supplied by Aashu Bolts in India.
Definition
WHAT A FOUNDATION BOLT DOES
A foundation bolt transfers load from a steel structure into concrete. The embedded portion resists pull-out; the projecting threaded portion clamps the base plate through a nut and washer. Everything about the item — diameter, embedment, projection, bend geometry and thread length — is set by the structural drawing, which is why foundation bolts are ordinarily manufactured to order rather than bought from stock.
On site the consequences of getting this wrong are expensive: a projection a few millimetres short means the nut cannot be fully engaged, and a bolt group set out incorrectly means the column will not land. That is the reason templates, item-wise marking and dimensional checks matter as much as the steel itself.
Types
FOUNDATION BOLT TYPES
The profile is a design decision. These are the four families most often quoted on Indian and export projects.
L Type Foundation Bolt
A single 90-degree bend at the embedded end. The most widely used profile for column bases and general structural anchoring, because the bend develops anchorage within a modest concrete depth.
View product →J Type Foundation Bolt
A hooked embedded end that curls back on itself. Used where the designer wants additional mechanical grip within a shallower or congested foundation block.
View product →Plate Type Anchor Bolt
A plate or heavy washer welded at the embedded end provides bearing area rather than relying on a bend. Common on heavier columns and equipment foundations where pull-out capacity governs.
View product →Straight Anchor Bolt
A straight embedded shank threaded at one or both ends, anchored by a plate, nut or bond rather than a bend. Preferred where the anchorage detail is fabricated rather than formed.
View product →Specification
HOW SIZE, GRADE AND COATING ARE DECIDED
Size and embedment
Diameter and embedded length follow the tension and shear at the base, the concrete depth available and the anchorage type. They are taken from the anchor bolt schedule, not selected from a catalogue.
Material and grade
Carbon steel is the default; higher-strength or corrosion-resistant material is used where the specification calls for it. Aashu Bolts confirms grade against your requirement in writing before production.
Coating and finish
Plain, oiled, zinc plated or hot dip galvanised, chosen for exposure. Galvanising affects thread fit, so nut allowance is agreed as part of the same decision.
Related reading: anchor bolts and how they differ, the manufacturing process and inspection and quality control.
Product range
FOUNDATION BOLTS MANUFACTURED BY AASHU BOLTS
FAQ
FOUNDATION BOLT QUESTIONS
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