The project involved the construction of the Amba Temple, one of the sacred 18 Shakti Peethas, located on exposed hard granite rock with severe surface undulations and an irregular profile. The site lies in a sensitive religious zone, where rock blasting was strictly prohibited by local authorities.
Our firm was appointed for structural consultancy Third party verification.
Site Conditions & Constraints
- Hard, sound granite rock exposed at founding level
- Highly irregular and undulating rock surface
- No permission for blasting due to sensitivity of the site
- Limited scope for conventional excavation and leveling
Adopted Foundation Methodology
After detailed site inspection and engineering assessment, the following solutions were adopted:1. Rock Surface Preparation
Localized manual and mechanical chipping of granite rock to achieve bearing levels wherever feasible.
Design approach guided by IS 12070: 1987 – Code of Practice for Design and Construction of Shallow Foundations on Rock.
2. Direct Reinforcement Anchorage into Rock
Reinforcement bars were drilled and anchored directly into the granite rock using approved chemical anchoring systems.
Adequate embedment length and edge distances were ensured based on:
IS 456: 2000 – Plain and Reinforced Concrete (Clause 26 & Clause 34)
IS 12070: 1987 – Rock anchorage and load transfer principles
3. Execution Challenges
Due to irregular rock geometry, perfect vertical drilling was not always achievable.
Tolerances were managed through controlled drilling, adjusted embedment depth, and site verification.
4. Foundation Blocks with Rock Anchoring
o In areas where direct anchorage was not feasible, RCC foundation blocks were constructed. o These foundations were anchored to the underlying rock mass using reinforcement dowels and chemical anchors to ensure monolithic behaviour
