Penetration of concrete into gravel filter beds

Conclusions

• 1. In addition to ordinary losses in pouring concrete for slope protection, extra quantities are used (as much as 9.4% of the design volume) due to penetration into the filter and settlement of the filter.

• 2. Extra quantities are also used (about 3% of the design quantities) due to inaccurate grading and shaping of the surfaces of gravel bed and concrete slab.

• 3. Increase in thickness of the concrete slab should be allowed for in the design by reducing the design thickness.

• 4. In the documentation of a project and in the agreements relating to it, the requirements of quantities and final dieensions should be more fully developed and stated.