Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

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Quality Assurance Handbook for Rural Roads
For use in base course, the Liquid limit and Plasticity Index shall not exceed 45% and 20%
respectively.
(ii) Cement: Cement shall comply with the requirements of IS:269, 455 or 1489
(iii) Lime: (If needed for pretreatment) as per Sub-section 403.
(iv) Water: The water for cement stabilization shall be clean and free from injurious substances.
2. Horizontal Alignment
The edges of the cement stabilized soil layer should be correct within a tolerance limit of (±) 30
mm in plain and rolling terrains and (± )50 mm in hilly terrain.
3. Surface Levels
The tolerance in surface levels for cement treated soil sub-base will be restricted to (+) 10 mm and
(–) 20 mm while for cement-treated soil base, it will be restricted to (±) 10 mm. A grid of 10 m x 2.5
m may be formed to check the surface levels.
4. Surface Regularity
The maximum permitted difference between the cement stabilized soil layer and 3 m straight
edge shall be 12 mm for longitudinal profile and 10 mm for cross profile.
5. Minimum Compressive Strength
For use in base and sub-base courses, minimum 7-day unconfined compressive strength of 2.76
MPa and 1.7 MPa respectively is required.
6. QUALITY CONTROL TESTS
6.1 Tests Prior to Construction
The quality control tests to be carried out prior to construction are indicated in Table 404.2.
Table 404.2 : QUALITY CONTROL TESTS PRIOR TO CONSTRUCTION
Type of Test Frequency
1. Quality of cement and Purity of Lime (IS:1514) One test for each lot
(if used for pre-treatment)
2. Unconfined Compressive Strength Test One test on a set of 3 specimens per km length.
(IS:4332 Part 5)
6.2 Tests During Construction
The quality control tests to be carried out during construction are indicated in Table 404.3.