Specification Part 3 - Road & Bridge Works - Urban Administration ...

505.7. Measurement for Payment
Penetration Macadam base course shall be measured as finished work in square meters.
505.8. Rate
The contract unit rate for Penetration Macadam course shall be payment in full for carrying out
the required operations including, but not necessarily limited to, all components listed in Clause
501.8.8.2 (i) to (xi).
506. BUILT-UP SPRAY GROUT
506.1. General
Built up spray grout shall be consist of a two-layer composite construction compacted crushed
coarse aggregates with application of bituminous binder after each layer, for binding, finishing
with key aggregates at the top of the second layer, so as to yield total thickness not exceeding 75
mm. Built up spray grout serve as a base course and shall be in conformity with the line grades
and cross sections shown on the approved drawing or as directed by the Engineer in charge.
Built up spray grout shall be used in a single course in a pavement structure.
506.2, Materials
506.2.1. Bitumen: Clause 504.2.1. Shall apply. Where permitted by the Engineer in charge, an
appropriate grade of emulsion complying with IS 8887 may be used.
506.2.2. Aggregates: The coarse aggregate shall conform to Clause504.2.2. The aggregate
shall satisfy the physical requirements set out in Table 500-3. The coarse and key aggregates for
built-up spray grout shall conform to the grading given in Table 500-7.
TABLE 500-7
Grading Requirements for Coarse and Key Aggregates for Built-up Spray Grout
IS Sieve
Cumulative per cent by weight of total aggregate passing
Designation (mm) Coarse Aggregate
Key Aggregate
53.0 100 -
26.5 40 - 75 -
22.4 - 100
13.2 0 - 20 40 - 75
5.6 - 0 - 20
2.8 0 - 5 0 - 5
506.3. Construction Operations
506.3.1. Weather and seasonal limitations: The provisions of Clause 501.5.1 shall apply.
506.3.2. Equipment: The provisions of Clause 505.3.2 shall apply.
506.3.3. Preparation of base: The base on which the built-up spray grout course is to be laid
shall be prepared, shaped and compacted to the specified lines, grades and cross -sections in
accordance with Clauses 501 and 902 as appropriate. A prime coat shall be applied in
accordance with Clause 502 with approved primer as directed by the Engineer in charge.
506.3.4. Tack coat: A tack coat shall be applied in accordance with the procedure described in
Clause 503, as directed by the Engineer in charge.
506.3.5. Spreading and rolling coarse aggregates and application of binder for the first
layer:
(i)Immediately after the application of prime or tack coat, the clean, dry and dust free coarse
aggregates shall be spread uniformly and evenly, by mechanical means, at the rate of 0.5 cu. m.
per 10 sq. m. area.
(ii)Immediately after spreading of the aggregates, the entire surface shall be rolled with an 8 - 10
tonnes smooth wheel steel roller. Rolling shall commence at the edges and progress towards the