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

Weight of structural secti ons shall be nominal weight
Weight of castings shall be computed from the dimensions shown on the drawings with an
addition of 5 per cent for fillets and over-runs.
Weight of weld fillets ’and the weight of protective coatings shall not be included.
Weight of rivet heads s hall be computed by taking the weight of 100 s nap heads as given in
Table 1900-4.
When specially agreed upon, allowance for snap heads may be taken as a flat percentage of
the total weight. This percentage may be taken as 3 per cent or modified by mutual agreement.
TABLE 1900-4 : WEIGHT OF RIVET HEADS
Dia of Rivet as manufactured mm
Weight of 100 snap heads kg
12 1.3
14 2.1
16 3.4
18 4.45
20 6.1
22 8.1
24 10.5
27 15.0
30 20.5
33 27.2
The Contractor shall supply detailed calculation sheets for the weight of the metal in the
fabricated structure.
No additions s hall be made for the weight of protective coating or weld fillets.
Where computed weight forms the basis for payment, the weight shall be calculated for exact
cut sizes of members used in the structure, deductions being made for all cuts, except for rivet holes .
Additions shall be made for the rivet heads as mentioned above.
When specially agreed upon, the bas is for payment may be the bridge weight complete,
according to specifications included in special provisions of the Contract.
1909. RATE
The contract unit rate for the completed structural steel work shall include the cost of all materials,
labour, tools, plant and equipment required for fabrication, connections, oiling, painting, temporary
erection, inspection, tests and complete final erection as shown on the drawings and as specified in
these Specifications.