SEGMENTAL POST-TENSIONED BOX BRIDGE MATERIALS (METRIC)



MATERIALS AND COMPONENT IN USE:

Precast segments  have been manufactured using six main elements

1.Concrete

2.-Prestressing steel

3.-Rebars

4.-Grout

5.-Ducts

6.-Anchorages                                                








CONCRETE:

Typical 28 day concrete strength is  usually set to a minimum value. 

The elastic modulus of concrete can be computed from the equation:   Ec=4800 (f'c)**1/2, where f'c

is the 28 day compressive strength of concrete.  Usually  f'c is not less then 45 MPa



PRESTRESSING   STEEL-STRANDS:
Strand tendons shall consist of low-relaxation steel.Typical material properties are given below:


    NOTE: USE ARMATEK 110 CEMENT TO DO THE GROUT

PRESTRESSING STEEL-BARS:



REBARS:






COVER (PAINT) REBAR WITH "ARMATEC"  FROM SIKA TO PREVENT CORROSION OF THE  REBAR

CEMENT GROUT:













DUCTS:





ANCHORAGES:






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