7/30/2019 Design of Expansion Joint for PSC continuous type superstructure

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Design of Expansion Joint for PSC continuous type superstructure

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LONGITUDINAL MOVEMENT AT END EXPANSION JOINT ON ABUTMENT :

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L = 70.000 m

Ec (M40 gr.) = 1.802 *106

t/m2

( deferred value has b

esh (at 28 days) = 1.90 *10-

ecr(at 28 days) = 4.00 *10-

/(t/m )

fb = 600 t/m2

(assumed)

a = 1.17 *10-5

/oC

T = +/- 25oC

esh*L

ush = fb*ecr*L = 13.3 mm

ucr= = 16.8 mm

------------------------a*T*L 30.1 mm

ut = = +/- 20.5 mm

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+ 50.6 mm

- 20.5 mm------------------------

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Therefore, provide El 40

with a movement of +/- mm with a preset for compression of15 mm.

AT INTERMEDIATE EXPANSION JOINT OVER PIER

The expansion joint gap at this location will twice the expansion gap at the ends.

Therefore, provide M 80

with a movement of +/- mm with a preset for compression of30 mm.

LEGEND:

L = effective length

Ec (M40 GR.) = design value of Modulus of Elasticity for M40 grade =570

ecr (at 7 days) = value of strain due to creep at 7 days

esh (at 7 days) = value of strain due to residual shrinkage at 7 daysecr (at 28 days) = value of strain due to creep at 28 days

esh (at 28 days) = value of strain due to residual shrinkage at 28 days

a = coefficient of expansion per degree centigrade

fb = bottom fibre stress

T = variation in temperature on the basis of extreme climate

ush = longitudinal deck movement due to effect of shrinkage

ut = longitudinal deck movement due to effect of temperature

7/30/2019 Design of Expansion Joint for PSC continuous type superstructure

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ucr = longitudinal deck movement due to effect of temperature

ues = longitudinal deck movement due to effect of elastic short

7/30/2019 Design of Expansion Joint for PSC continuous type superstructure

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en considered )

(fck) N/mm2

7/30/2019 Design of Expansion Joint for PSC continuous type superstructure

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ning