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TRF Serv

The document details the analysis and design calculations for a 26m precast beam for the Bridge Sungai Muda, adhering to the BS 5400-4:1990 design code. It includes information on actual stresses, initial prestress, relaxation losses, permissible stresses, and serviceability limit state stresses at a specific section of the beam. The results indicate the top and bottom stresses, as well as deflection calculations, ensuring the beam meets the required structural performance criteria.

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idah135
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10 views4 pages

TRF Serv

The document details the analysis and design calculations for a 26m precast beam for the Bridge Sungai Muda, adhering to the BS 5400-4:1990 design code. It includes information on actual stresses, initial prestress, relaxation losses, permissible stresses, and serviceability limit state stresses at a specific section of the beam. The results indicate the top and bottom stresses, as well as deflection calculations, ensuring the beam meets the required structural performance criteria.

Uploaded by

idah135
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
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Job: Bridge Sungai Muda Job No.

: 148
Beam: TMbeam- 26m Calc. By: Aqila
Checked:
Data File: \\zar-storage\Eng\2. PROJECTS\31. Paya Keladi\TMBeam26mRev.sam 6/5/2025 2:25:09 PM

Design code: BS 5400-4:1990


Analysis: Stresses at Transfer
Serviceability Limit State
Section Ref 1 at 13m from left end of beam

Section details:
Ref 1 "Section 1"
at 0.5 x span = 13 m from left end of beam
Analysis:
Stresses at Transfer
Serviceability Limit State

—————————————————————————————————————
ACTUAL STRESSES IN PRECAST BEAM
—————————————————————————————————————
No. of tendons fully bonded at this section: 33
No. of tendons fully debonded at this section: 0
No. of tendons deflected at this section: 0

INITIAL PRESTRESS
——————————————————————————————————————————————————————————————
height No of fpu area % of fpu initial force
mm tendons N/mm² mm² kN
——————————————————————————————————————————————————————————————
60.0 17 1860.0 150.0 75.0 3557.25
110.0 14 1860.0 150.0 75.0 2929.5
1040.0 2 1860.0 150.0 75.0 418.5
——————— —————————
TOTAL 33 6905.25

INITIAL RELAXATION
———————————————————————————————————————————————————————————————————
relaxation After relaxation
height No of total trans. loss force moment
mm tendons % % kN kN kN.m
———————————————————————————————————————————————————————————————————
60.0 17 2.5 50.0 44.465625 3512.7844 210.76706
110.0 14 2.5 50.0 36.61875 2892.8812 318.21694
1040.0 2 2.5 50.0 5.23125 413.26875 429.7995
——————— ————————— —————————
TOTAL 33 6818.9344 958.7835

Moment about the centroid of the precast beam:


Mr = 958.7835-(6818.9344*0.55819)
= -2847.51 kN.m
Corresponding stresses:
top stress = 6818.9344/480.412+-2847.51/1.5685E8

SAM v6.60e
Copyright © 2025 Bestech Systems Ltd 6/5/2025 15:29 1
Job: Bridge Sungai Muda Job No.: 148
Beam: TMbeam- 26m Calc. By: Aqila
Checked:
Data File: \\zar-storage\Eng\2. PROJECTS\31. Paya Keladi\TMBeam26mRev.sam 6/5/2025 2:25:09 PM

Design code: BS 5400-4:1990


Analysis: Stresses at Transfer
Serviceability Limit State
Section Ref 1 at 13m from left end of beam

= 14.193915+-18.15409
= -3.9602 N/mm²
bottom stress = 6818.9344/480.412+-2847.51/-1.579E8
= 14.193915+18.037421
= 32.2313 N/mm²

Self weight moment:


c.s.a. = 4.804E5 mm²
density = 25.0 kN/m³
self weight = 4.804E5*25.0
= 12.0103 kN/m
beam length = 26.0 m
distance = 13.0 m
Msw = 0.5*12.0103*13.0*(26.0-13.0)
= 1014.87 kN.m
Corresponding stresses:
top stress = 1014.87/1.5685E8
= 6.47024 N/mm²
bottom stress = 1014.87/-1.579E8
= -6.4287 N/mm²

ELASTIC DEFORMATION LOSSES


stress at top of precast beam = 2.51006 N/mm²
stress at bottom of precast beam = 25.8027 N/mm²
depth of precast beam = 1120.0 mm
——————————————————————————————————————————————————————————————
height No of conc conc tendon tendon
tendons stress strain force moment
mm N/mm² kN kN.m
——————————————————————————————————————————————————————————————
60.0 17 24.55486 6.821E-4 347.86053 20.871632
110.0 14 23.51501 6.532E-4 274.34181 30.177599
1040.0 2 4.173821 1.159E-4 6.9563688 7.2346235
——————— ————————— —————————
TOTAL 33 629.15871 58.283854

Moment about the centroid of the precast beam:


Med = 58.283854-(629.15871*0.55819)
= -292.9092 kN.m

hence top stress = 2.51006-629.15871/480.412--292.9092/1.5685E8


= 2.51006-1.3096219--1.867421
= 3.06786 N/mm²
bottom stress = 25.8027-629.15871/480.412--292.9092/-1.579E8
= 25.8027-1.3096219-1.8554202
= 22.6376 N/mm²

After a further 2 iterations of the above process, the top and bottom
stresses are as follows:
top stress = 3.00296 N/mm²
bottom stress = 22.973 N/mm²

——————————————————————————————————————————
PERMISSIBLE STRESSES IN PRECAST BEAM

SAM v6.60e
Copyright © 2025 Bestech Systems Ltd 6/5/2025 15:29 2
Job: Bridge Sungai Muda Job No.: 148
Beam: TMbeam- 26m Calc. By: Aqila
Checked:
Data File: \\zar-storage\Eng\2. PROJECTS\31. Paya Keladi\TMBeam26mRev.sam 6/5/2025 2:25:09 PM

Design code: BS 5400-4:1990


Analysis: Stresses at Transfer
Serviceability Limit State
Section Ref 1 at 13m from left end of beam

——————————————————————————————————————————
Compression
Clause 6.3.2.2 Table 23
0.5*fci = 0.5 * 60.0
= 30.0 N/mm²
0.4*fcu = 0.4 * 60.0
= 24.0 N/mm²
hence permissible compression stress = 24.0 N/mm²
Tension
Clause 6.3.2.4 (b)(1)
Permissible tension stress = -1.0 N/mm²

——————————————————————————————————————————————————————————————————————
SLS STRESS SUMMARY TABLE
——————————————————————————————————————————————————————————————————————
———————————————————————————————————————————————————————
Concrete Stresses (N/mm²)
force moment In situ Precast
kN kN.m top bottom top bottom
———————————————————————————————————————————————————————

Prestress[1] 6818.93-2847.5 -3.9602 32.2313


Self Weight 1014.87 6.47024 -6.4287
——————————————————————————————————————————————————————
Prestress + Self Weight 2.51006 25.8027

Elastic Def -563.89 261.418 0.49289 -2.8297


——————————————————————————————————————————————————————
TRANSFER 6255.05 -1571.2 3.00296 22.973

————————————————————————————
END ZONE REINFORCEMENT
————————————————————————————
For the design of end zone reinforcement, see the transfer analysis results
for the section at a transmission length from the end of the beam, or at a
debond location.

——————————————————————————————————————————————————————————————————————
SLS FLEXURE
BS 5400:4:1990 Appendix A.2 calculated for uncracked sections
——————————————————————————————————————————————————————————————————————
The deflections are calculated from integration of the curvatures along the
beam, using the parameters detailed below:

Elastic Modulus at Transfer, ET = 36.0 kN/mm²

Precast section height = 1120.0 mm

—————————————————————————————————————————————
Precast Curvature Deflection
Stress E Strain (x10-6 ) (mm)

SAM v6.60e
Copyright © 2025 Bestech Systems Ltd 6/5/2025 15:29 3
Job: Bridge Sungai Muda Job No.: 148
Beam: TMbeam- 26m Calc. By: Aqila
Checked:
Data File: \\zar-storage\Eng\2. PROJECTS\31. Paya Keladi\TMBeam26mRev.sam 6/5/2025 2:25:09 PM

Design code: BS 5400-4:1990


Analysis: Stresses at Transfer
Serviceability Limit State
Section Ref 1 at 13m from left end of beam

(N/mm²) (x10-6 ) (rad/m) Here Max.


—————————————————————————————————————————————

At Transfer T 3.00296 ET 83.4156 -495.29 37.0476 37.0476


B 22.973 638.139

________
[1] includes initial relaxation

End

SAM v6.60e
Copyright © 2025 Bestech Systems Ltd 6/5/2025 15:29 4

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