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  1. Jean_Wong

    Moment discrepancy on bridge columns for piers with same span

    After trying to replicate the problem, I have found out that the huge differences in moments originate from the curve. I made 3 similar models with different offsets from the longitudinal axis. With regards to straight model, the difference between column moments are not too high, especially...
  2. Jean_Wong

    Moment discrepancy on bridge columns for piers with same span

    The image above (Piers P142, P143, P144, P145 respectively) shows the deflection for transverse earthquake. Longitudinal direction is along the bridge while transverse direction is perpendicular to that direction. Both are on the horizontal plane. STAAD FILE Link
  3. Jean_Wong

    Moment discrepancy on bridge columns for piers with same span

    Good Day! I am designing a 13-span curved bridge for railway, part of which is shown in the image uploaded. The members between piers in the image are the girders. Piers P142 and before support a pocket track which is why there are 3 girders. P143 onwards only support 2 girders. These are...
  4. Jean_Wong

    Barrier design & dimensions for railway

    DLBridge: Thanks for pointing to the commentary! SlideRuleEra: It's hard to find code for light rail transits so we used AREMA and AASHTO LRFD for the designs. Anyways, The height of the collision load is 1.2m high, I might increase the height of the barrier to 1.6m. For the thickness, at...
  5. Jean_Wong

    Barrier design & dimensions for railway

    SlideRuleEra: the barriers are used to prevent trains going to the highway on either side of the track. dhengr: My first question was about the thickness to consider when designing a single slope barrier? Is the average thickness ok? With regards to the load, I will just request information...
  6. Jean_Wong

    Barrier design & dimensions for railway

    Good day! In our railway project, there are concrete barriers at both guide-way edges. The formula I used is the one on AASHTO LRFD 2012 Page 13-19 If the barrier is sloping (150mm at top, 200mm at bottom, 1200mm in height), what is the thickness that should be considered when calculating for...
  7. Jean_Wong

    Preventing settlement from MSE Wall?

    Thank you for all the answers! Realignment is good considering maintenance issues but can be costly since right of way extension might be needed. I would consider lightweight fill if it can resist collision and seismic forces. For the meantime, is there a good reference or sample...
  8. Jean_Wong

    Preventing settlement from MSE Wall?

    The pipe runs along/parallel to the embankment. The embankment height increases from 3.5m to 8.0m at a distance of around 190m. The pipe curves at some point so it doesn't run along all 190m, but still a significant distance. I would consult with client and the local government if the pipe could...
  9. Jean_Wong

    Preventing settlement from MSE Wall?

    It is a railway with MSE walls on both sides of the alignment. As of now, the top of the pipe is 1.2m below the NGL. An 8m high fill with 9m width for a span of 40m would be added on top of the NGL. The fill would be supported by MSE walls. In short, there's already 1.2m soil on top of the...
  10. Jean_Wong

    Preventing settlement from MSE Wall?

    Good day! I am designing 8m high MSE Wall. There is a 0.6m diameter high pressure water supply pipe 1.2m below NGL, along the wall alignment. What could be done to prevent any settlement from the MSE Wall?
  11. Jean_Wong

    Load consideration and settlement for Abutment MSE Wall

    Good day! I am designing an mse wall abutment (stub abutment supported by deep foundation). I have already designed MSE walls before the bridge abutment (along/parallel to traffic). In my understanding, if the conditions for back-to-back MSE walls in the NHI code are satisfied (length of...
  12. Jean_Wong

    Unconfined compressive strength of rock?

    Thanks for the info! Some boring logs did not include qu of rock. The geotechnical engineer recommended the nearest boring log with qu values.
  13. Jean_Wong

    Compression test and flexural test of concrete

    Good day! We tried to replace some of the fine aggregates with different materials. In my understanding, the equipment we have can test concrete cylinders or cubes for compressive strength. The samples would be unreinforced. But for checking of flexure using centre load test, should we add...
  14. Jean_Wong

    Pile seismic inertial forces for bridges

    Thanks for the answer! Very informative :) Could you recommend a published reference for this so that I can show my senior? Thanks!
  15. Jean_Wong

    Pile seismic inertial forces for bridges

    Good day! For bridges, should the mass of pile or other foundations below ground surface be considered for response spectra or seismic analysis? Why or why not? Thanks!
  16. Jean_Wong

    Unconfined compressive strength of rock?

    Good Day! What is a good assumption for the value of qu of rocks?
  17. Jean_Wong

    Group Pile & Cap Bearing

    Good Day! I was assigned to determine the bearing capacity for a group of drilled shaft/bored piles. I used AASHTO LRFD 2012 as basis for my design. The cap would be 5m x 5m with 4 to 5 piles of 1m diameter. The cap thickness would be 1m to 2m. Is it correct that I based my reduction factor...
  18. Jean_Wong

    Railway barrier collision load

    Good day! I have been assigned to design barrier for a railway. Here is the definition from our design criteria: "For Piers and other guideway support element situated in less than 3m from the edge of adjacent highway shall be designed for horizontal static force of 1000kN, unless protected by...
  19. Jean_Wong

    Base wind pressure adjustment

    Thanks! I have adjusted the base wind pressures from the wind table. But adjusting the base wind velocity also adjusted the formula for the design pressures. The design pressures I was able to get were still the same.
  20. Jean_Wong

    Base wind pressure adjustment

    Good day everyone! I have to apply wind load on the bridge I'm designing using AASHTO LRFD 2012. The problem is that the base wind pressures on the code are based on a 100mph wind velocity (160kph). The area I'm designing it for has 200kph wind velocity, so the table would be inaccurate to...
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