Question

tell the general principles of bridge planning and design. list them in order depending on their priority .why ?

Answer 1

For a ideal condition, detailed design process and conceptual design should not run simultaneously, to avoid the risk of expensive do-overs of detailed design operations or tasks. In addition to this, we can understand and also realise cost savings during conceptual design itself.

The main steps in the bridge conceptual design process are as follows:

Data collection:

• Assemble all relevant data for crossing site, stream, existing structure etc.
• Identify any upcoming or future highway plans

Site inspection:

• Visit site, record measurements and observations
• Include upstream and downstream crossings
• Preliminary location options can be identified

Arrange for technical report:

• Order site survey to supplement GIS dat sets
• Geotechnical investigation arrangement
• Environmental data inputs can be collected
• Any other data related to highway planning and operations can be collected

Hydrotechnical Assessment:

• collect data and assess existing structures and any other issues related to it
• Hydrotechnical design parameters are determined
• Identify river protection works, erosion/scour if any

Geometric Assessment:

• Existing geometry and issues are assessed
• Determine geometric design parameters  

Review technical inputs:

• Checking survey for accuracy and completeness, update can be done if necessary
• Geotechnical recommendations for slide mitigation, headslope ratios and penetration of pile are noted
• Environmental constraints like fish passage need, runoff quality etc. are considered
• Any other constraints are considered accordingly

Develop feasible options:

• You can coordinate with concurrent highway geometric design and planning, if any done by others
• Alignment, bridge opening, profile and protection options are combined to develop effective concept options
• Hydraullic analysis options have to be considered
• Sktech the key components like bridge opening, alignment, profile etc
• Analyse the costs and identify advantages and disadvantages for all the possible options

Evaluate options:

• Make a list and evaluate all the possible options
• input and opinion from others can be taken as a strctural review
• Identify optimal solution

Prepare initial report:

• Parameters established, options considered and work done are to be summarized
• Give recommended optimal solution with key sketches
• Obtain a review from experienced bridge conceptual designer for complete review and accuracy of plan

Obtain departmental guidance:

• Communicate with required project administrator or a sponsor at a project start or after completion of initial report
• Take approval or feedback from them to finalise the option and take required modifications if any  

Finalize documentation:

• Any modifications or changes are updated in initial report
• Finalize and drawings to fully document plan  

Follow up:

• Follow up in detailed design, tenders and various construction stages etc as required.