500 Structures

501 Structures - General

Engineering

When the Contractor performs survey work, the Engineer shall verify the Contractor’s accuracy by observation of the work and review of notes.  A state survey crew should be available to check any part where this accuracy is not obtained.  The Contractor’s surveyor should cooperate with the Engineer and provide the notes on critical work, such as bridge seat elevations, profiles of beams or girders, and grade for finishing the deck for review and concurrence.  Information that indicates the elevation of bridge seats and deck grades have been properly set and must be recorded in the project file.

Relations between the Engineer and surveyor should be in the spirit of cooperation toward achieving the common goal of bridges constructed of specified quality, in plan location, and on proper grade that will benefit both the state and the Contractor.

 

Working Drawings and Calculations (501.05)

When railroad involvement is required, as specified in 501.05.A, it is the Contractor’s responsibility to submit working drawings to the involved railroads for acceptance at least 50 days before construction begins.  The Contractor shall supply the Engineer with documentation proving railroad acceptance.  Department acceptance is not required. The following working drawings should be submitted to the Engineer at least 7 days before construction begins.  These working drawings shall be prepared by an Ohio Registered Professional Engineer (PE) and checked by a second PE.  No Department acceptance is required. Lack of departmental acceptance does not supersede the Engineer’s authority per C&MS 105.04.

1.      Sheeting and excavation bracing which impacts active traffic or with an exposed height over 8 feet or when required by contract, except when a complete design is shown in the plans.

2.      Demolition of structures over or adjacent to active traffic.

3.      Falsework for cast-in-place concrete slab bridges.

4.      Erection of steel or precast concrete structural members.

5.      Jacking and support of existing structures.

6.      Construction loads applied to a structure during construction in excess of 75 percent of legal load.

7.      Structures for maintaining traffic.

Although no Department acceptance is required, these working drawings should be utilized in the field as the standard to judge whether the Contractor is performing the work correctly. 

Stop all operations that do not follow the prepared working drawings. The Contractor must submit to the Engineer any revised working drawings, which are prepared by an Ohio Registered Professional Engineer, 24 hours before construction on the deviated work begins.

If the Contractor requests to weld to a main structural member that is not shown on the Contract drawings, he must submit a plan to the Office of Structural Engineering for acceptance at least 20 days before construction begins.

If a Contractor has to perform corrective work on structures items, the Contractor must submit three copies of a corrective work plan (CWP) to the Engineer, including supporting calculations prepared by an Ohio Registered Professional Engineer. The Engineer will submit the CWP to the Office of Structural Engineering for review and acceptance prior to performing corrective work.

When traffic is maintained while an overhead structure is being removed, platforms, nets, or other devices must be provided to safeguard the traveling public from falling objects that might fall directly onto the roadway below, be deflected toward the traffic, or bounce into traveled lanes.  Removal of superstructure concrete and structural steel shall, in no case, take place directly over traffic due to the possibility of large pieces falling through the protective devices.

 

Documentation Requirements - 501 Structures

This section outlines the Contractor’s requirements for fabrication, shop drawings, material certification, and erection procedures.

Use Erection Checklist Form CA-S-20