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Fatigue Analysis Of The I-75 Bridge Over The Kentucky River At Clays Ferry, Theodore Hopwood Ii, Vishwas G. Oka

Kentucky Transportation Center Research Report

Fatigue analysis was performed on AASHTO category E welded connections on the southbound I 75 bridge over the Kentucky River at Clays Ferry, Kentucky. That analysis was based on the stress-range histogram data provided by Law Engineering of Louisville, Kentucky. That data were obtained from strain gages installed at 6 test locations on the downstream truss.

The fatigue analyses consisted of safe-life and fatigue-crack growth analyses. Safe-life predictions were based on AASHTO fatigue design (SN) curves. To use those curves, equivalent constant-amplitude stresses were derived from the stress histograms. Those stresses and loading frequencies were modified to reflect anticipated increases …

Calcium Nitrite As A Corrosion Inhibitor In Reinforced Concrete Bridge Decks, Theodore Hopwood Ii, David Q. Hunsucker, Edgar E. Courtney

Kentucky Transportation Center Research Report

The use of calcium nitrite es a corrosion-inhibiting admixture in reinforced concrete hes been studied on two bridges· the Kentucky 152 Bridge in Washington County and the Gose Road Bridge in Boyle County. Calcium nitrite was added to concrete used in the slabs, diaphragms and barriers of the KY 152 bridge and only in the slab of the Good Road bridge.

Construction of both structures was monitored in the fall of 1986. Placement of concrete on both bridges was satisfactory; however, problems were experienced in finishing the concrete. The finishing problems were related to: 1) concrete 'stickiness', 2) use of …

Excessive Beam Deflections On The Ky-52 Bridge Over Dix River (Boyle-Garrard County Line), Theodore Hopwood Ii, Vishwas G. Oka, David Q. Hunsucker, James H. Havens

Kentucky Transportation Center Research Report

Upon rehabilitation, beams and deck of the Ky 52 bridge over Dix River were observed to have excessive deflections. An investigation of the problem included field inspections, structural analyses, and interviews with relevant KYDOH and other personnel.

Field measurements were made of the beam deflections. Those were compared to construction field measurements and dead-load calculations.

The beam deflection problem is attributed to 1) a failure to provide for sufficient camber in the beams to accommodate for construction dead loads, and 2) pre-existing sags in the beams when placed prior to casting the deck. Part of the deck deflection problem can …