Orange County NC Website
Browse       Search
:n <br />r� <br />Bridge Conditions <br />Bridges are a necessary and unique element of a highway <br />system. They represent the highest unit investment of all <br />elements of the system. If any inadequacies or deficiencies exist <br />in a bridge, the value of the total investment of the system is <br />reduced. The community welfare can be disrupted if the structural <br />system of a bridge fails, but more importantly loss of life can <br />also occur. For these reasons, bridges must be constructed to the <br />same or higher design standards as the highway.system of which <br />they are a part. <br />Congress enacted the National Bridge Inspection Program <br />Standards on April 27, 1971, implementing the Federal Highway Act <br />of 1968. These standards require that "all structures defined as <br />bridges located on and of the Federal -Aid Highway Systems be <br />inspected and the safe load carrying capacity computed at regular <br />intervals, not to exceed two years." A sufficiency index number, <br />has been calculated for each bridge for the purpose of <br />establishing eligibility and priority for replacement. The <br />bridges with the highest priority are replaced as Federal -Aid <br />funds and State funds are made available. Additional funds have <br />recently been provided by Congress specifically for bridge <br />replacement. <br />A sufficiency rating is used in the analysis to determine the <br />deficiency of a particular bridge. The sufficiency rating is a <br />method of evaluating factors which are indicative of bridge <br />sufficiency to remain in service. Some factors used are: <br />structural adequacy and safety, serviceability and functional <br />obsolescence, structure type, and traffic safety features. This <br />method yields a percentage in which 100 percent would represent an <br />entirely sufficient bridge and zero percent would represent an <br />entirely insufficient or deficient bridge. A sufficiency rating <br />of 50 percent or less qualifies for Federal Bridge Replacement <br />funds. <br />Table 7 shows functionally obsolete bridges with sufficiency <br />ratings of 50 percent and less, with a reference to.their location <br />on Figure 6. There are 119 bridges located in Orange County, with <br />32 functionally obsolete bridges with a sufficiency rating of 50 <br />percent or leas. There are currently four bridge projects <br />included in the current Transportation Improvement Program. <br />Table 7 also shows structurally deficient bridges, with a <br />reference to their location on Figure 7. <br />25 <br />