Gusset plates are an important component of bridges. They are thick sheets of steel that join steel members together using fasteners and also strengthen their joint. Transportation agencies regularly evaluate and rate their inventories of gusset plate connections using visual inspection, which is very costly. To address this issue, we...
Bridge inspections are vital for monitoring the health and serviceability of transportation infrastructure throughout the world. However, inspections can be logistically-challenging, expensive, and dangerous. For example, inspections may require climbing, as well as the use of scaffolding, ladders, rescue boats, bucket trucks, and/or under-bridge inspection vehicles. Small, multirotor unmanned aircraft...
Sampling studies were conducted to compare the efficiency of the four officially recommended methods of sampling small seeds: automatic sampling--at two sampling speeds, hand sampling, Nobbe tier sampling, and stick trier sampling. Synthetic lots of orchard-grass, ryegrass, Kentucky bluegrass, and alfalfa seed were prepared containing known numbers of the common...
A comparison of two procedures which allocate inspection effort
within a production sequence is presented here. The concern
for quality and the need to hold down the costs of quality has resulted
in mathematical models which locate inspection so that the
desired quality is attained at a minimum cost.
In...
The evaluation of pavement condition is an important part of pavement
management. To evaluate a pavement, a distress survey has been performed mainly by
manual field inspections. Several automatic pavement evaluation systems have been
developed to overcome the drawbacks of field inspections. Automated evaluation
systems, however, imply their own limitations...
A methodology was developed to permit rectification and metrification of digital images of steel truss gusset plate connections. The approach will enable rapid and accurate collection of field measurements as compared to traditional methods to enable structural evaluation of gusset plate connections. The program enables the operator to quickly create...
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
Bridge inspection is a critical task needed to monitor bridge quality and serviceability. In the U.S., 40% of bridges are more than 50 years old while most bridges are typically designed for a lifespan of 50 years. 9.1% of the 614,387 bridges across the U.S are considered structurally deficient. These...