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Overexertion injuries comprise the largest category of nonfatal injuries among construction workers. These injuries typically occur when the biomechanical stresses associated with tasks such as lifting, carrying, pushing, etc., exceed the worker’s strength capacity. Two studies were conducted to measure the whole-body isometric strength capability of 56 construction workers. The first study examined the effect of four typical postures (2 symmetric lifts and 2 asymmetric lifts) associated with scaffold end frame disassembly. The effect of posture on isometric strength capability was significant; the strength capability ranged from 366 N to 676 N. The second study evaluated the effect of hand separation distance (46 cm, 86.4 cm, and 116.8 cm) and vertical hand placement (knuckle, elbow, and acromial heights) on isometric force during symmetric lifting postures. The interaction effect of hand separation distance - vertical hand placement on isometric strength capability was significant.

Yard hostlers are tractors (switchers) used to move containers at ports and storage facilities. While many speed-time driving cycles for assessing emissions and performance from heavy-duty vehicles exist, a driving cycle representative of yard hostler activity at Port of Long Beach, CA was not available. Activity data were collected from in-use yard hostlers as they performed ship loading/unloading, rail loading/unloading and other yard routines, primarily moving containers on trailers or carts. The activity data were then used to develop four speed-time driving cycles with durations of 1200 seconds, representing light and heavy ship activities and light and heavy load rail activities. These cycles were constructed using actual speed-time data collected during activity logging and the cycles created were statistically comparable to each subset of activity data.

Air cargo containers are used to load freight on various types of aircrafts to expedite their handling. Fuel cost is the largest contributor to the total cost of ownership of an air cargo container. Therefore, a better fuel economy could be achieved by reducing the weight of such containers. This paper aims at developing innovative, lightweight design concepts for air cargo containers that would allow for weight reduction in the air cargo transportation industry. For this purpose, innovative design and assembly concepts of lightweight design configurations of air cargo containers have been developed through the applications of lightweight composites. A scaled model prototype of a typical air cargo container was built to assess the technical feasibility and economic viability of creating such a container from fiber-reinforced polymer (FRP) composite materials. The paper is the authoritative source for the abstract.

The objective of this paper is to devise innovative lightweight design concepts for heavy vehicle structures. A 1 to 4 prototype of a trailer was built to assess the feasibility of use of polymer composites and to have first hand experience with possible bonding methods to join the design parts. In the current trailer configurations, floor assembly constitutes 70% of the overall weight. The results indicated that sandwich technology with a lightweight core that adds flexural stiffness to the overall design provides a solution to decrease the weight of heavy vehicle systems.