Operational condition assessments, using a discrete rating system, are frequently used by field engineers to assess inland navigation assets and components. Challenges such as the occasional inability to perform inspections (such as the case with locks watered in an operational state) and protocol requirements requiring ratings even when they aren't inspected lead to highly abstracted inspection data, which are also very prone to human error and misinterpretations due to inspections protocol. On the other hand, some navigational locks are equipped with structural health monitoring (SHM) systems to continuously perform assessments from data obtained in situ . This paper aims to develop a novel hybrid damage prognosis framework for miter gate component of navigational locks, by mitigating effects of human errors on the condition assessment and integrating the highly abstracted inspection data with the SHM. It overcomes two main challenges, namely (1) there is no physical or empirical model available to model the loss-of-contact degradation in the gate, and (2) the mismatches between the inspection data and the SHM system due to data abstraction. A practical case of monitoring loss-of-contact quoin block demonstrates the efficacy of the proposed framework.

Kaleidocycles are continuously rotating n-jointed linkages. We consider a certain class of six-jointed kaleidocycles which have a spring at each joint. For this class of kaleidocycles, stored energy varies throughout the rotation process in a nonconstant, cyclic pattern. The purpose of this paper is to model and provide an analysis of the stored energy of a kaleidocycle throughout its motion. In particular, we will solve analytically for the number of stable equilibrium states for any kaleidocycle in this class.

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The purpose of this Coastal and Hydraulics Engineering Technical Note (CHETN) is to provide guidance on the applicability of trunnion friction monitoring at navigation dams with Tainter gates. BACKGROUND: The U.S. Army Corps of Engineers (USACE), as part of its Civil Works mission, operates and maintains approximately 700 dams. These dams provide many U.S. benefits including flood protection, water supply, hydropower, recreation, fish and wildlife conservation, and inland waterway navigation capability. The USACE dam portfolio averages over 50 years of age, and over half of the USACE-managed dams have exceeded their design service life. Currently, available funding is less than that needed to fully repair the dam portfolio. It is crucial that USACE direct repair funding and efforts at the most critical infrastructure to maximize safety and national benefit. Structural health monitoring (SHM) techniques can be used to help identify opportunities for just-in-time maintenance and repair.