The “internet of things” has revolutionized the methods in which many industries have optimized performance and component defect detection by providing real-time feedback through the implementation of data processing and wireless communication. Despite these advancements, the railway industry has lingered stagnant in its approach of adopting these advanced prognostic detection systems, and instead relies on discretely (25–40 miles) placed trackside condition monitoring systems, aka wayside. These wayside systems are primarily used to detect abnormal operating conditions in railcar rolling stock components. However, while they have been used for decades to address imminent threats to derailments and/or safety, they have unfortunately been shown to erroneously flag and misdiagnose components. These “false positive” cases usually result in unnecessary and costly delays and train stoppages. In worst case scenarios, these wayside systems have been known to mis-identify problematic components which can potentially lead to catastrophic derailments, risking property and safety. Overall, these limitations to established methods, and current technological innovations, allow for the introduction of a pioneering technology that addresses these deficiencies to enable constant, reliable, and precise onboard component health monitoring through vibration and temperature tracking. With these advancements, railroad car owners and operators can preemptively assess any rolling stock maintenance issue well in advance of an anticipated catastrophic failure. To validate the efficacy of these onboard sensors, a field study was conducted using 40 such monitoring devices that were affixed to the bearing adapters of randomly selected railcars in a dedicated coal service route. After the span of two months of ongoing testing, three wheelsets were selected for removal based on data collected that indicated non-normative operating conditions. The wheelsets were inspected, analyzed, and the corresponding bearings were shipped to the University Transportation Center for Railway Safety (UTCRS) for laboratory evaluation and testing. This paper summarizes some of the preliminary results acquired from this field test and provides a comparison between the field and laboratory data, demonstrating their agreement and the prospective integration of these sensor technologies into the rail industry.

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Because soil is a heterogeneous media, pile installation response does not always proceed according to plan. When driving performance variability occur, the capacity of the piling must be determined and the cause of these discrepancies analyzed. Procedures for evaluating available soil borings, geophysical information and pile driving records to determine pile capacity are detailed. BACKGROUND During installation of a four pile jacket in the East Cameron area of the Gulf of Mexico, difficulties were encountered in reaching the design penetration of 323 feet. Piles 1 and 4 reached refusal after the final section was added when driving with a Menck 3000 hammer. A Menck 7000 hammer was tried on pile 4 and also met refusal. The typical definition for refusal used by installation contractors for a Menck hammer is 150 blows per foot for five feet or 250 blows per foot for restarting a pile. This definition differs form the API RP 2A(Ref. 1) recommendation of 300 blows per foot for five consecutive feet or 800 blows for one foot of penetration. This lower blow count for refusal is favored to prevent damage to the hammer which can be caused by excessive pounding with the hammer. In this paper the former definition for refusal was used. Adding the final section and driving to refusal gained less than 10 feet of additional penetration and left a weld joint at a poor location for proper connection to the jacket. It was decided to drive piles 2 and 3 and to terminate pile driving after installation of the fourth section at a penetration of about 258 feet. This final penetration would leave the heavy wall pile section high in the profile, but in an acceptable location to provide the design lateral support because of proper underdrive design. The predicted pile capacity based on the nearby boring provided a capacity of about 5400 kips. This capacity of 5400 kips was sufficient for minimum design requirements but a determination of the as installed capacity consistent with normal design procedures was required to determine maximum allowable loading conditions. Final pile penetrations (measured from the seafloor) for piles 1,2,3 and 4 were 268.5, 259, 258.5 and 263.5 feet respectively. QUESTIONS TO BE ANSWERED The difficulties during installation on this project raised several questions on the design and installation of a jacket. The questions that were asked of Seafloor Engineers as geotechnical consultants and are addressed in this paper are as follows:What is the pile capacity of the piles in their as built condition?Based on a review of the boring log near the location, no driving problems were anticipated. Why did driving problems occur?

A stress-path testing program was proposed and performed to investigate shear strength and deformation behaviors due to an open cut excavation in overconsolidated clay. Stress changes due to the staged excavation for different locations of the slope were estimated and applied on undisturbed specimens using a triaxial testing system. Axial load, chamber pressure, and back pressure were actively controlled to implement the various stress paths. Vertical and horizontal deformations were monitored during the stress paths, and then an undrained compression or extension shearing stage followed. Test results for three cases from the testing program: the crest and the toe of the slope, and the base of the excavation are presented. The clay deposit was found to be non-expansive, based on the deformation behaviors. Effective stresses appeared to govern the vertical and horizontal strains. Failure envelopes for compression and extension were established from the stress path testing. The mobilized undrained shear strength from the stress path approach is substantially lower than one from the conventional method.