Journal of Cold Regions Engineering

In this paper, a diffuse interface model, namely, the phase-field model (PFM) is proposed to model asphalt concrete cracking subjected to shear loading (Mode II) at low temperature. This method describes the microstructure of asphalt concrete using a phase-field variable. To account for the growth of cracks, a nonconserved Allen-Cahn equation is adopted to evolve the phase-field variable. The whole PFM system is implemented and solved in a finite-element software program. The simulation results are then validated by semicircular bending (SCB) tests at $-20°\mathrm{C}$ and four-point bending tests at $-10°\mathrm{C}$. It is discovered that PFM simulations of crack initiation and propagation in asphalt concrete at low temperature agree very well with the experimental results.

A hand-driven friction-sleeve-equipped minipenetrometer was assessed for its efficacy in determining snow physical properties. Numerous factors were investigated including the effect of penetration rate, penetrometer effective diameter, compaction ahead of the penetrometer, distance for representative resistance to be mobilized, and the effect of snow density on penetrometer tip resistance and sleeve friction. Analysis suggests that consideration of additional friction-sleeve data may provide greater insight into snow physical properties compared to consideration of tip-resistance data alone. A friction-sleeve-equipped penetrometer provides valuable data in snow and firn beyond that obtainable through the use of a device measuring only penetrative resistance at the tip.

Pervious concrete placements in many locations are subject to cold weather conditions and varying levels of clogging and rejuvenation. This study focuses on field surface hydraulic performance in correlation with changes in ambient temperature, clogging, and performance after rejuvenation. Previous laboratory tests indicate that there may be some reclogging in pervious concrete after rejuvenation. It is also hypothesized that colder water temperatures may reduce hydraulic performance. A modified version of a standard surface infiltration test was used to test infiltration rates at four locations on a placement in Pullman, Washington, over the course of two winters. It appears that the surface infiltration rates may vary slightly with temperature variations, but insignificantly with respect to the clogging over time from runon and atmospheric deposition. However, it is recommended that infiltration testing carried on in warmer months be used conservatively in areas that experience colder temperatures. In addition, it is recommended that a second infiltration test be performed when evaluating performance, especially after rejuvenation, as some clogging of new or dislodged fines might occur in the first test.

In designing flood control projects, engineers must show that the proposed project provides a flood damage reduction benefit in economic terms. For ice control structures, however, cost benefits have rarely been calculated at the time of construction because of the uncertainty associated with ice-affected flooding. This work presents a quantitative method for assessing the financial benefits of such structures since installation. Oil City, located at the confluence of the Allegheny River and Oil Creek in Pennsylvania, experienced frequent ice jam and ice jam flooding events prior to the design and installation of two ice control structures (ICS) in the 1980s. The ice control structure on the Allegheny River is a floating boom meant to encourage freezeup and development of a thermal ice cover, reducing frazil deposition in a pool downstream of the confluence. The Oil Creek ICS is a concrete weir designed to hold back or delay ice runs down to the confluence where they traditionally jam. Using historical ice jam data, criteria were developed to estimate when a jam was likely to occur. Those criteria were applied to the post-ICS period, and dates when an ice jam was likely were modeled without and with an ICS in place. A hydraulic model was calibrated and used to model post-ICS jams for without-ICS and with-ICS conditions. Financial damages in each case were estimated from the modeled peak stage resulting from an ice jam event. Benefits were then calculated by comparing financial damages resulting from the peak stage with the structure in place to that without the structure for the same event. The objective of this study is to implement that method for calculating annual benefits and to estimate the without-ICS and with-ICS stage at Oil City for each year that the ICSs have been in place. This example application of estimating cost benefits of a structure after installation for examining impacts presents a method for justifying maintenance and rehabilitation costs of ice control structures and future design and construction. It is estimated that the Oil City ICSs have provided $23.5 million in flood damage reduction since installation.

Alaska’s economy is tied to oil production, with most of the petroleum coming from the Prudhoe Bay oil fields through the Trans-Alaska Pipeline System. Deadhorse, an industrial town located on the North Slope, provides support to the oil industry. The Dalton Highway is the only terrestrial connection between Deadhorse and other cities in Alaska. During winter 2015, the road was impassable twice for 12 days total due to winter overflow from the Sagavanirktok River. During spring breakup, unprecedented flooding occurred near Deadhorse, caused by ice accumulation near the road and fast snowmelt due to warm air temperatures, which resulted in the road’s closure for 18 days, the first time since the highway was built in 1976. Presented in this article are antecedent hydrometeorological conditions in the Sagavanirktok and neighboring watersheds, a summary of infrastructure protection measures implemented before breakup, hydrologic data collected during breakup, and damage caused by the spring flood to the infrastructure.

This research examines the vulnerability of the winter maintenance salt supply to depletion and the associated risk costs in Ohio using Ohio Department of Transportation (ODOT)-specific data pertaining to the amount of salt storage, number of trucks, and lane kilometers maintained by each county. These data were combined with the number of snowfall events in each county to determine the failure probability. The results indicated that the probability of exceeding the salt capacity ranged from less than 0.01 to 61%, with an average of 23.1%. Sensitivity and importance analyses were conducted to determine the change in probability of exceedance due to a one-unit change in each parameter and to examine the influence of each random variable in the reliability analysis on the variance of the limit state, respectively. The parameter with the highest importance was the salt applied during light snowfall, while the brine applied has a low importance. Annual risk costs were estimated using the purchase and storage costs of salt and the total cost was then determined to estimate the optimal salt supply for different regions of Ohio based on the amount of snowfall and number of snowfall events.

Studies have shown that the roughness coefficient of the ice cover changes over time and space. Such a variation can substantially affect the design of channel dimensions to handle the design discharge. This paper presents an optimization model that incorporates the uncertainties of the roughness coefficients of both ice cover and channel bed. The model determines the best hydraulic section by minimizing the cross-section area subject to the design discharge. The nonlinear discharge equation is linearized using a Taylor series expansion. The linearity and normality assumptions of the discharge constraint are verified, and the results show that the assumptions are very accurate. The proposed chance-constrained model represents a novel step toward incorporating uncertainty in ice-covered channel design.