This study is in consideration of the spread of COVID-19, the related various government responses, and how these responses and other demographic variables affected the spread and severity of the virus on a domestic (United States) and international level. During the last few months, the virus has spread from its...
What sets this initiative apart is the commitment to deepening ties between African and non-African institutions and making them more seamless and routine. There is a need to make this case to US institutions - lobbying them to digitize/provide open access, creating relationships with African institutions, prioritizing partnerships and academic...
To check that changes in prevalence rates over time were not the result of changes in measurement, we conducted sensitivity analyses. We created a set of adjusted scoring algorithms to maximize comparability among the DISC- 2.3, DISC-IV, and DIS-IV criteria while minimizing alterations. This file shows the adjustments made to...
A study is conducted to determine the effects on the early hydration kinetics and
compressive strength by seeding of Portland cement and alkali-activated blast furnace
slag with a pure form of calcium silicate hydrate (C-S-H). The effects of C-S-H seeding
during the early nucleation and growth period of each type...
The segmental prestressed concrete box girder of Koror-Babeldaob (KB) Bridge in Palau, which had the record span of 241 m (791 ft.), presents a striking paradigm of serviceability loss due to excessive multi-decade deflections. The data required for analysis have recently been released and are here exploited to show how...
The in-depth inspection by WIDOT detected two sites that had visible cracks in the stiffener-to-hanger diaphragm welds, the east side of Hanger 6 in the north tie girder, and the east side of Hanger 4 in the south tie girder. Additionally, many ultrasonic indications were detected by WIDOT in the...
This report describes the results of applying acoustic emission (AE) testing to the trunnion shafts of the East Span of the 1-5 Interstate Bridge. The tests were done at the request of Oregon DOT personnel to determine if active fatigue racks are present in the subject shafts.
The U.S. has 542,000 bridges that consume billions of dollars per year in construction, rehabilitation and maintenance funds and which are the lifelines of U.S. commerce. The 1992 ISTEA (fntermodal Surface Transportation Efficiency Act) mandates the implementation of a quantitative computerized bridge management system by I 996. A prime need...
This study tested a dynamic traffic assignment (DTA) model as a tool for pre-planning strategies for managing major freeway incidents. Incidents of varying scale and duration were modeled in the northern Chicago highway network, and the impacts of incidents and response actions were measured in terms of both lane-mile-hours of...
The mission of the Infrastructure Technology Institute is to develop strategies and tools
to protect and improve the condition, capacity and performance of the nations highway, railroad,
and mass transit infrastructure systems. The Institute does this through the development
and deployment of (1) advanced technologies for structural health monitoring, (2)...
Few would argue that concrete is an important and useful material: after all, concrete is the backbone of the world’s infrastructure, used in vast amounts to make roads, buildings, bridges, and other structures. But sometimes familiarity breeds contempt. To most people, concrete is simply that boring grey stuff that we...
The objective of this program is to measure the changes in the properties of the C-S-H gel phase in cement paste as a function of the Ca/Si ratio. The motivation is to better understand the hydration products that form in blended cements with lower Ca/Si ratios than portland cement. The...
This final report provides information about TEA-21 [Transportation Equity Act for the 21st Century] funded projects designated A433, and A495 "Evaluation of Capacity of Micropiles Embedded in Dolomite". The report was submitted to the Infrastructure Technology Institute at Northwestern University by Richard J. Finno on September 20, 2002.
Non-destructive evaluation (NDE) techniques have been used for a number of years to provide quality control of construction procedures for drilled shafts and driven concrete piles. In particular sonic echo and impulse response methods have been used extensively to check lengths and continuity of newly-installed foundations. In recent years, the...