11/05/2026
By Thomas Dugan

The Francis College of Engineering, Department of Civil and Environmental Engineering, invites you to attend a master's thesis defense by Timothy Brigham, titled “Measuring Tilt in the Abutment Walls of a Long-Span Skewed Integral Abutment Bridge (IAB) in Hartford, Vermont, During the Construction Phase.”

Details

  • Date: Thursday, Nov. 19, 2026
  • Time: 11:30 a.m.
  • Location: Perry Hall, Room 215

Abstract

Integral abutment bridges (IABs) are jointless bridges where the deck is continuous and connected integrally with the abutment walls, typically supported by a single row of flexible piles. In IABs, the lack of expansion joints can reduce maintenance costs but also causes the thermal expansion and contraction of the bridge’s superstructure to be passed directly to the substructure. There are many factors that can impact the behavior and design of IABs, such as span length, skew angle and backfill conditions. In addition, if the stiffness of the substructure varies from one abutment to the other, the behavior becomes more unpredictable, creating the need for additional research.

This thesis details the monitoring of the tilt in the abutment walls and wingwalls of Hartford Bridge #7 in Vermont during its construction phase. This bridge is a 550-foot-long, three-span (160–230–160 feet), 20-degree skew integral abutment bridge. The bridge’s superstructure consists of four steel girders with an additional splayed girder to support the sidewalk at abutment 2.

The substructure consists of two abutments, each supported by ten W12×152 steel piles and 45 inches of EPS geofoam between the abutment walls and backfill. However, the abutment wall dimensions, pile length and pile installation methods vary due to the differing soil profiles at each abutment. The unconventional and often asymmetric design of Hartford Bridge #7 exceeds many design guidelines, providing an excellent opportunity to study the behavior of such a complex IAB.

The objective of this research was to observe the tilt experienced by the bridge and record the change in tilt as the bridge experienced changes in ambient temperature. To achieve this, 12 MEMS tiltmeters were installed across the bridge, with four sensors installed across each abutment wall and a single sensor at each wingwall. Manual and automated readings for tiltmeters were collected and organized before being compared against each other to review data trends and ensure that no disruptions occurred during the transition to automated readings. Following this, the tiltmeter readings were collected, examined and plotted monthly, comparing the readings at the top and bottom of each abutment wall as well as the obtuse and acute corners of the walls. Combining these observations with the changes in ambient temperature at the bridge allowed for an understanding of how the abutment wall rotation tilt would react to changing temperatures throughout the year.

All interested students and faculty members are invited to attend.