Abstract "Seasonal temperature changes, traffic loading, and compressible foundation can induce bridge
abutment movements, which result in differential settlement between bridge and abutment, i.e.,
bump. Bumps create a hazardous condition for vehicles, which increases motor vehicle fatalities
and costs for maintenance and repair. The bump at the end of the bridge is a universe problem
for transportation infrastructure around the world including the US. It has caused many motor
vehicle fatalities and costed more than 100 million dollars annually to maintain and repair in the
US alone. A laboratory study done by this research team has demonstrated the effectiveness of
using geogrid reinforcement with geofoam to mitigate the bump problem when the abutment is
on a firm foundation. Lightweight backfill is expected to reduce the settlement of bridge
abutments on a compressible foundation; therefore, the combination of lightweight backfill with
geosynthetics is expected to eliminate the bump even when the abutment is on a compressible
foundation. This combined technology needs to be verified by a numerical study and then a field
study in the future. The outcome of this project will lead to the development of innovative and
sustainable technology for eliminating the bump at the end of the bridge. The successful
development of this technology will improve the safety of the bridge approach and the economy
of bridge maintenance and repair."
Description "deliverables:
a) Task 1: a comprehensive literature review will be performed to understand the
state of research and practice in bridge abutments in terms of bump problems,
backfill, and mitigation techniques and to collect data of model tests, field case
studies, and numerical results. The expected task deliverable is a summary of
the literature review.
b) Task 2: Numerical models will be developed and calibrated with the collected
data in Task 1. The expected task deliverable is calibrated numerical models.
c) Task 3: A parametric study will be conducted to examine different influence
factors on the performance of bridge abutments with lightweight fill and geosynthetics. The expected task deliverable is numerical models and numerical
results.
d) Task 4: The numerical results will be analyzed to identify the important key
influence factors on the performance of bridge abutments. The expected task
deliverable is a list of key influence factors.
e) Task 5: A final report will be developed to document the results and findings from
Tasks 1 to 4 and provide recommendations for future research and practice. The
expected task deliverable is a final report."
Objective "The expected result is a combined technology of using lightweight backfill and
geosynthetics to construct safe, sustainable, and resilient bridge abutments to eliminate
the bump at end of bridge."
Impacts/Benefits "This project addresses a structural-geotechnical-transportation interaction problem. The
knowledge gained from this project can be incorporated in courses related to bridge
design, foundation design, and highway design, which will enable the future workforce
properly address this complicated problem.
State departments of transportation (DOTs) and railway authorities have constructed
many bridge abutments along highways and railways. The research team will share the
research results with all state DOTs and railway authorities but will work with selected
state DOTs or railway authorities for possible field studies to verify this proposed
technology in field projects. The research team will present the research results at
relevant conferences (e.g., the annual Transportation Research Board meeting, the
Southwest Highway Geotechnical Engineering Conference, and the annual Kansas
University Geotechnical Engineering Conference)."