Hayward Baker Inc., headquartered in Odenton, Md., has received the 2012 Project of the Year Award from the Ridge Branch of the American Society of Civil Engineers (ASCE).
The award, given for a highly innovative slime
remediation project, was presented to Ed J. Garbin Jr.,
chief engineer of Hayward Baker’s southern region, Feb. 23 during the ASCE
Ridge Branch’s annual awards banquet in Lakeland, Fla.
In being selected for the award, Hayward Baker was cited
for its technical leadership in employing highly effective and cost-efficient
Rigid Inclusions (RI) technology in the construction of a major road extension
in Lakeland, Fla. The East-West Connector project involved extending Edgewood
Boulevard to the west, from Harden Boulevard to South Florida Avenue.
The project’s scope included constructing a new roadway
embankment through an area formerly strip-mined for phosphate ore. A portion of
the proposed roadway alignment was situated over settling ponds remaining from
the former mining operation. These ponds contained up to 40 feet of very soft
waste phosphatic clay (slime). This very weak and unstable material needed to
be modified in order to make the land suitable to support the roadway
Hayward Baker’s solution was an innovative RI ground
improvement system, proposed as the most effective and cost-efficient way to
ensure long-term stability in an environment of poor soils beneath the new
roadway embankment. As a proven solution in Europe for supporting embankments
on soft soils, RIs reinforce buried soft compressible soils by transferring
stresses from a near-surface granular soil to a deeper competent stratum.
Compared to alternative stabilization methods, they often are a significantly
less costly solution.
Employing RI technology for ground improvement involves
using high-modulus columns constructed through compressible soils to reduce
settlement and increase bearing capacity. These are arranged in a grid pattern,
and extended to the competent bearing stratum. As part of the system, Hayward
Baker designed a reinforced earth bridging layer directly atop the grid of RI
elements to ensure uniform stress distribution to all elements. Kimmins
Contracting Corp. of Tampa, Fla., constructed this geosynthetic-reinforced,
compacted aggregate platform. Arching within this layer distributed all
overburden stresses to the RI elements.
The work was completed within five months’ time. Due to
thorough pre-planning and the RI design calculations conducted by Hayward
Baker, the project proceeded smoothly according to plan, with no unforeseen
developments or project delays encountered.
James Hussin, a director at Hayward Baker, says, “We’re
pleased that the ASCE has cited this project for special recognition. Rigid Inclusions
technology was ideally suited for the construction requirements of the
East-West Connector at a large cost savings to the owner. RI elements represent
an increasingly popular ground modification method for projects of this type.”
Kimmins Contracting served as the primary contractor on
the East-West Connector project. In addition to Hayward Baker, other project
participants included a pair of Tampa-based firms – Atkins North America for
engineering consulting, and Tierra Inc. for geotechnical/materials testing and