|
|
|
|
|
|
|
Central Artery/Tunnel Contract No. C09C1 Interstates 90 & 93 Interchange Boston, Massachusetts |
Back to Project List
|
|
|
 |
|
|
Drilled Micropiles |
|
Sixty-seven ton drilled micropiles are installed to underpin bridge structure in less than 25
feet of headroom.
|
|
|
Project Overview: |
|
Layne GeoConstruction designed and constructed a value-engineered drilled micropile system for both
temporary underpinning and permanent support of bridge foundations at a major interstate highway
interchange. The value engineered proposal replaced the contract design of driven piles. Drilled
micropiles were installed in low headroom and were determined to be a more cost effective solution.
The drilled piles were installed to depths of 14 feet through urban fill, marine clay, glacial till,
and bedrock. The drilled piles were 9 inches in diameter and achieved their design capacities of 67
and 100 tons in the weathered rock stratum. Load testing was successfully performed to 134 and 200
tons, respectively.
|
|
|
Value of Work Performed: |
|
$1,000,000 |
|
Project Duration: |
|
18 months |
|
Project Completion Date: |
|
November 2000 |
|
Project Reference: |
General Contractor:
Modem Continental Construction Co. Inc.
|
|
|
|
|
|
