R&M Through the Years: Building the Pipeline
February 13, 2019
In celebration of R&M’s 50th anniversary, we are taking a look back at the projects over the last five decades that made R&M into the firm it is today. This month we take a look at the various pipeline-related projects R&M completed during the 1970s.
R&M’s involvement in the development and construction of the Trans-Alaska Pipeline (TAPS) grew rapidly from the firm’s initial geotechnical investigation work in 1969. During the next decade, R&M’s involvement extended to detailed pipeline route geotechnical studies, construction zone and workpad design, erosion control, restoration design and numerous special studies. Projects over these years included:
Geotechnical and Design Studies
In 1970, due to delays from technical, environmental and land status questions, TAPS went into a detailed study mode. These studies included numerous route geotechnical studies, special design-related studies for thaw settlement, and slope stability and pipeline support systems.
This phase continued until late 1973, when the required permits were approved and signed. Construction could now get underway.
Construction on roads, facilities and the pipeline began in April 1974 and finished in June 1977. R&M provided design and construction support services throughout this phase of work.
Workpad and Construction Zone Grading Plans
From 1973 to 1976, R&M provided support to Alyeska on design of the pipeline workpad and construction zone grading plans. This included erosion control, restoration and visual impact engineering. The firm also continued to provide support in geotechnical field studies and pipeline mode confirmation during construction.
Erosion Control and Restoration Work
From 1974 to 1977, R&M provided support during construction on erosion control and restoration work, including numerous projects during construction of the Valdez Pipeline Terminal. These included materials acquisition, testing and quality control for the construction materials site; site and foundation investigations for the proposed reinforced earth embankments; geologic inves¬tigations of bedrock conditions; geotechnical investigation and design of rock slopes and their reinforcements; design and installation of piezometer network for groundwater observation; and design and field modification of rock slope dewatering systems.
Special Design Efforts During Construction
R&M was also involved in several special design efforts for challenging pipeline sections due to the terrain they crossed. These included the Gulkana River Bridge Crossing and Thompson Pass High Line Buried Pipe Section.
For the Gulkana River Bridge Crossing, R&M developed a tied-arch design for the 400’ long bridge superstructure. The decision to use a bridge for this section of pipeline avoided numerous problems associated with the original buried underwater crossing concept. This bridge represented an innovative approach to solving problems of permafrost, environmental sensitivity, time schedule and materials limitations, as well as aesthetics. R&M won a 5th place award for the bridge superstructure design and a 3rd place award for the pile foundation design in the James F. Lincoln Arc Welding Foundation, 1976 Awards Program for Improvement Through Welding.
The movement of pipeline and related construction equipment to each site was a challenge during construction. At Thompson Pass, a particularly steep mountain face compelled the use of hi-lines for the transportation of materials and the construction operation. Designed by R&M to serve as overhead cableways, the two hi-line spans were 1,000’ and 1,450’ long and each possessed a 20-ton load capacity. Representing some of the longest span structures built in Alaska, the hi-lines were each supported by two steel towers with a maximum height of 170’. The moveable towers supported track cables anchored to post-tension concrete deadmen.
As-Built Documentation and Clean-Up Activities
From 1976 to 1977, R&M assisted in as-built documentation of the pipeline construction zone conditions and other clean-up activities. The pipeline construction was completed on May 31, 1977 and oil began flowing on June 20, 1977.
Next month, we are switching gears from TAPS activities to take a look at several bridge structures in the Anchorage area designed by R&M during this same decade.