{"id":6858,"date":"2022-01-01T12:05:38","date_gmt":"2022-01-01T12:05:38","guid":{"rendered":"https:\/\/www.systra.com\/ibt\/?post_type=projects&p=6858"},"modified":"2026-04-18T19:41:03","modified_gmt":"2026-04-18T19:41:03","slug":"sound-transit-east-link-extension-i-90-crossing-seattle-washington","status":"publish","type":"projects","link":"https:\/\/www.systra.com\/ibt\/project\/sound-transit-east-link-extension-i-90-crossing-seattle-washington\/","title":{"rendered":"Sound Transit East Link Extension I-90 Crossing – Seattle, Washington"},"content":{"rendered":"\n
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Technical details<\/div>\n \t
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Customer<\/div>\n\t
Sound Transit Central Puget Sound Regional Transit Authority<\/div>\n\t <\/div>\n
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Dates<\/div>\n

Construction Completed: 2023<\/p>\n<\/div>\n <\/div>\n

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Localisation<\/div>\n
Seattle, Washington<\/div>\n <\/div>\n
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Partners<\/div>\n
Prime Consultant: HNTB, Jacobs, Hatch, and Mott MacDonald, Contractor: Shimmick and Parsons<\/div>\n <\/div>\n
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Activity<\/div>\n
SYSTRA IBT's Role: Segmental Superstructure Design Consultant<\/div>\n <\/div>\n \n \n <\/div>\n\n\n\n
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DESIGN-BUILD<\/h2>\n\n\n\n

Main Span: <\/strong> 360 ft (109.8 m) main span, 245 ft (74.7 m) and 250 ft (76.2 m) side spans.<\/p>\n<\/div><\/div>\n<\/div>\n\n\n\n

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The Sound Transit East Link Extension I-90 Crossing expands the existing Seattle light rail system from Seattle across Lake Washington to Bellevue. <\/strong><\/p>\n\n\n\n

The 14 mi (22.5 km) alignment is primarily situated at grade with isolated elevated and tunnel sections. The I-90 crossing at the eastern terminus of the I-90 floating bridge is one of two long-span structures along the alignment. This cast-in-place segmental balanced cantilever bridge includes a 360 ft (109.8 m) main span with 245 ft (74.7 m) and 250 ft (76.2 m) side spans. <\/p>\n\n\n\n

The double-track alignment traverses a compound curve with a minimum centerline radius of 526 ft (160.4 m). The segmental super-structure consists of 175 ft 8 in (53.6 m) cantilevers off of each of the two main piers and 60 ft 6 in (18.4 m) and 65 ft 6 in (20.0 m) falsework sections at each end pier. Typical segments are 15 ft 4 in (4.67 m) long.<\/p>\n\n\n\n

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Featured Project<\/h2>\n
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