| Structure/Roadway Inspector.
Construction Cost: $14M; Dates of Service: 04/2021 – 09/202
The project involved construction of 4 viaducts 280 to 320 feet long, comprising 2 frames and 7 to 9 spans with middle hinges. They are built as 20-foot widening to existing roadway with complicated horizontal and vertical curves. They consist of 20-inch reinforced slabs on grade supported by 24-inch CIDH piles with 4-foot galvanized pin rebar cage at top of piles.
Analyzer’s responsibilities included:
- Inspecting installation of construction area signs and temporary striping and signal light systems, and temporary roadway widening with hot mixed asphalt concrete; layout and construction of CIDH piles, abutments and hinges, bent caps and deck slabs, including rebars and concrete pours; methacrylate deck treatment and installation of waterproofing seal and membrane; installation of polyester joint seal dams; hot mix asphalt concrete paving and fog sealing; installation of concrete barrier and bicycle railing; installation of Type B joint seal; pavement grinding and punch list work; drainage culverts and headwalls.
- Maintaining the CIDH pile logs, recording start, finish and progress of installation in addition to installation problems including depths of water intrusion, location and depth of caving, slurry backfill and re-drill, grout leakage into river, signs of insufficient dewatering causing contamination of concrete with mud sludge.
- Writing diaries, maintaining concrete pour records and documentation for material release tags, and preparing as-built plans.
- Computing finish grades for abutments, hinges, top and bottom of slabs, pile cutoff and top of pin.
- Measuring and recording in as-built plans the types and locations of all rebar couplers in deck slabs and concrete barriers.
Value Added
- The construction of CIDH piles was fraught with difficulties due to hard rock, excessive seepage and caving-in. The seepage and hole stability challenges were mitigated by constructing first the CIDH piles upstream of the seepage path thereby reducing the potential seepage on downstream piles constructed later. Also, the CIDH piles were staggered in construction sequence in order to maximize the distance of between piles constructed in the same shifts, thereby increasing the stability of holes drilled later.
- Because of porous soil conditions due to underlain boulders, rocks and sand, grout leakage into the Yuba River remained a clear and present challenge and grout curtain was installed in the river to mitigate the issue.
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