Bridge & Infrastructure Scanning in Pinole, CA

Pinole owns a genuinely difficult bridge. The San Pablo Avenue bridge north of downtown is a thirteen-span reinforced concrete slab structure built in 1938 that carries the city's main street over the railroad, was rated structurally deficient in 2018 with a sufficiency rating of 33.5, and is now the subject of a replacement in the range of seventeen million dollars funded principally by the Caltrans Highway Bridge Program with Contra Costa Transportation Authority Measure J money alongside it. That single structure has every condition that makes bridge survey hard: multiple short spans, a live rail corridor underneath, an operating arterial on top, and a bent-and-abutment layout nobody has measured completely since the drawings were inked. Add the Interstate 80 structures at Appian Way and Pinole Valley Road, the crossings that carry streets and the Pinole Creek Trail over Pinole Creek, and the city's inventory is small but demanding.

Scanning is the right tool where the closure window is the constraint. We observe a control network with GNSS and total station, adjust it by least squares on NAD83 State Plane and NAVD88 with independent check observations, and register each Trimble scan position into it with residuals reported. From setups on the shoulder, beneath the structure, or alongside the right-of-way, millions of survey-grade points per position record deck, soffit, girders and slab underside, bents, columns, abutments, bearings, and joints. Vertical and horizontal clearance is then computed across the whole travelled way or the whole rail envelope from the surface itself, so the controlling low point is located rather than sampled. Anything the designer thinks of later comes out of the archived cloud instead of a second flagging operation.

Deliverables include registered E57 or RCP clouds, DWG or DXF plans, elevations, and soffit contours, clearance envelope reports on a stated datum, and epoch differences for settlement. See infrastructure scanning, Pinole 3D scanning, and deformation monitoring.