STRUCTURAL ENGINEERING

Services Include:
(see below for representative projects)

  • Major Highway Bridges
  • Building Renovations
  • Regulatory Agency Grants and Permitting
  • Retaining Walls
  • Box Culverts
  • Single-Span Bridges
RGA provides structural engineering services for transportation projects, park and trail projects and commercial buildings.
Ricardo J.F. Gonçalves, P.E. ​
president
Cell: 303-901-2367
[email protected]

Representative Projects
(Click to Open)

Structural Engineering

Adams County, Colorado
Adams County Bridge 303

​The RGA team designed an 80' single-span bridge, a quarter mile of roadway, channel improvements and a park. The roadway stayed open at all times during construction.
​

​Adams County, Colorado
72nd Avenue Bridge over Burlington Ditch/96th Avenue over O'Brien Canal, Federal Aid Project #C120-015

The RGA team prepared construction plans, specifications, and estimates for the replacement of two single-span bridges. The project included roadway approach design and, for the 72nd Avenue bridge, the design of new roadways to accommodate a relocation of the bridge. Construction phasing of the bridge replacements was complicated by the year-round flow in the irrigation ditches. 

City of Alamosa, Colorado​
Alamosa Pedestrian Bridge

This project required the design of a 300' three-span bridge over the Rio Grande River. This bridge utilized precast box girders and a concrete deck. The abutments and piers were founded on steel piling to protect against river scour. RGA coordinated with the U.S. Army Corps for the 404 Permit and with their levee project in Alamosa. RGA provided construction observation and administration. 

City and County of Boulder, Colorado
U.S. 36 and Baseline Road Bikeway Connector

The RGA team provided the design of approximately 1,000 LF of a concrete bikeway connector along U.S. 36 and Baseline Road in conjunction with highway and ramp widening. Work included profiles, design of an underpass under the on-ramp to U.S. 36, extensive rock retaining walls, storm sewer and irrigation ditch bypass, local drainage and coordination with CDOT Region IV. 

City of Brighton, Colorado
11th Street Culvert Extension and Chambers Road Bridge Replacement over the Fulton Ditch

RGA was part of a design/build team for two structures on 11th Street, adjacent to the Brighton Recreation Center.  On 11th Street, RGA designed a 55-foot extension of an existing 5’x9’ concrete box culvert, as well as a 37-foot single-span bridge on Chambers Road over the Fulton Ditch.  This bridge was considerably wider than the existing bridge to allow for future widening.  RGA also designed 850-feet of new roadway.  This project required coordination and approval of Fulton Ditch Company.

City of Colorado Springs, Colorado
North Gate Boulevard Bridge

RGA provided design and construction management for this design/build project where the construction timeline was controlled by the hibernating Preble’s Jumping Mouse. The bridge is a 126-foot, single-span bridge using BT72 girders and a 103-foot wide concrete deck. The bridge utilizes extensive wingwalls supported on concrete caissons. As North Gate Boulevard is a major arterial street, the bridge was designed for three traffic lanes in each direction, including sidewalks on both sides. The bridge also carries an 18-inch waterline, a 6-inch gas and an 8-inch pumped sanitary sewer line. 

City of Colorado Springs, Colorado
Stetson Hills Boulevard Bridge

Stetson Hills Boulevard is a major arterial street and this structure has two bridges, one westbound and one eastbound.  Each bridge  is a 70-foot, single span bridge utilizing BT42 girders and concrete caisson foundations.  Each deck is 48’ wide, with a sidewalk on the outside edge.  This bridge also carries and 24” waterline and several electrical conduits.

City of Denver, Colorado
56th Avenue Bridge over First Creek

Two 75-foot single-span bridges crossing First Creek south of Denver International Airport. The bridges used precast concrete box girders and a concrete deck.  A deep foundation using drilled piers was required due to possible stream scour.  The bridge carries a 24" high-pressure gas line.  Coordination was required with the City of Denver and several utility companies.

City of Fruita, Colorado
​​Ottley Avenue Bridge

​88-foot single span bridge that crosses Little Salt Wash (Q100= 4340 cfs) in Fruita, Colorado.  The original bridge was load posted and too narrow for the street improvements also designed with this project.  Ottley Avenue is the primary road to several schools in the area.  The Town of Fruita required that the bridge only be out of service during the summer months, while school was out.  RGA devised a plan where the Town purchased the needed prestressed concrete girders, in advance, and provided them to the contractor to help meet this very aggressive schedule.  In addition a portion of the existing substructure was retained to act as bank projection.  This saved money and shortened the demolition time required.  This bridge uses precast box girders that were placed side by side to eliminate the need for deck forms, which again saved time.  The new abutments were supported on steel H-piling.  This overall approach allowed the bridge to be opened to traffic as the new school year began.

City of Grand Junction, Colorado
Colorado River Pedestrian Bridge​

This three-span bridge is 410-feet long and utilizes two G68 pre-stressed girders (per span) and a 12-foot wide concrete deck. At each pier, there is a 6-foot radius observation platform on each side of the walkway. There are lights embedded in the rail posts that illuminate the deck without lighting up the entire river. There are single 54-inch diameter concrete caissons drilled to bedrock at each pier and 24-inch diameter caissons at the abutments. The RGA team received an ACI Award of Commendation for the design of this bridge.

City of Sheridan, Colorado
Irving Street Bridge at Bear Creek

The existing outdated 5' wide bridge and abutments were replaced with a prefabricated 10' wide x 70' long steel truss bridge on new abutments cased on steel piles driven to refusal. New approach slabs on each side transitions the existing tail grade to the new bridge deck and vastly improved accessibility from both ends. This project had the challenge of temporarily relocating three (3) overhead utility lines on each side of the creek before construction could start .This was needed in order for the foundation piles to be driven and setting the steel bridge structure. Power to the adjacent properties had to be continuously supplied during the construction. These temporary relocations delayed the start of construction to the winter months where additional winter concreate precautions were implemented to complete the construction. Project costs were monitored and were below the engineer's total estimated cost while completing the project in a timely manner.

City of Steamboat Springs, Colorado
Pine Street Bridge over Soda Creek, Federal Aid Project No. BRO M2510016

This 50-foot single span bridge was replaced with Federal bridge replacement funds. The design and bid documents were reviewed and approved by CDOT. There was a US Army Corps of Engineers Permit required. The hydraulic analysis led to a bridge layout that did not change the FEMA regulated flood plan and retained some of the existing abutment as bank projection.

City of Steamboat Springs, Colorado
Yahmonite Street Bridge over Soda Creek

This 40-foot single-span bridge was replaced using local funds.  A US Army Corps of Engineers Permit was required, as well as coordination with the State of Colorado Department of Wildlife.  There was an existing 3 foot drop in the channel, downstream of the bridge. The Department of Wildlife requested a series of pools to be installed up to the bridge to allow trout to migrate up and downstream. A new waterline passed through the abutment along with an existing sanitary sewer.

Colorado Department of Transportation
I-76 and 120th Avenue Interchange, State Highway 2 over the BNSF Railway

This is a 213 foot three span bridge over the Burlington Northern, Santa Fe Railroad. This bridge utilized precast concrete BT girders with foundations that utilized steel H-piling.  There was extensive coordination with CDOT and the BNSF Railroad.

Douglas County, Colorado
Parker Ridge Well Facility

RGA designed a single-story concrete block building to house booster pumps, piping, an electrical room, and 80,000 gallon wet well. 

Parker Water and Sanitation District, Parker, Colorado
Lemon Gulch Bridge

​The bridge spanning Lemon Gulch provides private access to a large pump station and water diversion structure. The 220-foot two-span bridge uses BT54 precast concrete girders with steel piping supporting the center pier and abutments. Due to limited traffic, the roadway width on the bridge was reduced to 20 feet. This bridge also carries a 6-inch gas line, an 8-inch water line, and a 27-inch sanitary sewer line.  

Parker Water and Sanitation District, Parker, Colorado
West Interceptor Pedestrian Bridge

​Development on the west side of Cherry Creek created the need for a new 14,000 L.F. interceptor in the southern part of the District's service area. RGA was contracted to design five miles of sewer line varying from 18" to 36" in diameter. RGA also designed a pedestrian bridge that could carry the pipe on the bottom to eliminate the need for a lift station. RGA performed construction management. The alignment was in Prebble's Jumping Mouse habitat and construction was confined to 30' in width. 

South Suburban Park & Recreation District, Centennial, Colorado
​Dutch Creek Pedestrian Bridge

Previous to the design and construction of this bridge, the District bike path, along South Platte Canyon Road, crossed the concrete box culvert shown in the photograph.  When the Platte Canyon Road was to be widened, the bike path was relocated to the adjacent pedestrian bridge.  This is a 95 foot, single span bridge that supported on concrete spread footings. 

South Suburban Park & Recreation District, Centennial, Colorado
Orchard Pedestrian Bridge

RGA designed this 55-foot single-span bridge over the Highline Canal.  This project also included the foundation design and modifications to the Highline Canal Trail, near the bridge.  The bridge allowed additional neighborhoods access to the extensive Highline Canal trail system.

Stonegate Village Metropolitan District, Douglas County, Colorado
​Well Facility Design

Over 20 years, the RGA team designed fourteen (14) well facilities for the district. All of those wells are in the Denver Basin aquifer and included well pump design, structural design, site design, agency approval, and construction management. Throughout the years, maintenance and replacement has been required at most of the facilities, and our firm provided engineering services for these occasions.

Stonegate Village Metropolitan District, Douglas County, Colorado
​Concrete Pedestrian Trails

RGA provided the design and construction management for concrete trails along two (2) major drainageways within this 2,300-acre development.  The improvements included design and construction of two (2) pedestrian underpass structures.

Town of Estes Park, Colorado
2013 Flood Repair Project

This project consisted of 22 separate repair areas. Work included establishing construction easements, survey pins, repairs and replacements for roadways, trails, retaining walls, repairs to asphalt, concrete, bridges, swales, embankments, and slope and bank stabilization. RGA provided design services including survey, geotechnical and environmental reports and evaluations. RGA produced design plans, contract documents, cost estimates, and has advertised, bidding services and full-time construction management for the town. As part of this work, RGA coordinated with the Town of Estes Park, CDOT, FEMA, all utility providers and obtained required clearances and permits. On behalf of the Town, RGA produced temporary construction easements and exhibits and met with affected property owners to explain the project and obtain signatures for the temporary construction easements. RGA assisted the Town with quarterly reports, scope change requests, and documentation for entry into the EMGrantsPro system. In addition, RGA assisted the Town to ensure that all work complied with the Town of Estes Park, CDOT, FHWA and FEMA requirements and regulations.

Town of Pagosa Springs, Colorado
Rumbaugh Creek Bridge Retaining Wall Project

​RGA is assisting the town with the stabilization of Rumbaugh Creek Bridge and its associated retaining wall. 

Town of Parker/Douglas County, Colorado
​​Jordan Road Bridge over Newlin Gulch

The RGA team designed the widening of Jordan Road, including a new 100-foot two-span precast girder bridge over Newlin Gulch. The abutments and piers are supported on steel H-piling to protect the bridge if significant scour were to occur. The new bridge was designed to accommodate channel improvements to Newlin Gulch and provided a safer way to cross Jordan Road.

Town of Red Cliff, Colorado
High Street Bridge Replacement Project

RGA assisted the town with evaluation of the existing High Street bridge to the town's water storage tank. We provided cost estimates for bridge replacement for the town to submit to the Special Highway Committee for funding.