(209) 249-4700info@confabca.com

Term Archives: All

Home » All

Green Valley Road OC

By:confab

The longest single piece precast prestressed concrete bridge girders manufactured in California were installed during a warm August 2015 night for the construction of the Green Valley Road Overcrossing structure in Cordelia, California.  The girder shape chosen during type selection for this bridge was the relatively new California Wide Flange which was adopted by Caltrans as a standard section in 2012.  For the Green Valley Road structure, Con-Fab California Corporation fabricated girders that were 7’-6” deep x 166’-5” long, weighing 217,000 lbs each.

Contemporary highway bridge designs are incorporating longer spans which are supported by ongoing advances in concrete and reinforcing technologies.  The CA Wide Flange section was specifically developed to meet the demand for designs with longer clear spans and wider girder spacings for precast bridge structures that are cost competitive with cast-in-place box girder construction. The use of the California Wide Flange Girder in California highway bridge construction has increased demonstrably each year since its adoption by the State which reflects favorably on the cost effectiveness of this section.

While the materials science and fabrication processes are in place to supply this cost effective bridge element, a very important consideration for the use of long precast girders is the identification of any transportation constraints. Extremely long bridge girders can be delivered to most destinations around the State.  However the more remote sites do require a transportation route analysis to confirm the product can be delivered.  California bridge girder manufacturer’s welcome all information requests from designers regarding the ability to deliver long girders to specific sites.

The Green Valley Road Overcrossing structure is a part of a multi-year, multi-phase transportation project conducted by Caltrans, The Solano Transportation Authority, and the Metropolitan Transportation Commission to provide major improvements to the Interstate 80, Interstate 680 and State Route 12 interchanges. The project will benefit citizens by improving travel times, reducing cut-through traffic on local streets, and enhance safety by streamlining connections for motorists transitioning between these three major state routes linking the Bay Area, the Napa Valley, and Sacramento.

 

Project Name:  Green Valley Road OC

Location: Cordelia, California

Owner: The State Of California and the Solano Transportation Authority

Engineer: Mark Thomas and Company, Inc + Nolte Associates

Prime Contractor:  DeSilva Gates Construction

Bridge Subcontractor:  Viking Construction

Precast Subcontractor:  Con-Fab California Corporation

American River College Parking Structure

By:confab

The American River College Parking Structure is an award winning design-build hybrid parking structure produced for a client who placed a high importance on the structure’s look and design. Taking full advantage of the collaborative nature of design-build delivery, the Project Team was able to quickly provide accurate design, constructability, cost, and schedule analyses for numerous options and alternatives to the client prior to submitting the completed contract document package for DSA review.

The completed structure is a 5-level, 486,000 square foot college parking complex with 1,735 vehicle parking stalls and serves as a gateway structure at the campuses main entrance. It utilizes 106 single section, 60 foot tall, precast concrete columns, 314 long span beams and 24 transfer girders combined with post-tensioned cast-in-place concrete decks.  Con-Fab also furnished structural precast bridge slab members for the gateway pedestrian overcrossing and folded plate stair sections for an external signature stairway.

A high priority was placed of the use of sustainable and durable materials for this project.  A low impact landscape design responds to campus standards for sustainability and low water use. The design also includes an allowance for the future installation of 49,400 square feet of roof mounted photovoltaic panels.

From the start of site preparation in May 2012 to project handover in February 2013, this project was completed in 10 months. Precast production commenced while the site was being prepared and the foundations constructed.  The resulting overlap of on-site and off-site construction activities accelerated the construction schedule. Con-Fab erected the complete beam and column gravity frame in 20 working days.

 

Project Name:  American River College Parking Structure

Location: Sacramento, California

Owner: Los Rios Community College District

Architect/Engineer: Watry Design, Inc.

Prime Contractor: Webcor Builders

Precast Subcontractor: Con-Fab California Corporation

Kaiser Parking Structure

By:confab

Project name:             Kaiser Parking Structure #2

Location:                     Oakland

Owner:                        Kaiser Permanente

Architect:                    Walker Parking Consultants

Engineer:                     Walker Parking Consultants

General Contractor:    Overaa Construction

Precaster:                    Con-Fab California Corporation

Completion:                2011

To provide parking to Kaiser Permanentes new facilities near downtown Oakland a new parking structure was needed.

This 1,220 stall structure has 10-levels, of which two are below grade, was constructed using a precast hybrid structural frame of precast columns, beams and girders and cast in place decks and shearwalls.

Con-Fab California Corporation pretensioined the precast columns for handling as they were a single piece and up to 110ft long. The columns were successfully trucked to the jobsite through downtown Oakland. To reduce the height of the building and minimize the ramp slope, the structural depth of post-tensioned deck and beam was 30” with a typical 18ft bay spacing. Con-Fab developed a unique cost effective I-beam spanning 60ft that was able to achieve this constraint and save several feet of shearwall and cladding.

The basement excavation and massive 7,000 yd³ mat foundation, poured in a single operation, was constructed at the same time as the precast was fabricated off site thereby saving significant construction time. This design and build contract is another example of the speed and structural advantages that precast can bring to projects.

Building CA 3E

By:confab

The shell construction of Building CA 3E at Lam Research Corporation’s Fremont, California campus is nearing completion for delivery to the owner in April 2016.  This unique structure supports Lam Research’s core business as an innovative supplier of wafer fabrication equipment and services for the global semiconductor industry.

Thirty 8 inch thick precast prestressed concrete wall panels, measuring 12 feet wide by up to 50 ft tall, were used to enclose two elevations of the structure.  In their final position, these non-load bearing wall panels are laterally supported at three points: at the foundation; at the mezzanine level located 18 ft above the base; and at the fan deck located 49 ft above the ground. The utilization of prestressing accommodates a building geometry that requires the panels to span 31 ft from the mezzanine to the top of panel in a high seismic region.  The performance demand was further elevated by a project specific seismic design criterion specifying an importance factor of 1.5, thereby increasing the seismic design loads by 50% when compared to an ordinary structure.  The inherent benefits of prestressing the panels also simplified the shipping and handling operations.

This project was built on an existing, operating campus with significant limitations to the space available for the contractor’s use.  The construction zone was not significantly larger than the footprint of the new building.  Offsite production of the wall panels allowed fabrication concurrent with jobsite construction activities and mitigated adverse impacts to the construction sequence, schedule and space that would have occurred with site cast walls, providing yet another example of the benefits associated with precast building elements.

 

Project Name:  Building CA 3E

Location: Fremont, California

Owner: Lam Research Corporation

Architect: Devcon Construction, Inc.

Engineer:  Biggs Cardoza Associates, Inc.

Prime Contractor: Devcon Construction, Inc.

Precast Subcontractor: Con-Fab California Corporation

FEATHER RIVER BRIDGE

By:confab

Spliced precast prestressed concrete girder construction has been used to construct the new 16 span, 3,148 foot long bridge structure for the Highway 99 crossing of the Feather River, about 25 miles north of Sacramento, CA.  The new bridge is constructed along the east side of the existing structure and will carry two lanes for northbound traffic.  The existing structure, having previously serviced traffic in both directions, will be used solely for southbound traffic. This $56.2 million dollar project, improving traffic operations and safety, completes the final four-lane highway link between Sacramento and Yuba City, CA. By widening the highway, the region will be able to meet growing traffic demands in the future and lessen congestion during peak travel hours.

Con-Fab California Corporation fabricated and installed 132 girder segments ranging from 49 to 111 feet in length.  The segments were installed in two mobilizations that occurred during the spring and summer of 2013.  The unique precast section utilized by the Caltrans designers is an 8’-6” deep bulb tee and is a modification of the standard California bulb tee section.  Thirteen of the structure’s eighteen spans measure 210 feet which is among the longest precast girder spans ever constructed in California.  In addition to the pretensioned strands reinforcing each segment, multi-strand post-tensioning is used with two-stage stressing to provide continuity within each of the structure’s four frames.

The use of precast concrete girder construction helped mitigate several important site constraints.  The bridges’ location, completely within the drainage limits of the Feather River, limited construction access to the site to about six months of the year.  Precast concrete construction permitted a significant amount of work to be performed off-site and concurrent with on-site activities resulting in an accelerated schedule for completion.  The use of precast concrete also offered a significant reduction of construction activity impact on the site which is an environmentally sensitive area that is critical to the health of numerous wildlife species in the region.

 

Project Name:   Feather River Bridge No. 18-0025

Location:   Highway 99 in Sutter County near Nicolaus, CA

Owner:   State Of California

Engineer/Architect:   Caltrans

Prime Contractor:   MCM Construction Inc.

Precast Subcontractor:   Con-Fab California Corporation

 

Project Detail

Job Name FEATHER RIVER BRIDGE
Job Location HWY 99 OVER THE FEATHER RIVER NEAR NICOLAUS, CA
Date of Completion 2013

Narrative

Interesting Facts, Uniqueness,

Special features, Notable design, Record erection time, Modifications etc.

 THE FEATHER RIVER BRIDGE WAS CONSTRUCTED TO PROVIDE A SEPARATE BRIDGE OVER THE FEATHER RIVER FOR NORTHBOUND HIGHWAY 99 NEAR YUBA CITY.

 

THE ORIGINAL CONTRACTOR WAS NOT ABLE TO COMPLETE THE PROJECT SO MCM CONSTRUCTION TOOK OVER THE PROJECT IN EARLY 2013. ON AN EXTREMELY ACCELERATED SCHEDULE MCM WAS ABLE TO CONSTRUCT THE MAIN STRUCTURAL PORTION OF THE BRIDGE IN ONE SEASON.

 

GIRDER ERECTION WAS DONE AT NIGHT WITH THE TRUCKS DELIVERING THE GIRDERS BEING OFFLOADED AT NIGHT FROM THE EXISTING BRIDGE WHILE MAINTAINING TRAFFIC.

 

FRAMES 2 AND 3 OVER THE FEATHER RIVER HAD TO BE ERECTED WITH THE CRANES ON A TEMPORARY TRESTLE BRIDGE.

Picture Requirements

In Production PROVIDED
Erection PROVIDED WITH AERIAL PHOTOS
Completed REQUIRED

Bridges

Time to erect Stage 1: Frames 3 and 4: MAY 2013: 9 DAYS

Stage 2: Frames 1 and 2: SEPT 2013: 12 DAYS
Number of Girders 132
Type of Girders Caltrans Bulb tee
Length of Girders 111’
Depth of Girders 8’-6”
Weight of each Girder Typical: 168,000#

Maximum: 173,000#

 

Awards

Name and details None

 

Articles

Name and details None

 

HAZEL AVENUE BRIDGE WIDENING

By:confab

Project Detail

Job Name HAZEL AVENUE BRIDGE WIDENING
Job Location SACRAMENTO, CA
Date of Completion JUNE 2010

Narrative

Interesting Facts, Uniqueness,

Special features, Notable design, Record erection time, Modifications etc.

 THIS BRIDGE IS THE WIDENING OF AN EXISTING CAST IN PLACE BRIDGE FOR HAZEL AVENUE OVER THE AMERICAN RIVER. ORIGINALLY THE DESIGNERS HAD PRECAST PANELS WITH A RIPPLE MOTIEF HUNG ALONG THE EDGE OF THE NEW WIDENING BUT CON-FAB VALUE ENGINEERED THE MOTIEF TO BE CAST INTO THE SIDE OF THE FACE OF THE EXTERIOR GIRDER WITH GREAT SUCCESS

Picture Requirements

In Production INCLUDED
Erection INCLUDED
Completed REQUIRED

 Bridges

Time to erect Two weekend days
Number of Girders 16
Type of Girders Caltrans Bulb tee
Length of Girders Max 121ft
Type of bridge Spliced girder
Depth of Girders 84.625”
Weight of Girders 173,000#

 Awards

Name and details None

Articles

Name and details None