Vasco Safety Improvements - Phase 1

Final Striping Complete--Roadway fully open

2011-11-10T14:47:00.001-08:00

The final pavement stripes were placed on November 9 at the Contra Costa County Vasco Road Safety Improvements project site. This marks the last major item of work on the project. Work will continue at this site through November on clean up work generally off the roadway including fencing, minor drainage, and clean water facilities.

Pictures of the newly striped roadway attached.

Enjoy!

Vasco Road delays- Nov 10 8:30 to 3:00 pm Alameda side

2011-11-09T18:01:00.001-08:00

Vasco Road will be under signal lane controls on the Alameda County project from 8:30am until 3:00pm on Thursday November 10th.

The Contra Costa County project will not have any more lane closures this week.

If you have any questions, please contact Neil Leary at (925) 313-2278

Single Lane Controls - Vasco Road (Nov 9)

2011-11-09T08:44:00.000-08:00

Vasco Road will be under single lane controls on the Alameda County project on Wedsday Nov 9th from 7am to 7pm. The Contra Costa County project will also have single lane controls on Nov 9th from 8:30am until 5pm.

Traffic will be subject to significant delay (up to 40 minutes) on Vasco on November 9th due to the work at both Alameda and Contra Costa County project sites.

If you have any questions please contact Neil Leary at (925) 313-2278.

Single Lane Controls - Vasco Road (Nov 1, 4, 5, and 6)

2011-10-31T16:50:00.000-07:00

Vasco Road will be under single lane controls through the Contra Costa County median barrier project on November 1, 4, and 5. Traffic will be subject to 30 minute delays from 8:30am to 3:00 pm on the weekdays and from 7am until 6pm on the weekend (Nov 5).

Alameda County also is planning work on Vasco Road that will put the road on single lane controls on November 1, 5 and 6. With both projects (Alameda and Contra Costa County) causing delay on November 1 and 5, the travelling public may be subject to up to 1 hour of delay on those days.

The work in Contra Costa County causing the delay is final signing and striping.

The work in Alameda County causing the delay is paving of the roadway.

If you have any questions, please contact Neil Leary of Contra Costa County at (925) 313-2278.

Vasco Road Delays--November 1

2011-10-28T15:51:00.000-07:00

Vasco Road will be subject to 30 minute delays on November 1 from 8:30 am until 3pm due to work on the Alameda County portion of Vasco Road.

The work on the Contra Costa County project to install median barrier and widen the road is nearly complete. Signficant completion of the work is expected by the end of November. The final striping configuration will be installed on November 5th.

Vasco Road delays--Oct 8, 10, 11, and 12; Final Paving date Set

2011-10-07T12:28:00.000-07:00

Vasco Road will be subject to delays the following days:

Saturday October 8-- Contractor to remove k-rail (temporary concrete barrier rail) which is no longer necessary for traffic control since the center median barrier is in place and the K-rail conflicts with the upcoming asphalt paving work. One lane of traffic will be made available to each direction of through traffic throughout this operation but in a temporary location via cones/delineators. Speeds will be reduced to 25 mph through the site and may be stopped at points during day to move construction vehicles in and out.

Monday, October 10--Contractor to prepare existing pavement for asphalt concrete overlay by grinding off areas of existing pavement, construction staking will also be done in preparation for the upcoming paving work; Through public traffic will be under single lane traffic controls--subject to 30 min delay

Tuesday, October 11--Continuation of work from Monday (if necessary)--traffic subject to 30 min delay

Wednesday, October 12-- Contractor to install final lifts of asphalt paving to the western side of the project. This work completes the asphalt paving for this project. Contractor expects to work from sun up to sun down (7am to 7pm) to complete this work. Both directions of public through traffic will be pushed to the east side of the roadway via cones/delineators. Traffic will not be delayed during this paving operation but they will be routed through the area in a new location for duration of the work and subject to 25mph speed limit. Following the paving work both lanes of traffic will be returned to the west side of the road via temporary markers/delineators. Permanent striping will be installed within one week of paving putting traffic in the final, finished configuration--northbound traffic on the east side of the new median barrier and southbound traffic on the west side of the new median barrier.

Single lane controls- Vasco Rd (Alameda) Sept 21-23

2011-09-19T15:47:00.000-07:00

Vasco Road will be under single lane controls between the hours of 8am and 5pm on September 21, 22 and 23. Traffic will be subject to 30 minute delays. The work causing the delays occurs on the Alameda County job, south of the County line on Vasco Road. The contractor will be reconstructing the existing shoulder area directly adjacent to traffic lanes causing the need to shut down an entire lane (only one lane open to handle both directions of traffic). The message boards at either end of the work have been changed to notify road users of this upcoming lane closure and 30 min delay to traffic.

Paving and Barrier installed

2011-09-19T11:31:00.000-07:00

The past 3 weeks have been busy on Vasco Road. As the calendar turned to September, the County's contractor, Teichert Construction, completed the paving operation along the east side of Vasco Road (5 mi south of Camino Diablo). This work marked the footprint of this project's total pavement widening. During this 3-day paving operation (September 1, 6 and 7), Teichert installed approx. 5,600 tons of hot mix ashphalt concrete pavement.

Following the paving operation, Teichert installed the center concrete median barrier for approximately 1 mile in length down the new road centerline. This work was done by a special extrusion machine which moved about 2 feet per second average through the project area. Pictures attached.

Vasco Road Delays

2011-09-19T10:50:00.000-07:00

With the recent start of Alameda County's project to install an approx 1 mile long median barrier on Vasco Road, the route from Livermore to Brentwood on Vasco Road is subject to delay. Contra Costa County will be diligent in informing the road users via the portable message boards of upcoming work causing lane closure and associated delays to traffic. Please note that jurisdiction changes at the County line and work in Alameda is under different management. For any questions on the Contra Costa County portion of the work (or any questions on Vasco), please call Neil Leary (925) 313-2278. (Note: Neil replaces Warren Lai as the County contact). For any questions on the Alameda project, please call inspector Danny Guzman at (510) 670-6606.

There will be significant work on Vasco Road in both Alameda and Contra Costa County over the next two months causing delay to traffic. Contra Costa is committed to notifying road users in advance so that you can make other commute plans if necessary.

Alameda County to begin median barrier project August 22

2011-08-12T16:01:00.000-07:00

Alameda County has issued a notice to proceed to their contractor to begin work on August 22 on a project that includes installation of one mile of a concrete median barrier to be placed along the centerline of Vasco Road from the County line to the Los Vaqueros Reservoir entrance road in Alameda County. Contra Costa County is in contact with Alameda County to coordinate traffic control efforts to minimize the impact to the traveling public along this busy commute corridor. Teichert Construction will be the prime contractor for both the Alameda County project as well as Contra Costa County's safety improvement project to widen the road and install a center median barrier. Having one contractor on both projects will ensure good coordination between projects.

August 17 and 18 single lane controls on Vasco Rd

2011-08-12T15:55:00.000-07:00

On August 17 and 18 Vasco Road will be under single lane controls so that the Contractor, Teichert Construction, can perform crack sealing on the existing asphalt concrete pavement. This work is needed to prolong the life of the existing pavement section and precedes an asphalt concrete overlay scheduled for later in August. Expect up to 20 minutes of delay when traveling on Vasco Road through the project area during these dates.

Project update

2011-08-05T16:02:00.000-07:00

On the night of July 12th, traffic lanes were reset on Vasco Road so that the contractor can begin stage 3 work along the east edge of the road. This move allows the contractor to begin the construction of the new pavement widening along the east edge of the road which includes over 40 feet of pavement widening in areas. After the pavement work is complete later in the month of August, the contractor will begin work on the center concrete median barrier. Project work is nearly 80 percent complete. The project is expected to be complete by December 2011.

August 8 and 9 single lane control on Vasco Road

2011-08-05T15:56:00.000-07:00

Vasco Road will be under single lane traffic controls on August 8 and August 9, 2011 so that the Contractor, Teichert Construction, can install hot mix ashpalt across the roadway. The traveling public should expect up to 20 minutes of delay on these dates.

Traffic Shift July 13th; Single Lane Controls July 6, 7

2011-06-28T16:20:00.000-07:00

Teichert Construction will be shifting the traffic configuration on Vasco Road during the night of July 12th. The work to implement the Stage 3 Traffic Configuration will begin the night of July 12th and possibly carry over into the next night as necessary. The travelling public will see a new traffic configuration on the roadway on July 13th. The message boards situated along Vasco Road will notify Vasco Road traffic of the changes beginning on July 8th.

On July 6th and 7th Vasco Road will be under single lane traffic controls between 8:30 am and 3:30 pm so that project work can be completed. The message boards along Vasco Road will notify the travelling public of these traffic controls beginning on July 1.

Construction Photos

2011-06-13T09:57:00.000-07:00

Construction Season is Here!

2011-06-09T17:42:00.000-07:00

Construction of the Vasco Rd Safety Improvements Project continues into the 14th month. Construction Stages 1 and 2 are now complete with the recent paving work that was installed by Teichert Construction’s paving crews on June 2 and June 3. Stage 3 work, the final work stage, officially begins later this month with the shifting of public traffic onto the new pavement along the west project edge. The shift of traffic will allow for the grading and paving work to begin along the east edge of the project. The shift will also allow for the construction of the center concrete median barrier--the project’s primary feature. The large retaining walls that line the roadway edges are nearly complete with only facing elements left to install. The storm drain and wildlife culvert crossings of Vasco Road are now complete which will reduce the need for signal lane traffic controls. The project is still on track to be completed by December 2011.

Construction Continues

2011-04-07T08:46:00.000-07:00

Teichert Construction continues construction of the Vasco Rd Safety Improvements Project into the 2011 winter season. Stage 1 Improvements (widening of the Brushy Creek Bridge and construction of 6 retaining walls) were completed during the summer 2010. Construction of Stage 2 improvements began in early 2011, consisting of storm drain and wildlife crossing installation and architectural finishing of the retaining walls. Construction activity has been limited to the recent weather, however Teichert Construction continues to make steady progress. The architectural concrete finish (fractured fin) for portions of the southern project limit retaining walls were recently completed in late February 2011 with the remaining walls at the northern limit to be completed by June. As drier spring weather approaches, it is anticipated that significant construction progress can resume. The remaining portions of Stage 2 (grading and paving) will start in early Spring 2011 with Stage 3 improvements (consisting of median barrier and wildlife fencing installation, grading, and paving) scheduled to start in June 2011. Pending weather delays, the project is anticipated to be completed by December 2011.

Stage 2: Working Through Wet Weather

2011-03-16T08:12:00.001-07:00

Teichert Construction continues to proceed with Stage 2 improvements during the recent wet weather. The majority of the construction operations consist of installing storm drain along the roadway in conjunction with wildlife crossings. The wet weather limits the ability for construction equipment to access grading areas near the retaining walls. Prolonged days of thick fog has also limited Teichert Construction's ability to implement lane closures for installation of storm drains across Vasco Rd. As spring approaches, Stage 2 roadwork will commence upon completion of storm drain operations.

In early February, Teichert Construction performed remedial slide repair work at Wall 4 North. This repair operation consisted of excavating a hillside to remove a recently discover slide plane, installing a keyway, and regrading the slope to accommodate the future lane widening.

Excavated storm drain trench at Wall 6.

Forming a storm drain inlet around the recently installed storm drains at Wall 6.

After the recent rains, a weep hole drains subsurface water collected behind Soil Nail Wall 7.

Cast In Place Facing Walls

2010-12-29T11:30:00.000-08:00

Teichert Construction has completed portions of the Cast in Place (CIP) facing walls that will ultimately provide the architectural facing along all the retaining walls on Vasco Rd. Upon completion of the soil nail installation and shotcrete facing walls, a CIP wall is then installed to create the final wall face and grades along the future road shoulder widening. A concrete barrier will be installed at the bottom of the wall, to "mirror" the future median barrier.

Wall 2 CIP facing wall forms.

Wall 2 CIP forms and steel reinforcement.

CIP facing wall and exposed shotcrete, geocomposite drains, and soil nails at Wall 2.

"Fractured Fin" Finish at Wall 2.

Concrete Wall 1

2010-12-29T11:20:00.000-08:00

Teichert Construction completed the foundation for Concrete Wall 1 in November. This relatively small retaining wall is designed to support the the southbound Vasco Rd embankment at the southern limit.

Initial grading at Wall 1.

Extension of reinforcing steel up from Wall 1 footing.

Wall 1 footing.

Completion of Soil Nails

2010-12-29T11:12:00.000-08:00

By mid November, Teichert Construction completed installation of all the soil nails associated with Walls 4, 6, and 7. Over 900 nails were installed in the hillside to secure the slopes to the recently formed shotcrete walls. Nail lengths varied from 15 ft to 60 ft deep into the hillside. A fractured fin texture will become the final finish when the cast in place facing walls are poured next.

Completed soil nails at Wall 6.

Brushy Creek Banks Complete

2010-12-29T11:06:00.000-08:00

At the end of October, Teichert Construction completed backfilling operations around the new Brushy Creek bridge abutments. In conjunction with the final earthwork operations, rock slope protection (RSP) was relocated to shape the banks around the abutments to protect the final slopes from erosion.

Looking upstream along Brushy Creek.

Bedrock Removal at the Retaining Walls

2010-10-31T17:11:00.000-07:00

Teichert Construction has been excavating portions of the hillside to construct Soil Nail Walls 4,6, and 7. Various soil strata are encountered, including significant concretions of cemented sandstone. Construction equipment such as dozers and excavators complete the majority of retaining wall excavation. On occasion, hydraulic breakers are required to crack the hard sandstone rock prior to it's actual removal.

A hydraulic breaker attached to a backhoe prepares to hammering into a sandstone concretion at Soil Nail Wall 6/7.

The completed breaking operation.

Bridge Falsework Removal

2010-10-31T17:01:00.000-07:00

Within the last few weeks, Teichert Construction removed the falsework supporting the recently constructed Brushy Creek bridge. Falsework removal operations consists of safely removing the supporting beams and clamps used to support the wood bridge forms. Cranes and lift equipment slowly secure and pull out the steel beams while the wood forms are stripped from the bottom of the bridge structure. Upon completion of this operation, Teichert Construction will complete the finish grading beneath the bridge and remove the water control system.

Teichert Construction workers begin securing the steel beams supporting the wood forms.

Teichert Construction finishing the final grades at the bridge abutments.

As the falsework beams are removed, the wood forms are stripped away and the concrete finish at the bottom of the bridge is finally exposed.

EXPECT DELAYS: 10/26 to 10/28

2010-10-25T21:57:00.000-07:00

Teichert Construction will be implementing 1 lane traffic control on Tuesday, 10/26 to Thursday, 10/28 from 8:30 am to 3:00 pm.

EXPECT DELAYS: 10/11 to 10/13, 8:30 am to 3:00 pm

2010-10-10T16:15:00.000-07:00

Teichert Construction will be implementing 1 lane traffic control on Monday, 10/11 to Wednesday, 10/13, from 8:30 am to 3:00 pm. This is operation is necessary to safety off haul soil excavation material at the northern project limit (Soil Nail Wall 6/7). Commuters are advised to expect 30 minute delays and take alternate routes during the off peak commute hours.

Southward view of the project site from Soil Nail Wall 6 (completed Brushy Creek bridge widening in the distance).

Bridge Deck Curing

2010-10-02T20:30:00.000-07:00

Teichert Construction completed the intial curing of last week's bridge deck pour this week. This operation was followed by tensioning of the bridge itself. Steel tendons were installed in longitudinal ducts within the bridge structure. Once these tendons were secured and anchored at one end of the bridge, a load was applied from the other side of the bridge to tension the structure. After jacking to the required load, the force in the tendon is transfered from the jack to the end of the anchorage. Prior to it's release from the jack, the tendon is secured by wedges and then the protruding tendon strands can be cut off. This post tensioning operation minimizes the stresses on the bridge from it's own concrete load and eliminates potential cracking to produce a more durable concrete bridge.

The bridge deck is finally exposed after curing under wet burleen blankets for a week.

A hydraulic ram jack is placed over a steel tendon prior to tensioning.

Teichert Construction cuts the protruding tendon strands after completion of tensioning operations.

Soil Nail Wall 7 Operations

2010-10-02T20:09:00.000-07:00

After excavating for the first lift of soil nails for Wall 7, Teichert Construction began the process of installing soil nails, steel reinforcement, and shotcrete to form the structural wall itself. This sequencing of work typically takes at least a week from start to finish (excavation, drilling, nail installation and grouting, steel reinforcement, and then shotcrete). County Inspection staff perform onsite inspection of the complete operation to ensure that the proper design specifications are achieved. Inspectors are responsible to verify that the contractor excavates the hillside to the surveyed limits, confirm that soil nails are installed and grouted to the designed lengths, and ensure that the proper reinforcing steel is placed and shotcrete is applied properly.

After excavation, soil nails (40 to 50 ft in length) are installed.

Geocomposite drains ("black strips") are evenly spaced along the cut face.

Prior to shotcrete facing, reinforcing steel mesh and rebar are installed.

An initial layer of shotcrete is applied to the prepared wall face.

Shotcrete is uniformed applied until the design thickness is achieved.

Brushy Creek Bridge Deck Pour

2010-09-27T18:20:00.000-07:00

Last week, Teichert Construction completed the deck pour of the Brushy Creek bridge, a milestone event. The concrete deck pour took place at 4 am to minimize the affects of the wind and heat on the concrete itself. Conducting the deck pour prior to the morning commute hours also minimizes the travel time for concrete trucks transporting the material from the plant to the project site. Prior to the deck pour itself, a bidwell was installed on temporary railings supported by the deck forms. Traveling above the deck on rails, the bidwell evenly spreads the concrete (pumped onto the deck in separate operation) to create the final road surface. The temporary rail system and bidwell ensure that the final deck grades are constructed to the designed road grades.

Teichert Construction spreads the concrete prior to the bidwell screeding the concrete to the deck grade

The bidwell passes over the concrete. The auger in the front collects and spreads the concrete while the roller and finish pads ensure the correct grade is formed.

Concrete is pumped directly onto the deck in advance of the bidwell.

After the bidwell passes over the concrete, finishers spray curing compound from a catwalk.

County Inspection Staff test the concrete material properties onsite to ensure quality assurance.

Soil Nail Wall 7 Excavation

2010-09-27T18:02:00.000-07:00

Teichert Construction began excavation operations last week for Soil Nail Wall 7, located at the northern project limit. The existing hillside excavation consists of removing occasional sandstone and cemented rock formations. In addition to excavators and blade equipment, Teichert Construction is using breakers to chip and remove the bedrock material. After each "lift" is excavated, soil nails are installed to secure the hillside followed by the shotcrete wall facing.

Teichert Construction excavates the hillside for the initial wall lift.

Exposed rock within the soil strata along the hillside cut face.

Teichert Construction uses a breaker to remove sandstone along the cut face.

Installed soil nails along Soil Nail Wall 7.

Soldier Pile Wall Work Continues

2010-09-20T21:14:00.001-07:00

Teichert Construction has completed a signifcant portion of the soldier pile retaining walls required for the road widening at the southern project limit. Steel piles were installed and cast in concrete holes along the hillside. Teichert Construction crews then excavated the hillside and installed timber lagging to retain the hillside slope. A concrete facing wall be installed in front of the timber wall with an architectural finish in the following months.

Teichert Construction removes "lean" concrete and soil around the piles to install timber lagging.

Southbound view of the Soil Nail Wall 2.

Bridge Work Continues

2010-09-20T21:02:00.000-07:00

In the last month, Teichert Construction has made significant process in completing the construction of the Brushy Creek bridge widening. Wood form work for the bridge structure was erected and steel reinforcing bars installed. The "stems and soffit" of the bridge structure was poured with only the main deck pour remaining.

Teichert Construction erects forms for the "stems" that come up from the bottom of the bridge (soffit).

Reinforcing steel bars and installed for the stem and soffit.

Northbound view of the bridge widening.

Completion of concrete "stem & soffit" pour.

Soil Nail Wall 4 Production Nail Installation Begins

2010-08-23T09:18:00.001-07:00

After completion of verification nail testing and waiting for the proper soil nail materials to be delivered, Teichert Construction began installation of production nails at the Soil Nail Wall 4. The results of verification nail testing confirmed the appropriate soil nail lengths as well as allowed for a redesign of the nail layout for ease of construction. Six inch diameter holes are drilled into the hillside to design lengths prior to installation of the actual steel nail. Grouting of the nail must take place immediately after drilling to prevent cave-ins. Wire mesh and steel reinforcement are then installed along the soil cut face prior to the installation of the shotcrete wall facing.

Installed soil nails along with the Soil Nail Wall 4 cut face extend outward. The black geocomposite drain strips are installed against the soil and will be extended down as each soil nail lift is excavated.

Reinforcing steel bars extend above the cut face to eventually support the extension of a concrete cantilever wall.

Shotcrete installation operation at Soil Nail Wall 4.

A soil nail extends through the reinforcing steel, wire mesh, and initial layer of shotcrete.

Soldier Pile Wall 2 Work Begins

2010-08-23T09:06:00.000-07:00

Teichert Construction began construction of Soldier Pile Wall 2 at the southern project limit. Besides the use of soil nails to secure the hillside along Vasco Rd, soldier pile wall retaining systems will be used to stabilize the minor hillside cuts. Approximately 20 to 30 ft deep holes are drilled to accommodate concrete cast in place steel piles. Timber lagging will be installed in between the steel piles prior to the final concrete facing wall. Upon completion Soldier Pile Wall 2 will be approximately 12 ft tall at the highest location.

Drilling rig staged at Soldier Pile Wall 2 location.

Drilling down to pile tip elevation.

Steel pile secured in the proper location prior to concrete pour.

Brushy Creek Bridge Abutments Complete

2010-08-23T08:54:00.000-07:00

Teichert Construction completed the Brushy Creek Bridge abutments by pouring them in early August. The abutments secure the bridge structure itself to the footing foundation. Steel reinforcement extends from the footing up into the abutment, which will eventually connect to the bridge deck.

View of Abutment 1.

Falsework installation at Abutment 2.

Laying out falsework girders at Abutment 1.

Brushy Creek Bridge Abutment Work Begins

2010-07-17T10:00:00.000-07:00

Earlier this past week, Teichert Construction completed the Brushy Creek Bridge concrete footing pour. Upon completion of this operation, construction workers stripped the wooden forms to expose the concrete footing and began erecting the abutment forms. As this operation proceeds, one can visualize the bridge structure itself as the foundation begins to come up. Reinforcing steel (vertical bars) were installed in the footing to extend up into the abutments to secure the bridge to the footing foundation.

Stripping the footing forms at Abutment 2.

View of Abutment 2 footing (foreground) with Abutment 1 forms in the distance.

Abutment 1 forms being erected.

Brushy Creek Bridge Footing Pour

2010-07-17T09:46:00.000-07:00

This past week Teichert Construction completed their first major concrete operation, Brushy Creek Bridge footing pour. A concrete pumping truck set up between the two bridge abutment footings while concrete trucks lined up to supply the materials. County Inspection staff monitored the pour itself while County Materials Testing laboratory staff verified the material quality and obtained samples for further quality assurance sampling.

Concrete being pumped into the Abutment 1 footing form.

Concrete at the Abutment 1 footing, lowest step.

County Materials Testing Laboratory Staff obtaining concrete samples onsite for quality assurance compressive strength testing.

Bridge Footings and Shotcrete Test Panels

2010-07-10T13:38:00.000-07:00

This past week Teichert Construction began forming the bridge footings and installing the rebar in anticipation for a concrete pour next week. The recently driven piles are anchored to the footing via rebar which also extend up into the bridge abutments. Pre production soil nail wall work continued this pass week with additional verification nail testing and pre construction shotcrete test panels. Upon installation of production soil nails, shotcrete will be used to in conjunction with wire mesh and reinforcing steel to form the retaining wall face itself. This will maintain the wall face integrity while the soil nails stabilize the hillside behind the retaining wall. Test panels of shotcrete are built by Teichert Construction prior to actual wall construction for Construction Inspection to verify the quality of shotcrete workmanship and confirm its strength properties prior to production.

Concrete forms and rebar at the Abutment 1 stepped footing.

Concrete forms and rebar at the Abutment 2 footing.

Construction of a shotcrete test panel (with reinforcing steel).

Pre production shotcrete at a verification nail face.

Pile Driving and Verification Nails

2010-07-05T11:11:00.000-07:00

This past week Teichert Construction completed pile driving installation for the abutment foundation at Brushy Creek. Forty-five to 60 ft long steel H-beams were driven into the soil beneath the abutment footing to provide a secure and stable foundation for the bridge widening. The piles are struck by a pile hammer with sufficient energy to drive the steel through the surrounding creek alluvium and deep into bedrock. Observation of the pile driving operations by County Inspection confirmed the existence of a hard sandstone layer (at shallow depths at the northern abutment) within the foundation's geological layer. This rock stratification provides a good substrate for the piles to secure the bridge footing and abutment. Other construction operations last week included the completion of exploratory drilling for the soil nail retaining walls at the northern and southern project limits. Verification nails were installed to confirm County Design's soil assumptions for the retaining walls. Soil nail retaining wall systems will be constructed as part of the Vasco Rd Safety Improvements project. "Soil nails" of various lengths are installed in bored holes along the hillside. The nails are then grouted in place with high strength concrete. As a complete system, the friction created between the grouted nails and existing soils secure the hillside and prevent slides from occurring. The current verification nail process consists of installing test nails at various locations to identify current soil conditions and quantifying the load the designed soil nails can sustain. Upon completion of this verification process, the "production" nails can be re-designed (shortened) to reduce costs if the existing soil conditions are better than originally anticipated.

Teichert Construction pile driving rig setting up at the southern abutment.

Pile driving at the southern abutment.

Piles driven (at the northern abutment) into the existing sandstone layer, which encountered competent bedrock at shallower depths than expected.

Teichert Construction drill rig beginning to bore for a verification soil nail.

Inclinometers and Bridge Foundation Work Begins

2010-06-26T13:31:00.000-07:00

This week Teichert Construction started to access the hillside north of Brushy Creek bridge to prepare for installation of 2 retaining wall structures. Part of this preparation work is exploratory drilling and inclinometer installation. Exploratory drilling in the hillside is necessary for County engineers to confirm the existing hillside soil conditions and make any necessary modifications to the retaining wall design prior to actual installation. Inclinometers are plastic casings (90 ft in depth) installed on the hillside that are located behind the retaining wall location that measure any hillside movement. Measuring any "hillside" creep is necessary as part of the overall installation process to ensure that retaining wall construction isn't affecting slope stability and as well as providing long term maintenance monitoring. Progress continues with the Brushy Creek bridge widening effort as Teichert Construction crews excavated for foundation footings at the south abutment. This operation will be followed with pile driving, anticipated to begin next week (6/28/10).

Looking north at an inclinometer location. Note, the portion of the hillside, leftside in the picture (down slope) will be excavated for the retaining wall itself.

Inclinometer casing.

Teichert Construction crew excavating the footing for the southern abutment.

EXPECT DELAYS: 6/24

2010-06-21T19:18:00.000-07:00

Teichert Construction will be implementing 1 lane traffic control along Vasco Rd (at Brushy Creek bridge) on Thursday, 6/24/10, from 9 am to 3 pm. Commuters should expect delays while County biologists work on the bridge to re attach netting to prevent birds from nesting on the bridge structure itself. Surprisingly, the concrete angle points on bridges are prime habitat for birds to form "mud" nests. Birds that form new homes on the bridge may delay the project so County biologists monitor and implement measures to prevent birds from establishing nests. On Brushy Creek bridge, netting is installed under the bridge at the abutments and along the edge of deck. Due to the high winds, netting must be constantly maintained and reattached to prevent it from blowing onto the roadway itself or falling into the creek, which is sensitive habitat.

Netting installed under Brushy Creek bridge at the angle point created by the existing abutment and superstructure.

Brushy Creek Bridge Demolition

2010-06-19T20:48:00.001-07:00

Teichert Construction crews completed the majority of the Brushy Creek Bridge demolition this week. The demolition operations were limited to the existing barrier rail on the bridge along northbound Brushy Creek Bridge. A minimal portion of the existing deck was removed so the final concrete pour (closure pour) will transition the existing bridge deck to the new bridge grades. Portions of the exposed rebar on the existing bridge will connect to rebar/concrete in portions of the new bridge widening.

View of the existing bridge with the northbound barrier rail removed and exposed rebar.

County Construction Inspection reviews the operation to confirm the limits of demolition and ensure that the existing structure remains undamaged.

Getting Ready for Bridge Demolition

2010-06-16T19:51:00.001-07:00

One of the Stage 1 construction improvements is the Brushy Creek Bridge widening. Dewatering of Brushy Creek was just the first step in preparing the area for the actual bridge construction. The next step is preparing access to the future bridge foundations, establishing a work area in the dewatered creek, and demolishing the existing bridge barrier rail. Teichert Construction began these initial operations earlier this week by adding metal plates over the creek to protect the bypass pipe from construction equipment and demolition debris. A breaker on the back of a backhoe will do most of the demolition work later this week.

A backhoe with a breaker stages on the work side of the k-rail.

Since the k-rail will prevent vehicles from entering the work area where the existing edge of bridge deck (barrier rail) will be demolished, it must be doweled into the existing bridge deck to prevent movement from collisions with vehicles that may have gone astray.

Looking down from the barrier rail (to be demolished), Teichert has established a work area for future falsework and pile driving operatons while protecting the dewatering pipe from construction equipment and demolition debris.

Stage 1 Traffic Handling Plan Complete

2010-06-11T13:15:00.000-07:00

Teichert Construction completed implementation of the Stage 1 Traffic Handling Plan this week. This plan consists of removing existing rumble strips, traffic striping, and installing temporary concrete barriers (k-rail) along the roadway to establish a safe work zone away from vehicle traffic. A significant portion of this work took place at the northern project limit to accommodate the future Brushy Creek Bridge widening work and Soil Nail wall operations.

Looking Northbound along Vasco Rd at the northern project area.

The established work area behind the k-rail for the Brushy Creek Bridge widening work.

Water Control of Brushy Creek

2010-06-10T20:14:00.000-07:00

Teichert Construction began implementing their water control plan in the Brushy Creek Bridge widening area. Water control or dewatering of Brushy Creek consists of establishing a "dry" work zone in the creek in advance of actual bridge widening construction. The water control plan (also referred to as dewatering plan) consists of installing a silt filter barrier at the downstream work limits and upstream cofferdams. The existing creek flow is diverted through a plastic pipe so clean upstream water bypasses the work area and is discharged downstream of the work area. The silt filter barrier at the downstream end ensures that any work zone runoff is treated prior to flowing downstream of the work area. Initial water quality sampling that compares upstream and downstream water quality during this dewatering operation indicates that none of the operations have adversely impacted the creek water quality. County Construction Inspection provide biological monitoring to identify and manage wildlife encountered during creek work since California red-legged frogs have been sighted this last week.

While creating access to the creek, an excavator makes repairs to the ESA-silt Fence. Maintaining the fence along the project limits is vital in preventing animals from entering the work zone and being harmed as well as treating storm water runoff that may enter the creek.

Looking downstream (from the upstream cofferdam area), Teichert Construction begins to secure the dewatering bypass pipe with existing river rock.

EXPECT DELAYS: 6/7 to 6/9

2010-06-05T22:42:00.000-07:00

Teichert Construction will be doing roadwork along Vasco Rd on Monday, 6/7, to Wednesday, 6/9. Advance notice was given to commuters this past Friday, 6/4, by portable changeable message boards that are along the Vasco Rd. The anticipated construction work hours in the roadways are from 8:30 am to 3:00 pm. The purpose of this work (anticipated to take 3 days) is to continue the installation the Stage 1 traffic control. Teichert Construction removed the existing rumble strips and striping this past Friday (6/7). Construction operations in the road this upcoming week will be focused on installing the k rail (temporary concrete barriers) for Stage 1 traffic control. Upon completion this stage's traffic control, the majority of construction activity can take place behind the temporary k-rail, 2 lanes Vasco Rd traffic will be routed through the work zone, and construction impacts to Vasco Rd commuters will be minimized.

Miles of Fencing!

2010-06-05T21:44:00.000-07:00

Since the Vasco Road Safety Improvements Project-Phase 1 project limits are within a sensitive animal migration corridor, the project has detailed fencing requirements to protect wildlife and ensure their safe access from one side of the road to the other. Installation of 5 miles of temporary wildlife exclusion fencing around the work perimeter is the first order of work to prevent animals from entering the job site. No significant road work, grading, or accessing of Brushy Creek (for the bridge widening work) can occur until all the temporary wildlife exclusion fence is installed. Some of the animals that the fence is designed to protect are the San Joaquin Kit Fox and California Tiger Salamander. The 24" high, black plastic mesh fence also protects construction workers from snakes that may enter work area overnight and hider under stockpiled materials. Construction workers have encountered (almost on a daily basis) rattlesnakes (along with gopher and king snakes) while installing this fence.

Temporary wildlife exclusion fencing along hillside north of Brushy Creek bridge.

Temporary wildlife exclusion fencing at the staging area.

EXPECT TRAFFIC DELAYS: 6/1 to 6/4

2010-05-30T18:55:00.000-07:00

Teichert Construction will be doing roadwork along Vasco Rd starting Tuesday, 6/1 to Friday, 6/4. Advance notice was given to commuters this past Thursday, 5/27, by portable changeable message boards that are along the Vasco Rd. The anticipated construction work hours in the roadways are from 8:30 am to 3:00 pm. The purpose of this work (anticipated to take 4 days) is to install the Stage 1 traffic control. This consists of removing some of the existing striping and channelizers, installing temporary striping, and placing k-rail (temporary concrete barriers). Upon completion of Stage 1 traffic control, the majority of construction activity can take place behind the temporary k-rail, 2 lanes Vasco Rd traffic will be routed through the work zone, and construction impacts to Vasco Rd commuters will be minimized.

Groundbreaking!

2010-05-25T23:05:00.000-07:00

The Vasco Rd Safety Improvements Project - Phase 1 groundbreaking ceremony took place on Monday, May 24, 2010. Check out the local reports.

http://cbs5.com/local/vasco.road.safety.2.1712198.html

http://www.nbcbayarea.com/traffic/transit/Vasco-Road-Improvements-Under-Way-94781624.html