The Vasco Rd Safety Improvements Project - Phase 1 is designed to improve the safety of approximately 1 mile of Vasco Rd between the cities of Brentwood and Livermore. This stretch of twisting Vasco Rd has heavy, fast moving traffic and a history of serious injury accidents. The project consists of installing a concrete median barrier along the 1 mile project limits and widening the southbound pavement to provide a truck climbing lane, thereby eliminating the gap in the existing truck climbing lanes along Vasco Rd. To accommodate these safety improvements, 6 retaining walls, storm drains, wildlife crossings, and a bridge widening will be constructed. This project is anticipated to take 1.5 yrs (2 construction seasons) to complete, anticipated in December 2011. Check out this blog from time to time to see updates on construction progress and facts about the project.

Sunday, October 31, 2010

Bedrock Removal at the Retaining Walls

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

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.

Monday, October 25, 2010

EXPECT DELAYS: 10/26 to 10/28

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.

Sunday, October 10, 2010

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

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).

Saturday, October 2, 2010

Bridge Deck Curing

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

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.