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.

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.

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).

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.

Brushy Creek Bridge Deck Pour

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

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

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

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.