| I-10: St. Mary's to 29th |
NCS performed the geotechnical investigations and design for this section of the I-10 widening project under subcontract to HDR. The complete reconstruction of mainline I-10 will include 6 new bridges, 17 retaining walls totaling nearly 14,000 linear feet of walls, drainage structures paralleling the corridor, and pavement design. The field investigation program conducted by NCS included 122 borings for the various structures. A combination of drill rigs was required, including conventional truck mounted, track mounted for drilling on slopes, and difficult access rigs for the sides of steep embankment slopes.
Photo Credits: Some photos during the construction phase are courtesy of ADOT, in particular Antonio Conte. Several others are courtesy of Ted Buell with HDR, Inc. |
| Anthem MSE Wall Repair |
In November of 2004 a semi lost control and hit an MSE retaining wall forming the abutment of the Anthem Rd. TI with I-17. NCS designed the repair of the MSE wall using the soil nailing technique. |
| SR 89a: Banjo Bill Rockfall Containment |
The SR89a: Banjo Bill project was a rockfall containment project involving an anchored micropile retaining wall to generate space to allow for rockfall to fill into a basin without spilling onto the roadway. The project was truly unique and involved micropiles, tiebacks or ground anchors, soil nailing, gabions, inclinometers, piezometers and more.
Photo Credits: Some of the photos on this page are courtesy of ADOT (Jim Monnett / Ed Hall / Richard Solano). |
| Guthrie Bridge |
NCS was retained by ADOT to perform an independent technical review of the geotechnical design of a new Guthrie Bridge that takes US 191 over the Gila River. Also in our scope was the preparation of an axial and lateral load test program. |
| Jerome SR 89 Emergency Slope Repair |
The area of Jerome, an old mining town on Highway 89A between Prescott and Flagstaff , was besieged by heavy rainfall in late December 2004. This led to the partial failure of the embankment and a dry-stacked rock wall, subsequently undercutting the northbound lane of Highway 89A. The Arizona Department of Transportation (ADOT) retained NCS to develop a plan for the emergency stabilization of the surficial slide failure and the permanent remediation of the undercut roadway. A soil nail retaining wall was used to remediate the failed portion of the wall. |
| SR 202L (Red Mountain Freeway): University to Southern |
This project involved the construction of 2 miles of depressed urban freeway including three new bridge structures, over 4,000 linear ft of retaining walls and other features. The project was also notable because its alignment crossed over a known earth fissure. |
| Veteran's Memorial Overpass |
Pima County Department of Transportation (PCDOT) has rebuilt the Veterans Memorial Overpass in Tucson , Arizona. The contracting company performing the construction submitted a value-engineering (VE) proposal to replace all Cast-in-Place (CIP) retaining walls on the Veterans Memorial Overpass (VMO) with Mechanically Stabilized Earth (MSE) walls. PCDOT retained NCS to assist with the evaluation of the VE proposal. |
| SR 80: Bisbee Sidewalk |
ADOT and the historic mining Town of Bisbee have requested EEC design a sidewalk that connects the Copper Queen Mine Tour with the scenic Lavender Pit Overlook. NCS provided a field and laboratory investigation, and recommendations for a "retaining wall" required on a portion of this project. As a result of extremely corrosive conditions, steep slope geometry in front of the wall and other factors, a concept was recommended involving supporting the sidewalk on columns socketed into rock as opposed to constructing a conventional retaining wall. |
| Miscellaneous |
A few award photos and some other things that don't really fit anywhere else. |
| Pusch View Bridge Defects |
NCS was asked by the Town of Oro Valley to help in setting up and interpreting drilled shaft integrity data for the Puch View Bridge over the Canada del Oro. Several shafts showed significant defects, and the contractor opted to expose some of them. The results were impressive. |
| Higgins Wall |
A distressed residential MSE retaining wall that NCS was asked to evaluate. |
| Ryan Dike |
The Ryan Dike was originally constructed in the 1970's to control the erosion of the banks of the San Simon River. 6 large breaches have developed in the dike, and NCS' client, Entranco (now DMJM), was tasked with surveying the dike and preparing a plan to repair it. NCS was tasked with performing test pits and evaluating the suitability of material sources along the dike for the reconstruction. |
| SR 264: Second Mesa Geofoam Wall |
The SR 264: Second Mesa project was a rockfall containment and safety project. Initial designs for this challenging project involved several side-hill MSE retaining walls. A value analysis was performed, and NCS was asked to help come up with alternative wall/fill schemes under our On-Call contract with ADOT. During the value analysis process, 2 walls were eliminated, and the other two were redesigned by the team to be an innovative hybrid of soil-nail wall and GeoFoam platform combined with pre-cast concrete facing. |
| US 60: Pinto Valley |
NCS Consultants, LLC (NCS) was retained by Kimley-Horn and Associates, Inc. (KHA) and the Arizona Department of Transportation (ADOT) to develop geotechnical recommendations for new side-hill fill slopes associated with the widening of the US 60 roadway between County Line and Pinto Valley Road in Gila County, Arizona. The existing side slopes are very steep and marginally stable. The challenge was to perform side-hill widening of these slopes while increasing the factor of safety versus global stability to levels acceptable to ADOT. |
| La Canada Dr. Soil Nail Wall |
NCS prepared performance specifications and reviewed third party soil nail wall designs on behalf of the Town of Oro Valley for a retaining wall along La Ca?ada drive. |
| I40: Coors |
NCS was a consultant to the PTG team on this project to advise them on issues related to MSE wall bridge abutments with drilled shafts behind them. |
| SR 170: Periot Lightweight Concrete Fill Retaining Wall |
Design of a light-weight concrete fill (LCF) retaining wall for a side hill roadway widening. Railroad tracks were within 20-ft of the toe of the existing slope, with a Southwest Gas Pipeline between the slope and the tracks. Additionally, the subsurface conditions consisted of soft, saturated, clayey soils. Settlements from surcharges needed to be minimized to avoid adversely affecting the pipeline or the railroad. Instead of ground improvement, a decision was made to use LCF with a unit weight of 30 pcf to mitigate adverse settlement. |
| I-10: Fort Grant TI Deep Soil Mixing |
NCS was subcontracted by Speedie and Associates, Inc. to provide recommendations for the design of ground improvement under the center piers of a new bridge at the Fort Grant Road Traffic Interchange (TI) in Wilcox, AZ. The Wilcox area has a complex geology, including Playa landforms with salt flats at the surface, and soft clay layers at depth. One or more of the clay layers appears to be underconsolidated. Drilled shaft and spread footings were found to have unacceptable settlements at the pier location of the new bridge, and NCS was tasked with providing ground improvement recommendations. Deep soil mixing (DSM) was selected as the method of ground improvement, with spread footings to be constructed over the improved subgrade. |
| First Ave. Bridge - Oro Valley, AZ |
This was the first avenue bridge project. |
| I-10: Miracle Mile TI Retaining Wall Distress |
Cracks had formed in the cast-in-place concrete facing of two MSE (mechanically stabilized earth) retaining walls along the WB lanes of I-10 at the Miracle Mile TI. NCS was tasked with determining the cause of the cracking, and providing recommendations for mitigation. Mitigation in this case consisted of installation of crack monitors and improvements to the clogged weep holes which had been allowing a build up of water pressure behind the walls. |
| UA CE Department Centennial Awards Gala |
In 2005 the U of A Civil Engineering Department held its Centennial Celebration and Awards Gala event. Ed Nowatzki of NCS was honored with the Centennial Professor award and Naresh Samtani was honored with the Centennial Distinguished Alumnus Award. |
| US 191: Coronado Trail Retaining Wall Inspection |
The Arizona Department of Transportation (ADOT) retained NCS as part of their on-call contract to prepare a condition assessment of 50 side-hill retaining walls along a 10 mile long stretch of US 191 (Coronado Trail) in Greenlee County north of Morenci. Most of the walls are dry stacked walls or rockery walls that were built in the early 19th century. |
| I-10: Cortaro Road TI Soil Nail Walls |
NCS performed design and post-design services for the widening of the Cortaro Rd. underneath I-10 by cutting into the embankment slope between the abutment and the pier and using soil nail retaining wall to stabilize the slopes. |
| I-17 MC Contract: Loop 101 to Carefree Highway |
The Arizona Department of Transportation (ADOT) is proposing to widen the existing Interstate 17 (I-17) as part of the Management Consultant Contract between Downtown Phoenix and Black Canyon City. The first phase of the project calls for widening of I-17 between SR 101L and Carefree Highway. ADOT retained Parsons Brinkerhoff (PB) to prepare the design for the 30% stage. NCS performed the geotechnical investigations under subcontract to PB. The reconstruction of mainline I-17 will include 13 bridge structures and pavement design. Some existing bridges are being widened on the inside, others are being replaced completely. Additionally, several new traffic interchanges (TI) are proposed for construction including bridge structures and possibly retaining walls. The field investigation program conducted by NCS included 50 borings for the various bridge structures and the pavement analysis. Due to the hard soils at the site, the tubex system (air rotary) was used for drilling the deep structural borings while conventional hollow stem augers were used for the pavement borings. |
| SR 90 Lightweight Concrete Fill |
The purpose of this project is to construct a Multi Use Pathway (MUP) along SR 90 between Fort Huachuca East Gate and North 7th Street in Sierra Vista. NCS performed field and laboratory investigations, provided earthwork factors, compaction factors, evaluated collapse potential, and provided recommendations for two retaining walls. One of the walls designed involved using a lightweight concrete fill to mitigate global stability. |
| U of A Science Center |
The U of A's Science Center project was originally envisioned to include a landmark pedestrian bridge structure spanning I-10 and the Santa Cruz River in Downtown Tucson. NCS performed the geotechnical investigation and design for this impressive structure before it was eliminated from consideration by the new U of A President. A new Science Center will still be built, and NCS will still be the geotechnical designer, so check back in the future! |
| Mt. Lemmon Catalina Highway Emergency Repairs |
At the end of July of 2006, a massive monsoon rain storm pounded the Santa Catalina Mountains northeast of Tucson. The USGS reported approximately 240 new slope failures occurred as a result of the storm. At least two notable failures occurred along the Catalina Highway that goes from Tucson to the town of Winterhaven and Ski Valley at the top of Mt. Lemmon. NCS was tasked by Pima County to design fixes for two of these sites. Both were fixed using soil nailing techniques. |
| Ed Nowatzki: 2007 Southern Arizona Engineer of the Year |
Ed Nowatzki was the recipient of the 2007 Southern Arizona Engineer of the Year award presented by the Southern Arizona Chapter of the Arizona Society of Professional Engineers. |
