Underpinning Contractor Case Studies Phoenix AZ

 
 

 

 
 
 
Underpinning Contractor Case Studies Phoenix by Arizona Helical Piers, LLC 480-854-7661
 
Stadium - helical pier case studies phoenix in Phoenix, AZ
Project:
AZ Cardinal's Stadium
Hunt Construction Group
Engineer:
Schuff Steel Co.
Ed Carroll/Ron Offenburger
Underpinning Contractor:
Arizona Helical-Piers Co.
Phoenix, AZ
 
Job Description:
Anchor cables in retention: Installation of 132 Chance SS-175, with double heliced leads to be used as roof support guy-wire tension anchors. This was to be done in two phases. The first phase was installation and the second phase was to uninstall the anchors.
In Tension:
All piers had to be pull tested at a 38 to 45-degree angle, to a minimum of 50-kips and to be held there for one minute with no shaft movement. This using two 3-ft. high I-beams, 40-ft. long and sitting on cribs.
Pier depths:
The minimum installed depth from the upper helix was 42-inches with a maximum of 77-inches. The area at one time was an ancient river bed. The soils were so bad that AHPC had to rock cut the leads to even get these depths. Even at these shallow depths all the piers held well.
 
Student Housing – The Suites Flagstaff, AZ
 
Project:
NAU Student Housing – The Suites
Flagstaff, AZ
Engineer:
Jeff Martin P.E.,M.S.C.E
Steelhead Engineering
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
Construction of Piers - helical pier case studies phoenix in Phoenix, AZ
 
 
Job Description:
New deep foundations for a pair of four story student dormitories on the campus of Arizona Northern Arizona University in Flagstaff, Arizona. General contractor hardison/downey construction, inc. was advised that the large settlement concerns indicated a deep foundation system. Highly variable site conditions would make foundation construction unpredictable and time consuming. hardison/downey construction, inc. approached AHPC to value engineer the pile construction prioritizing construction duration.
The Challenge & Solution:
The site is an old drainage course with weathered rock bearing strata overlain by an undocumented fill of sands and boulders varying in thickness from 0 to 40 feet. Excavation and re-compaction, drilled cast in place piers, driven piles and floating mat foundations were all rejected for performance, price or constructability reasons. Time being critical, the helical pier solution minimized required pier by pier design revisions that had to be approved by the engineering, contracting and regulatory stakeholders. Representative full-scale compression testing verified the capacity and stiffness of per plan installations and up to 70 piers requiring shallow pre-drilling and post grouting.
nstall:
Material distribution of 500 Chance SS175 Helical Piers. Pile engineering was completed by SteelHead Engineering of Freedom, California. Geotechnical engineering was by Speedie & Associates, Inc. of Phoenix, Arizona. Special inspection services were provided by Bingham Engineering Consultants, LLC.
Highway construction - helical pier case studies phoenix in Phoenix, AZ
 
Riparian Preserve City of Gilbert, AZ
 
Project:
Riparian Preserve
City of Gilbert, AZ (Library)
Engineer:
Ed Glenn Glendale, AZ
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
Pier installation - helical pier case studies phoenix in Phoenix, AZ
 
Job Description:
AHPC installed 26 Chance Helical-Piers to anchor and connect 254 ft. of floating boardwalk.
4in. T-40 galvanized pipe was used to slip over the piers and 17/8 pipe for cross member supports. Piers were installed to depths up to 24ft.
 
 
Floating boardwalk - helical pier case studies phoenix in Phoenix, AZ
 
Underwater connecting work - helical pier case studies phoenix in Phoenix, AZ
 
 
Tieback Application Prescott, AZ
 
Tieback - helical pier case studies phoenix in Phoenix, AZ
 
Project:
Tieback Application
Prescott, AZ
Engineer:
Glen Copeland, Geotech.
Prescott, AZ
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
 
Job Description:
This two year old custom home was built 1/3rd on a fill wedge using a solid grouted concrete wall as a retention structure. 2/3rds of the home cantilevered out over a canyon supported by beams and posts. With the introduction of water, the retaining wall began to bulge and crack.
Repair:
11 Chance Helical-Piers with 8" helices were installed by AHPC in tension to act as a tieback. Piers were installed to an average depth of 29ft. The piers were tied together with a whaler made up of two continuous 6in. steel channels. Each pier was set in tension and tested with cracks grouted. The retaining wall was secured and no further movement will occur.
 
Del Webb's Sun City Sun City West, AZ
 
 
Wall - helical pier case studies phoenix in Phoenix, AZ
 
Project:
Del Webb's Sun City
Sun City West, AZ
Engineer:
Bingham Engineering, Inc.
Daniel Bingham
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
 
 
Job Description:
The Del Webb Corporation called on AHPC to tieback (using the Chance Helical-Pier) 333ft of reinforced block retaining wall.
Repair:
A total of 36 Helical-Piers were installed to stabilize and stop further movement. The heel side of the wall had to be hand dug, drain holes drilled and tehn backfilled with gravel for drainage.
AHPC received a letter of recommendation from the Del Webb Corp. for its courteous attention and respect shown towards the many folks whose yards we were working in.
 
Commercial Underpin Bank Building Flagstaff, AZ
 
Office entry - helical pier case studies phoenix in Phoenix, AZ
 
Project:
Commercial Underpin Bank Building
Flagstaff, AZ
Engineer:
Sheppard/Wesnitzer, Inc.
Rodger Hocking
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
 
Job Description:
This 3-story building owned by Dr. Anthony Choi of Flagstaff exhibited signs of distress and settlement.This 3-story building owned by Dr. Anthony Choi of Flagstaff exhibited signs of distress and settlement.
Repair:
A total of 6 Helical-Piers were installed to stabilize and lift the side of the structure back to level. Depths reached by the piers ranged from 39ft. to 68ft. before a proper torque was reached.
Note: AHPC reached depths of over 60ft. at the first two pier sites. A switch to multiple helix leadswas done for the purpose of reaching torque faster at shallower pier depths and to save steel cost. This reduced the depths needed to reach the proper torque to 40ft.
 
Residential Underpin Gilbert, AZ
 
Front entry of residences - helical pier case studies phoenix in Phoenix, AZ
 
Project:
Residential Underpin
Gilbert, AZ
Engineer:
Declined
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
 
Job Description:
This single story home located in Gilbert, Arizona experienced front and side settlement due to the area's expansive soils. The property owners were concerned with what they believed to be the inevitable destruction of many landscaping plants. We were able to save most of them.
Repair:
AHPC used 8 Helical-Piers to stabilize outside load bearing walls. Because of front decorative retaining walls and foliage, all access holes to reach footing had to be hand dug and our remote hydraulic powered Guided Mast System (GMS) was employed to do the actual pier installations.
 
SSA/Registrar of Contr. Office City of Show Low, AZ
 
Tightening torque bar - helical pier case studies phoenix in Phoenix, AZ
 
Project:
SSA/Registrar of Contr. Office
City of Show Low, AZ
Engineer:
Speedy & Assoc.
Phoenix, AZ
Underpinning Contractor:
Arizona Helical-Piers, L.L.C.;
Gilbert, AZ
 
Job Description:
This building is home to the Social Security Administration and the Registrar of Contractors offices in Show Low, AZ. Four of the support columns were sinking.
Repair:
Four Chance Helical-Piers with 8 inch helices were used placing one at each column site and installed with a hand operated, 2,500ft. lbs. powerhead. The pier depths were approximately 8 to 10ft. at 25 kips.