Case Studies

Photo: Purchased image through photographer for GeoStructure rights

Other Categories
Brownfields
+
Commercial
+
Education
+
Government
+
Healthcare
+
Industrial
+
Residential/Hospitality
+
Sports/Recreation
+
Transportation
+

Education

Towson University Liberal Arts Building – Phase II

Towson, MD

DESCRIPTION

153,000 sf Liberal Arts Complex which includes impressive galleries, a writing center, additional labs, student areas and lounges.

LEED Gold Certified

CHALLENGE

Building loads ranged from 100 to 840 kips. Phase I of the complex incorporated a drilled shaft foundation system; however, due to scheduling concerns, an alternative was needed for phase II.

The building was sited such that footings for the western section of the building could bear on decomposed rock with an allowable bearing pressure of 7.5 ksf, but fill soils and loose residual silty sands required a deep foundation system in the eastern section. The soil conditions for the eastern section consisted of approximately 10 feet of loose silty sand fill, overlying 25 feet of natural, loose to dense residual silty sands, which were underlain by decomposed rock and highly weathered to weathered gneiss bedrock.

SOLUTION

Geopier elements were used to replace a drilled shaft foundation system. The original geotechnical report recommended that all shafts be a minimum of 36 inches in diameter so that the bottom could be inspected to verify shafts were bearing on suitable material.  Due to the variability of the weathering in the bedrock profile, drilled shafts needed to be socketed into rock with an RQD (Rock Quality Designation) of at least 50%.  The shafts were designed for an allowable bearing pressure of 40 ksf.

The general contractor, who was familiar with Geopier RAP elements, proposed an alternate of 30-inch diameter RAP elements.  The RAP elements supported spread footings designed for 6 ksf bearing and controlled settlement to less than 1 inch.  Having a designed system that was consistent with the spread footings used on the western section of the building simplified the design and construction sequencing for the GC and the owner.

The Geopier alternative proved to be faster and eliminated the risk of potential overruns associated with variable drilled shaft lengths, rock socket depths, and rock testing to find rock with an RQD > 50%.

Towson Sketch

Using ground improvement versus drilled shafts provided the owner the assurance that the foundation would be completed on schedule with no cost overruns and also contributed to the LEED goals for this project by using recycled concrete for pier installation.  Specific benefits included:

  • Ability to use spread footings for all the foundations
  • Eliminating the requirement to socket piers into rock or case holes for inspection and testing
  • Eliminating the risk of overruns due to encountering poor quality rock
  • Generating fewer spoils saving time and haul-off costs

Owner

Towson University - Towson, MD

General Contractor

The Whiting-Turner Contracting Company - Baltimore, MD

Architect

Burt Hill Architects - Washington, DC

Structural Engineer

ReStl Designers, Inc - Washington, DC

Geotechnical Engineer

EBA Engineering, Inc - Baltimore, MD

Product

Geopier GP3® System

Additional Education Projects

North Carolina State University – Center for Technology & Innovation Parking Deck

Raleigh, NC

Virginia Tech – Brodie Hall

Blacksburg, VA

Rowan University Rohrer College of Business

Glassboro, NJ

Walker Jones School

Washington, DC

Virginia Tech Rasche Hall

Blacksburg, VA

Howard University Residence Halls

Washington, DC

University of Mary Washington Dormitory (Eagle Village)

Fredericksburg, VA

Virginia Commonwealth University – Monroe Park Campus Dormitory and Parking Garage

Richmond, VA

Western PA School for the Deaf New Dormitory

Pittsburgh, PA

Boyce Middle School

Pittsburgh, PA

Virginia Tech Basketball Practice Facility

Blacksburg, VA

KIPP DC: LEAP Academy

Washington D.C.

Additional Education Projects

North Carolina State University – Center for Technology & Innovation Parking Deck

Raleigh, NC

Virginia Tech – Brodie Hall

Blacksburg, VA

Rowan University Rohrer College of Business

Glassboro, NJ

Walker Jones School

Washington, DC

Virginia Tech Rasche Hall

Blacksburg, VA

Howard University Residence Halls

Washington, DC

University of Mary Washington Dormitory (Eagle Village)

Fredericksburg, VA

Virginia Commonwealth University – Monroe Park Campus Dormitory and Parking Garage

Richmond, VA

Western PA School for the Deaf New Dormitory

Pittsburgh, PA

Boyce Middle School

Pittsburgh, PA

Virginia Tech Basketball Practice Facility

Blacksburg, VA

KIPP DC: LEAP Academy

Washington D.C.