1. International Workshop on Micropiles May , 2002 Venice, Italy Full Scale Field Tests on Single Micropiles and Groups/Networks of Titan Micropiles and Future Initiatives
Dr. Donald A. Bruce – Geosystems, L.P.
Gary M. Weinstein – Polytechnic University

2. SUMMARY
- Full scale field tests funded by U.S. Military, installed and tested by Structural Preservation Systems (SPS) in Baltimore, MD, and designed and analyzed by Geosystems, L.P. - Bulk of tests used a total of “self-drilling” Titan Ischebeck micropiles, installed and tested in three discrete phases: > Phase I: Sept Feb > Phase II: August > Phase III: September 2001
Phase I : 28 grouped/networked, 6 singles (9’)
Phase II: 32 grouped/networked, 33 singles (4’/9’)
Phase III: 8 grouped/networked

3. Solution: TITAN Injection Anchor
Overall Program Goals
UNIQUE
Environment
- Rock
- Soil (Gravel, Sand, Silt, Clay)
- Frozen Ground Loads
- Concrete and Asphalt - Axial, Shear, Torsion (Static/Dynamic)
Materials Equipment
- One “Anchor” - One “Tool”
- Grout - Self Contained Power
Installation Logistics
- One “Process” - Lightweight (threshold)
- Clean - Packaging (threshold)
- User Friendly - Economically Feasible
- Time - Inventory/Field Reduction
Solution: TITAN Injection Anchor
Self-Drilling, Grouted, Continuously Threaded Tubular Anchor
Superior Shear, Bending & Structural Characteristics
Ultimate bond values for individual vertical Titans in sand ranged from 1.72 to 2.63 kips/ft (avg. 2.2 kips/ft). (21 to 27 psi: avg. 24 psi). For the two shortest piles in clayey fill with no other overburden cover, the values were several times lower.

4. Program Test Objectives
Phase I: - Lateral and tensile testing of groups/networks. Tensile testing only of vertical elements. Phase II: - “Specialized” testing of groups/networks. Tensile testing only of vertical elements utilizing both cement and solution grouts. Phase III: - “Specialized” and Lateral testing of groups/networks utilizing both cement and solution grouts.

5. As-built pile group layout.

6. Plan view of various test elements (Phase I).

10. Cyclic Lateral Loading of Micropile
Future Work
Cyclic Lateral Loading of Micropile
Groups/Networks (Theory & Field)
Purpose? Design Standards and Specifications
Who Benefits?
Private Industry (Contractors, Engineers, Consultants)
Federal/State Gov’t (FHWA, State DOTs, etc.)
Academia (the cycle continues . . .)
What Benefits?
Transportation Projects (Highways, Bridges . . )
All Deep Foundation projects (new/retrofit/etc.)
Industry in General
> Future Work – based on lessons learned from Baltimore/FOREVER/Lizzi/Japanese, et. al. >>>> see
> The cycle continues: Applied Research => Analysis => Understanding + Lessons Learned = More Applied Research and Theory
1. FHWA
State-of-Practice Review
Including Research Needs Assessment on Drilled and Grouted Micropiles (Contract No. FHWA-DTFH61-93-C-00128) - July 1995
Other undertakings, studies
2. FOREVER ( ): French National Research Project
$7,000,000 between French Gov’t, Partner, and FHWA
Isolated, Groups & Networks (static and Seismic)
Full-scale tests, Shaking table, Centrifuge, FEM, numerical studies
3. ADSC Involvement
4. TWG
5. National Geotechnical Experimentation Sites (NGES)
6. Private Industry (% of construction costs towards full-scale instrumentation and testing/research on site)

11. Future Work (cont..) How Do We Get There?
Practical and Applied Research that . . .
is Conducted in an Environment of Sharing & Cooperation
incorporates Lessons Previously Learned
is of Benefit to All
Cooperative Environment =>> see IWM Vision Statement >> Philosophy of Information Sharing for Benefit of Community 1.

12. Future Work (cont..)
With this Synthesis of Applied & Theoretical Research
FHWA: Further Study of Micropile Network Experiments
Review recently conducted full-scale experiments
Interpret . . .
Summarize similar experiments  Future Research Needs
Academic Research: Lateral Loading of Micropile Networks
Rigorous Cycled Tests
Instrumentation & Monitoring
Lab & Field Testing of Soils, FEA?
Analyze, Predict, and Conclude 1.
FULL
CIRCLE