Design-Construction of the Paramount – A 39-Story Precast Prestressed Concrete Apartment Building

Robert E. Englekirk, Ph.D., P.E., S.E.

Consulting Structural Engineer, Englekirk Systems Development, Inc., Los Angeles, California

Also, Adjunct Professor, University of California at San Diego

What distinguishes this building from the other highrises surrounding it is that the structure incorporates a novel precast hybrid moment resisting frame that is particularly effective in the severest seismic regions of the United States and indeed the world.

As such, The Paramount is not only the tallest concrete structure built in Seismic Zone 4, but it is also by far the tallest precast, prestressed concrete framed structure built in a region of high seismicity.

From a precast concrete perspective, it is the first major high rise building to be braced by an architecturally finished exposed concrete ductile frame. The reinforcement used to create this ductile frame includes both post-tensioning strand and high strength mild steel reinforcing with a yield strength of 120 ksi (8280 MPa). This combination of materials also represents a significant technological breakthrough.

The accomplishment of these milestones is a credit to the courage and perserverance of the design-construction team:

• Owner: Third and Mission Associates, Inc. – For courageously accepting a concrete 

   high rise building with a brand new structural bracing system in a very severe seismic

   area.

• Architects: Kwan Henmi, Architecture and Planning, and Elkus/Manfredi Architects,

   Ltd. – For very imaginatively integrating the structural framing system into the

   architectural design, and thereby creating a very functional and beautiful building.

• Structural Engineers: Robert Englekirk Consulting Structural Engineers, Inc. – For

   pioneering the structural engineering concept and developing the details of the bracing

   system for this building.

• Contractor: Pankow Residential Builders II, Ltd. – For enthusiastically embracing the   

   seismic bracing system and sponsoring the necessary research to test the system at the  

   University of Washington.

How the design-construction team realized their dream is the subject of his paper.

References

Warcholik, G., and Priestley, M. J. N., “Structural Systems Research Project: High Strength Concrete Joints Tests – Series 3, Report No. TR-98/12,” University of California, San Diego, July 1998.

Nawy, E. G., Prestressed Concrete: A Fundamental Approach, Third Edition, Prentice Hall, Upper Saddle River, NJ, 2000.

Englekirk, R. E., Seismic Design of Concrete and Precast Concrete Structures to a Performance Criterion, John Wiley & Sons, Inc., New York, NY, 2003.

Rahman, A. M., and Restrepo, J. I., “Earthquake Resistant Precast Concrete Buildings: Seismic Performance of Cantilever Walls Prestressed Using Unbonded Tendons,” Civil Engineering Research Report No. 2000-5, University of Canterbury, Christchurch, New Zealand, August 2000.

ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-99),” American Concrete Institute, Farmington Hills, MI, 1999.

Holden, T. J., “A Comparison of the Seismic Performance of Precast Wall Construction: Emulation and Hybrid Approaches,” Civil Engineering Research Report No. 2001-4, University of Canterbury, Christchurch, New Zealand, April 2001.

Englekirk, R. E., “An Innovative Design Solution for Precast Prestressed Concrete Buildings in High Seismic Zones,” PCI JOURNAL, V. 41, No. 4, July-August 1996, pp. 44-53.

Englekirk, R. E., and Selna, L.G., “Criteria for the Design of Prefabricated Concrete Systems,” ATC Proceedings of a Workshop on Design of Prefabricated Concrete Buildings for Earthquake Loads, April 27-29, 1981, pp. 639-656.

Englekirk, R. E., “Overview of the ATC Seminar on Design of Prefabricated Concrete Buildings for Earthquake Loads,” PCI JOURNAL, V. 27, No. 1, January-February 1982, pp. 80-96.

Englekirk, R. E., “An Evaluation of the State of the Art in the Design and Construction of Prefabricated Buildings in Seismically Active Areas of the United States,” Earthquake Resistant Reinforced Building Construction, June 1978.

ACI Innovative Task Group 1 and Collaborators, “Acceptance Criteria for Moment Frames Based on Structural Testing and Commentary,” ACI Proposed Provisional Standard (ACI T1.1-XX), American Concrete Institute, Farmington Hills, MI, undated.

Cheok, G. S., and Lew, H. S., “Model Precast Concrete Beam-to-Column Connections Subject to Cyclic Loading,” PCI JOURNAL, V. 38, No. 4, July-August 1993, pp. 80-92.