Central Park Tower

New York, NY

Award: Innovative Applications

Project Team

Owner: Extrell Development Company

Contractor: GC-Lendlease/ Concrete - Pinnacle Industries

Architect: Adrian Smith + Gordon Gill Architecture

Engineer: WSP Global

Concrete: Empire Transit Mix

Slag Cement: Lehigh Hanson

Case Study

In this project a total of 100,000 cubic yards of concrete was used. Slag cement enhanced the project by:

• High PSI (16k psi)

• Sustainability (40% slag cement mix offered a significant co2 reduction)

• Pumpability

• Low heat of hydration for mass pours (70% slag) which were 12 feet thick.

The use of slag cement resulted in structural, sustainable and mass concrete attributes.

This tower is a super- tall skyscraper known as one of a handful of “Pencil-Towers” in the world. It is the tallest primarily residential building in the world, tallest building in the western hemisphere, and the tallest roof in the western hemisphere. This project has a 28 foot cantilevered section that starts at 300 feet above ground, over an adjacent building, and reaches up 1,200 feet above.

Application Type

% Slag Cement Replacement	30 to 70% depending on application
% Portland Cement	70 to 30% depending on application
% Portland Limestone Cement	None
% Other SCM (if applicable)	2 to 4% silica fume depending on application
Aggregate	#67 and fine agg
Water/cement ratio	.28 to .38
28-day Strengths	9,000 to 14,000 psi depending on mix
56-day Strengths	12,000 to 18,000 psi depending on mix