Photo provided by Conco
Photographer: David Sievert,

One South Market

Location: San Jose, CA
General Contractor: Balfour Beatty Construction
Concrete Contractor: Conco Cement Company
Concrete Supplier: Central Concrete Supply Co., Inc,

Project Overview

23-story tower, 312-unit apartment project
6,000 sq. feet of ground floor retail
395-stall parking structure
Cubic yards of concrete: 25,000

A Closer Look

Conco and Central Concrete collaborated on critical path scheduling to ensure the successful completion of a 6-day cycle for each of the 23 floors.

6-day Cycle

Day 1: Conco pours the deck
Day 2: Conco pours the columns and walls
Day 3: Conco flies the forms to set the stage for the MEP and rebar
Days 4-6: MEP & Rebar contractors execute their scope of work for the floor

Concrete Mix Requirements

To successfully execute the aggressive construction schedule, Central Concrete designed, tested and
implemented several new mixes, including a:

  • 3000 psi at 2-days — .025% shrinkage mix for the post-tensioned decks
  • 7000 psi shotcrete
  • Proprietary high early (5000 psi at 5-days) -low heat of hydration mix for mass concrete. This mix utilized slag and fly ash to replace 50% of the cement, as well as proprietary technologies and materials to activate the SCMs and provide the high early strength.

Return to Project Listing »


Bookmark and Share


Facebook LinkLinkedIn LinkYoutube Link