While Conco is justifiably proud of breaking the World record for the largest continuous mat pour, we are even more proud of doing it safely.  Our commitment to safety began with the vision from Conco’s Southern California General Manager, Rick Parker.  Five months prior to the pour, he invited John Messing, Conco’s Safety Director, to participate in the planning meetings for the Grand Pour.  Rick has learned from his years of experience that projects go more smoothly when the safety department is involved early-on to ensure that safety is built into the overall work plan.

*Photos provided by Gary Leonard

Rick also made the prudent decision to devote the first-quarterly company safety meeting in January entirely to the safety of the pour.  During the meeting, Rick Parker and Pumping Manager, Doug Marquis, provided an overview of the Wilshire Grand jobsite along with the challenges, unique project features, and logistical considerations of the job.  John Messing spent the balance of the time devoted to discussing the importance of pre-task plans.  He assigned three sub-groups to develop such plans regarding the work that they would perform.  At the conclusion of the safety meeting, the pumping crew, place and finish crew, and street-level supervisors all had a unique, customized pre-task plan that was used as the basis to ensure their workers understood the hazards of the work and how to mitigate them.

The end result of the successful well-thought out plan was a highly professional team effort from all Conco employees.  The entire team—at all levels—executed the plan to perfection, which resulted in zero injuries for this world record continuous concrete pour.

To successfully complete the world’s largest continuous mat pour, one of the biggest challenges Conco faced was to find ways to unload 120 – 150 truckloads of concrete per hour. With the need to unload so many trucks in such a short period of time, Conco’s plan called for thirteen points of placement in the mat foundation.  However, only two sides of the project were accessible from the street.

Since the site only provided access for seven pumps to be positioned to pump directly into the building foundation, Conco’s plan needed to have pumps that were pumping into pumps.  Pumps were dropped by crane into the excavation site and two placing booms were fed from pumps nearly 400 feet away.  In all, fifteen boom pumps, two high-pressure stationary pumps, two placing booms, and more than 2,500 feet of pipe operated throughout the pour to get the concrete to the foundation.  Four of the pumps on this project were new along with a brand-new placing boom.  In addition to this equipment, three boom pumps were parked in close proximity to the project in case of a breakdown.  None of the backup pumps were put into service as the pumps on the job performed near flawlessly.

To complete the rest of this signature project, the two high-pressure stationary pumps will remain on-site for the project’s duration.  One of the pumps is a recently purchased electric pump.  This pump is the most powerful electric pump operating west of the Mississippi and is capable of pushing concrete to the top of the structure.  It provides our client, the Turner Construction Company, with a zero-emission pump that operates with less noise than a typical diesel pump.

By the end of Conco’s record breaking mat pour, the pumping work all went successfully according to plan.  Special recognition goes to our ACPA trained pump operators, and our mechanics that spent countless hours preparing the equipment for the pour.

*Photos provided by Gary Leonard

Starting at 4:47 p.m. on Saturday, February 15, 2014, Conco broke the Guinness World Record for the largest continuous mat pour in 18 ½ hours (1 ½ hours under the projected time).  To verify the event, there was an official Guinness World Records adjudicator on-site.  The mat pour was for the new Wilshire Grand Center that is being constructed in downtown Los Angeles, and is slated to become the tallest building in the U.S. west of the Mississippi.

*Photos by Gary Leonard

After some 5 months of excavation and shoring, Conco was finally ready to begin the preliminary mat foundation work.  Starter footings and elevator pits had to be constructed before the nearly 7 million pounds of mat reinforcement was installed.  Then came 18 miles of cooling pipes for thermal control.  We were ready to go with a couple of days to dot the i’s and cross the t’s.  We began the set ups for pumping which involved strategically placing 19 pieces of concrete placing equipment in and around the construction site.  It was now time to place this nearly 20 foot thick mat foundation.

The massive mat pour required a fleet of 208 trucks that each made 10 to 14 concrete drops for a total of 2,100 trips over the 18 ½ hour period.  All of the concrete was provided by eight concrete batch plants operating at full capacity and located within a 20-mile radius of the job site.  The success of the pour depended upon everything going exactly as planned and with contingencies in place to reroute trucks around any traffic jams.  Trucks had to arrive on time since concrete needs to be poured 90 minutes after it is mixed. Several streets in the area were closed off to traffic.

Prior to this record breaking event, the largest continuous mat pour had been for the Venetian Hotel in Las Vegas in 1999.  During that event, 21,000 cubic yards of concrete were poured.  For the Wilshire Grand, 21,200 cubic yards of concrete were poured with an official finish time of 11:30 a.m. Sunday morning.  The skyscraper is expected to be completed in 2016 and opened to the public in 2017.  The Wilshire Grand will be 1,100 ft. tall, to include a 900-room hotel, office and convention space as well as five levels of subterranean parking.