College of Engineering News • Iowa State University

CoE alumni help develop equipment to bring trees to 9/11 memorial site

Living in small-town Iowa doesn’t keep someone from impacting the world. Chris Holland (BSEE ’99), president of Holland Moving & Rigging (HMR) Supplies in Forest City, Iowa, helped bring a symbol of hope, renewal, and rebirth to the families of 9/11 victims. He designed equipment to plant trees in New York City’s 9/11 Memorial Plaza, which opens on September 11, 2011, the 10-year anniversary of the attacks on the World Trade Center.

Chris HollandHolland’s involvement with the 9/11 memorial began in 2009 when he was first approached about designing a custom piece of equipment to transport trees weighing up to 10 tons. In fall of 2010, Holland’s company was asked to create the equipment to plant approximately 85 of the over 400 swamp white oak trees on the elevated 9/11 Memorial Plaza that were not easily accessible via a crane—mainly the trees around the fountains and other difficult to reach areas. Holland’s company quickly began designing and fabricating the Straddle Mover and finished creating it within 12 weeks.

“It was a very tight deadline, but our company put forth the extra effort involved to help keep the 9/11 memorial on schedule,” Holland says. “It was important for the equipment to be able to carry the tree on the center of all the axles, capable of traversing sideways, and able to negotiate openings on the surface of the plaza for access, equipment, and a museum, requiring low ground pressure and a wider tire base.”

According to Holland, the knuckle suspension can lift and lower the frame and load up to 20 inches, while the standard dolly equipment has a lifting cylinder with only 16 inches of stroke. The block and cable system can lower the load below ground level, and 135 degrees of steering allows the Straddle Mover to negotiate the tight quarters on the plaza.

Although the Straddle Mover, which is controlled by a single operator and a remote control, was originally designed for moving trees, it also can be used for bridge deck replacement. Holland says upgrading bridges has been a high priority in the past couple years, and an easier method of upgrading the bridge decking will reduce the downtime for bridge repair.

HMR Supplies was founded as part of Ron Holland Housemoving in 1981. Ron Holland, Chris’ father, began designing and manufacturing Holland Dollies to provide a better and safer product for the structural moving industry. Chris went to work full-time in the family business in 2000 after graduating from Iowa State. In 2007, HMR Supplies was officially incorporated, and Chris became president.

“I have used my engineering education extensively throughout our business development. Iowa State provides a strong core engineering program that has enabled me to excel in the cross-disciplinary design required for this project,” Holland says. “Electrical engineering has played a role in many aspects of our business—from setting up our computer server to applying electrical engineering concepts to hydraulic control systems.”

In addition to Holland, two other Iowa State College of Engineering alumni played a part in the project. Senior design engineer Gus Marmaras (BSIE ’97) led the project and provided all on-site training in New Jersey at the tree farm, and Chris’ wife Natalie Hammer (BSAerE ’95) also works for the family business.

“Taking on the project, we knew it would be a lot of work,” Holland says. “But we were excited to be able to be a part of the 9/11 memorial. This was a way that Iowa could contribute to the memorial and honor all those who were affected by the tragedy on September 11, 2001. Everyone remembers what they were doing that day, but not everyone has the opportunity to contribute in such a significant way. Years from now, we will be able to go and see the trees and know that our company from the heartland of America was able to be a part of an amazing memorial.”