Mud.
Lots of it.
The exposed dirt at the Nissan Manufacturing Plant in Canton, MS, was thoroughly soaked by intense rainfalls in May and June 2003.
Tom Elmore, president of Eutaw Construction, looked out at the site before him and saw machines sitting idle. The site was completely underwater.
Articulated trucks trudging through deep mud is one thing but through a lake is another. Only one of Elmore’s five 35-ton (31.8 t) articulated trucks was working. The other four sat in a row just off the excavation site.
Yet, the appearance of this lake meant that the engineered profile of this site was working perfectly.
“It’s a retention pond,” said Elmore. “We have to excavate about another 160,000 yards out of it to get to the point where it will hold enough water. But we can’t work in this.”
Finding a Solution
In 1980, Elmore founded Eutaw Construction, based in Aberdeen, MS. Having previously held numerous engineering and management positions with Granite Construction Company of Washingtonville, CA, Elmore spent time in Mississippi on a lock and dam project being constructed by Granite on the Eutaw formation. Over time, he decided to start his own company. Eutaw Construction now performs a variety of highway and heavy site work as well as water, sewer and storm drainage work in Mississippi. The company is licensed in six states.
In December 2000, Nissan Motor Company announced it would build a new manufacturing plant in Canton, helping to improve the region’s struggling economy by turning it into a hotbed for construction.
In addition to the new construction work, it will bring approximately 18,000 to 26,000 jobs to the region, spread across the manufacturing plant, commercial properties and support industries. Eutaw Construction has been part of the process from the beginning.
“We originally did the clearing and drainage work on this project,” said Elmore. “Then, we did Phase B, which included a third of the pad for the building. We also did the grading and drainage work for the parking lot and a relocation of the railroad and a staging area for the rail cars.”
Part of the original site work included the excavation of 1.4 million yds. (1.3 million m) of dirt in 50 days. With the site extremely wet, Eutaw trucked in lime to help solidify the ground and enable Eutaw’s fleet of scrapers to work and remove the required amount of dirt.
Despite the lime, the moist earth remained a problem. A 405 hp (302 kW) Komatsu D275A-2 dozer was called in to push the scrapers through.
With the excavation of 160,000 yds. (146,304 m) of dirt for the Nissan retention pond ahead, Elmore expanded his equipment fleet. He worked with John Lyle, president of Great Southern Tractor, on the purchase of five Komatsu HM350-1 articulated trucks.
When not completely underwater, Elmore decided to use Komatsu 35-ton (31.8 t) HM350-1 articulated trucks and a PC400LC-6 excavator to top load and remove the existing soil from the site. This combination beat the scrapers used by Eutaw on flat, dry sites.
Hauling material more quickly and effectively than a scraper in these conditions, the HM350s were loaded by PC400LC-6 excavators in five passes on their way to the dumpsite. An excavator/articulated truck combination often outperforms scrapers in a number of ways.
“The scrapers simply couldn’t stand up out here,” said Elmore. “You’d never get them out, and you’d have to top load them light so they could get around the site.”
“Where Eutaw excels is in its equipment diversity,” added Lyle. “There were no haul roads. Articulated trucks will work where scrapers won’t. That’s what led him to the purchase of these trucks. The way Komatsu made the commitment to build this truck from the ground up, to give it an extremely long life expectancy, I felt confident in offering it to Eutaw, and it proved a good truck.”
Articulated trucks are efficient hauling over long distances with a lower weight per rated load ratio, a major factor for Eutaw as the excavated material was hauled to the other end of the Nissan site. Scrapers require dozers to push them in difficult conditions, if able to operate at all, as rough terrain and the presence of large rocks can make a scraper obsolete. In this extremely Mississippi wet season, a scraper would have sat idle while waiting for the site to dry.
The Equipment
Outfitted with a 389 hp (290 kW) Komatsu SAA6D140E-3 engine, the HM350-1 articulated truck can haul a 35-ton payload at 34 mph (54.7 kmh).
A continuously oil-cooled multiple disc retarder allows for deceleration without frequent use of the brakes, permitting safe travel at higher speeds, even when traveling down long, steep slopes. The braking system is fully sealed for protection against contaminants, making it more reliable, responsive and giving it a long service life.
The front and rear hydro-pneumatic suspension system ensures a smooth ride even in rough conditions, critical for most articulated truck applications.
“We had some other trucks out here that were slightly bigger than [the HM350],” said Barry Jenkins, job superintendent. “That was the only difference. [The HM350s] seemed to go places where the others didn’t, and we had an uphill pull all the way. These trucks just came and went like it was nothing.”
The ability to wall through even the wettest, toughest conditions can be attributed largely to the design of the Komatsu Advanced Transmission with Optimum Modulation Control System (K-ATOMiCS). The HM350-1s six-speed, fully automatic transmission automatically selects the appropriate gear based on vehicle speed, engine rpm and chosen shift position. This allows for smooth and powerful acceleration and smooth downshifting, sensing whether the body is full or not.
“These trucks can bust through [tough conditions] every bit as good as the others we tested, if not better,” said Elmore. “They seemed to be quicker too –– we’ve been satisfied with them.”
Not so new to the Eutaw fleet are the PC400-6s being used on this and many other of its sites throughout Mississippi and Alabama. Used at the Nissan plant to top load the articulated trucks, Eutaw put nearly 4,800 hours on the PC400-6 at the Nissan site in just two years.
The PC400LC-6 excavator features the HydrauMind hydraulic control system, offering load sensing and pressure compensated valves that automatically adjust to each working application. Made up of closed-center, load-sensing valves, the system reacts in direct proportion to pressure applied by the operator to the controls, improving responsiveness for easier fine-control and lifting operations.
The PC400LC-6 also uses the 306 hp (228 kW) Komatsu SA6D125E-2 engine.
For more information, call 662/369.8868 or visit eutawconstruction.com.
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