George Nathanailidis and his TENA SA crew faced an enormous soil compaction challenge on a dam jobsite near Triantafullia, northern Greece.
TENA was responsible for placing 42 m (138 ft) of compacted materials on an existing embankment of 33 m (108 ft). The earthmoving volume for the massive earthen dam exceeded 350,000 m3 (457,765 yd3). The material had to be applied in 20 cm (7.8 in) layers, and compacted to 15 cm (5.9 in)—at a length of 364 m (1,194 ft) and at a width of 18 m (59 ft).
Volume was only part of the challenge. “We worked in sandy clay,” Nathanailidis says. Achieving uniform compaction would prove difficult, while monitoring densities would be challenging and less than comprehensive.
TENA SA turned the nightmare job into a dream with the help of a new machine-integrated soil compaction measurement technology called Machine Drive Power, or MDP.
“MDP saved us considerable time and certainly money,” says Nathanailidis, president and chief executive officer of TENA SA, one of the largest construction companies in northern Greece.
Nathanailidis has numbers that support the statement:
MDP is a significant change in compaction measurement technology. It is a not a breakthrough in how machines compact. Instead, it evaluates the rolling resistance.
That resistance provides an indication of soil stiffness and load-bearing strength, and whether compaction is adequate to structurally support the road, parking lot, building—or whatever is planned for the site.
The ultimate benefit of MDP, a proprietary technology developed by Caterpillar, might be summed up in one word: uniformity. Is the entire site compacted the same way, or are there areas where structural integrity is compromised?
Historic methods of testing can only provide a snapshot, and are no guarantee of uniformity. Typically only 1 percent of the jobsite is tested. MDP acts as a proof roller while it works, enabling much faster discovery of inconsistencies across the entire jobsite. It works in any type of soil, and performs whether the compactor is smooth or padfoot, vibrating or static.
The Dam Jobsite
Before the Triantafullia dam project began, authorities set the following requirements to ensure proper compaction:
“I would recommend others use it because of fast measurement compaction, accuracy, reliability and increased productivity,” Nathanailidis says.