Trimble GCS900 3D Machine Control System Supports the Reinforcement a 1030 meter flood embankment wall in Wroclaw, Poland
The district of Kozanow in Wroclaw, Poland was ravaged by severe flooding in the mid-1990s and again, twice, in 2010. A reliable temporary flood solution was construed and in place for several years. When it was time for a replacement, the Ziajka Zbigniew Company won the call for tenders that was announced and supervised by Wrocławskie Inwestycje. It was determined that the temporary flood solution was to be replaced with a solid, 1030 meter long flood wall.
Construction of the shaft of the flood wall could only been started after resolving all of the ownership issues, and the settlement of disputes with landowners. On the north side of the wall, the area is surrounded by allotments, behind which flows the river Ślęża. Nearby is the Oder River mouth. In the case of a high level of the Oder River, Ślęza recedes and floods the allotments, which are located adjacent to a housing estate. The design determined the construction of shaft would be 1030 meters long, 3 meters high, 30 meters wide at the base, and 4 meters in the crown.
"Work started in March 2012 and is to be completed by May 2013," said Jacek Ziajka, a representative of the prime contractor. "Besides the construction of the shaft, the project also includes a construction of a service road, pedestrian and bicycle path on the top of the shaft and the correction of the EQ sewage of Oder."
Mounted on a the cab of the compactor, the GNSS receiver uses satellite signals and radio engineering system for communicating with its own reference station, receiving corrections from the GPS station network ASG-EUPOS.
The Kozanów Association, which represents the community of 30,000, was tasked with supervising the construction of the embankment. Representatives of the Association control the construction of shafts - both in terms of timing, as well as the works themselves.
"With this kind of critical investment, the priority for us is always the time and precision of the work," said Ziajka. "Currently we are working with heavy equipment. Our machinery is equipped with the Trimble 3D GCS900 Machine Control System, which works based on GNSS technology. We are well prepared - in a situation of increased rainfall and flooding danger, we are able to build a temporary, emergency shaft in one week - this is our agreement with the investor."
Excavators equipped with Trimble 3D GCS900 Control System, which work based on GNSS receivers (Global Navigation Satellite System) to ensure the accuracy within tight parameters. Tilt sensors mounted on the excavator bucket, arm and the boom of the machine and biaxial inclination sensor located on the machine frame provide guidance for the equipment. With this configuration and the graphical display in the cabin, the operator is continuously informed about the bucket position and can compare it to the design (including depth and slope) to perform precisely, timely and safely.
Trimble CCS900 3D measures in real-time density of the material during the passage of the vibrating cylinder.
The Trimble 3D GCS900 system was also used on dozers during the embankment project. The automatic hydraulic machine control solution allows the blade's height and tilt adjustments to mirror exactly to the project design specifications. GNSS receivers use satellite signals and improvements from the reference station located near the construction site to guide the blade. In real-time the machine uses horizontal planes as well as the corresponding declines - and in a single pass the bucket scoops the right amount of material. This eliminates the need for staking and constant grade checking. This reduces strongly (up to 80%) the amount of time required to complete the work. It also saves fuel and makes it easier for a less experienced operator (display in the cab + running "along the project") to reach the accuracy required on the project, which is up to 2 to 3 centimeters.
"Our operators recognize the advantages of intuitive work with the system and do not want to go back to using the conventional methods," said Ziajka.
Systems operate based on the 3D terrain models prepared in the Trimble Business Center - Heavy Civil Edition, complex geodesic design software. After conversion to the correct format, the project is loaded on the machine.
"Additionally, we also equipped our compactor with the same high-precision 3D compaction control system," said Andrzej Rozmarynowski, a consultant to the main contractor. "This is the first application of the Trimble 3D CCS900 compaction control system in Poland."
The Trimble 3D CCS900 Compaction Control System measures, in real-time, the density of the material during the passage of the vibrating cylinder. The system consists of mounted in the machine GNSS receiver, which uses satellite signals and precise CM310 density sensor, which bases on the resonance vibration indication of the machine.
"Working in the field with Trimble 3D CCS900 system we get the density values on an ongoing basis, together with their precise location on the project," said Rozmarynowski.
Mounted on a the cab of the compactor, the GNSS receiver uses satellite signals and radio engineering system for communicating with its own reference station, receiving corrections from the GPS station network ASG-EUPOS. Because of its own base station and radio communication, the system receives information about the location 20 times per second and is able to precisely determine the position, even at high speeds of the machine.
Intuitive cab screen Trimble CB450 provides the operator with the necessary information to control machinery.
The system calculates the exact position of the machine and displays a map with the number of passes made, taking into account the gaps and overlapping journeys. This shortens the time of execution of the works. It also enables the field crew to have direct access to the values of the material. Early detection of heterogeneity of the material layer, voids or hidden objects allows for their removal, re-leveling and rolling more quickly. The system was able to achieve the required compaction quicker, more accurately and without amendment.
Applying Trimble's machine control system to the construction of Kozanow's Wroclaw embankment allowed the contractor to shorten the length of the project and significantly reduce costs through accurate materials management.
Distribution and installation of Trimble machine control systems was provided by Trimtech Ltd., exclusive distributor of Trimble heavy civil construction. Trimtech Ltd. provides the tools and support to ensure the integration of data for the planning, design and positioning of construction, machine control and asset management throughout the lifecycle of construction projects.