Geotechnical monitoring of gravitational natural hazards
Huggenberger AG was commissioned in 2018 and 2019 to install and operate systems for monitoring gravitational natural hazards. A selection of these projects and the system components used are described below. In all these projects, radio sensor networks were used, which are characterized by large radio ranges, even in difficult terrain and long autonomy in battery operation.
Huggenberger-Monitor: Data Management for Monitoring Projects on the Internet
With the Huggenberger Monitor, measurement results from various data loggers, including those from the WRLog system radio data network and the Huggenberger tensologger, are displayed on an Internet project website. This gives users very easy-to-use and password-protected access to the measurement results, their metadata and important additional project information.
Anchor load measurement with Huggenberger load cells. Wireless data transmission and web data management
Anchor load measurements for construction pits, support structures, rock wall protection and for other geotechnical structures are, within the safety and operation plan, an essential part of risk control in construction. Anchor load cells are often supplied and installed by the anchor supplier. The specialist company, commissioned with the anchoring work, is often responsible also to carry out the measurements, to evaluate the results and to transmit these to the client and the engineers responsible for the project.
Lesotho, Katse Dam
The Katse Dam, constructed during the first phase of the Lesotho Highlands Water Project, is a 185m high double arch concrete dam with a crest length of 710m. The geological formation of the Katse dam area is characterized by the existence of almost entirely basaltic, nearly sub horizontal, lavas flow deposits. The main discontinuities are composed of sub horizontal shear zones and flow contacts, layers of basalt and some sub vertical stress relief joints.
After main construction work was completed, a set of direct and inverted pendulums, partially equipped with manual operated and partially with automatic pendulum measuring devices not originating from Huggenberger AG, has been installed. Early 2018, Huggenberger AG supplied and instaled 10 telelot units of the type VDD3V4 to refurbish the old monitoring system.
Weggis K2B Horlaui
In June 2018 Huggenberger AG was appointed to refurbish an existing system to monitor the Horlaui-rockcliff in Weggis, Switzerland with ne additional sensors, data loggers and data transmission. After installation this rock cliff was stabilized and partially rock formations have been excavated. The monitoring played an important part to analyze stability and for decision making of the construction work to decide what parts can remain and what parts of the cliff have to be demolished or anchored.
Concrete dam Maigrauge, ZSL and ZS-Systems
The small gravity concrete dam, constructed 150 years ago in Fribourg, Switzerland, was increased in height to 21m and has a crest length of 113.5m. The dam, operated by Groupe E (Broc, Schwitzerland) is equipped with different Huggenberger-monitoring systems.
Due to the fact, that the dam has no inspection gallery and the foundation is on weathered Molasse type rock, special systems have been installed and monitor the dams behavoir since many years accurate and reliable.