Case studies

In 2021 and 2023 we organized 2 cycles of webinars, attended online by more than 300 professionals and researchers from all around the world:

• SOIL SERIES
  • H, V, H/V (entry-level)  – program
  • H/V – FOCUS ON Vs (intermediate level 1) – program
  • JOINT FIT OF H/V, DISPERSION CURVES AND OTHER DATA: EXERCISE SESSION (intermediate level 2) – program
  • H/V and Vs CONTOUR (addendum) – program

• STRUCTURAL SERIES
  • Experimental dynamic characterization of structures (entry-level) – program

These courses, together with the course materials and the self-assessment test, can now be purchased. To register and purchase access to the recording of one or more events, fill out this form.

Click here for an overview of the courses and the participants’ feedback. Feel free to ask for more information!

“This was very well done, starting basic and getting progressively more difficult. A lot of information was presented. I would be interested in a second webinar focused on stratigraphic modelling.”

“Excellent content and informative webinar.”

“Terrific webinar! I learned a great deal. I’m a beginner, and the detailed information was presented at a good pace and in a way that I was able to follow. If possible, I’d like to be involved in an additional Vs or HVSR webinar. Thank you.”

“Very informative webinar. The instructor discussed all the key topics. I would be interested in the future webinar”

Every week on LinkedIn we publish news, curiosities, information about applications of our instruments and software worldwide and in different fields (geophysics, structural engineering, sports etc.). Follow us on LinkedIn to collect new ideas for your work!

A summary of the LinkedIn posts published in 2022 is given in the newsletter attached here below.

MoHo has recently participated in the PHYTO.PERC. project cofunded by Regione del Veneto (POR FESR 2014-2020 ASSE 1 “RICERCA, SVILUPPO TECNOLOGICO E INNOVAZIONE” AZIONE 1.1.4 “Sostegno alle attività collaborative di R&S per lo sviluppo di nuove tecnologie sostenibili, di nuovi prodotti e servizi” DGR n. 711 del 28 maggio 2019), in cooperation with Fondazione Università Ca’ Foscari (Venice), Geo.Ti.La. srl, Progeco Ambiente spa, desam ingegneria e ambiente . Within the frame of the project, MoHo has designed and produced an innovative version of Electra Matrix, specifically conceived for permanent or long-term installations in waste landfill areas.

This new device is capable to continously monitor the electrical resistivity and spontaneous potentials of waste landfills and their evolution, which depends also on the methanogenic bacterial activty.
Monitoring such electrical parameters allows one to discover where gases accumulate and the variation of such cumuli as a function of external parameters (temperature, water content etc.), thus permitting a more effective biogas management, extraction and exploitation, and with a clear reduction on the environmental impact of waste landfills.

In parallel, the Fondazione Università Ca’ Foscari has exploited the electrical data acquired on small scale models of landills to the aim of assessing the most suitable vegetable species to be used as phytoremediators. This work has been presented at the Ecomondo 2021 exhibition and is summarized at the link below.

We periodically publish short notes on Ingenio-Web with ideas about possible applications of our instruments. Click the links below for the English translation!

Under operational conditions, two types of vibrations are relevant in civil engineering:

1. Vibrations that cause nuisance to people,
2. Vibrations that can induce (cosmetic) damage to structures.

Many different regulations exist in the world to assess the acceptable threshold limits in both cases and under different circumstances (e.g. UNI 9614 for human exposure to vibrations in buildings; ISO/TC108/SC2 regarding the habitability on passenger and merchant ships, UNI EN 1990 assessing the comfort criteria on pedestrian bridges; UNI 9916, ISO 4866, DIN 4150, BS 7385 assessing the vibration levels potentially damaging structures).

The evaluation of human exposure to vibrations is usually performed by filtering the acquired signals (usually accelerations) to reproduce the spectrum of human sensitivity to vibrations. The filtered and weighted signals are then treated to get statistically significant information.

The assessment of vibration levels potentially damaging structures are more frequently performed in terms of velocity of vibration, to recall the amount of kinetic energy transmitted to the structure. In this evaluation, the duration of the vibration (classified as short or long compared to the structure natural-frequency) can be more important than the peak amplitude values.

At MoHo we give specialistic courses on these themes, with case studies and practical exercises. All these vibration monitoring and analysis can be explored with Tromino^® and Suricat.

The concept of “Structural Health Monitoring” is often associated to the installation of sensors, continuously sending data about a structure. These include the amplitude of vibrations, the eigen-frequencies, displacements, deformations etc. and can be acquired by mechanical, electro-mechanical, optical, electromagnetic sensors, put in contact with the structure or even kept at distance.

However, the different parameters that can be recorded on a structure vary over time in response to external factors that many times have nothing to do with the health condition of the structure.

The variations of mass and stiffness associated to seismic retrofit induce changes in the modal response of a structure and  thus in the design response spectrum, which is generally the expected result of those interventions.

Less known is probably the fact that both diurnal and seasonal temperature fluctuations have non negligible effects on the modal frequencies (figure on the left).

In the case of dams, the effect of the water level on the modal frequencies is intuitively large. However, this effect is not small also on smaller structures, such as bridges with submerged pillars and sea (or river) embankments, subjected to tidal variations.

The variation of the modal frequencies and damping of a structure over time is therefore a physiological event, within some limits that must be precisely assessed to interpret the monitoring data in a significant way.

Such variations have to be known or accounted for also when the measurements on the structure are not continuous over time.

These variations condition the number of significant digits that can be associated to any experimental analysis. Assessing the uncertainty of a measurement is a compulsory step in any measurement process and is the only informative way of transferring an information in the present world where the excess of information sometime turns into a loss of clarity.

Specialistic courses on these themes are now available online at MoHo! You can experiment discontinuous monitoring or continous monitoring of structures with MoHo.

During the last AEGC 2019, our exclusive Australian representative, Resource Potentials, was awarded for the best ‘Minerals’ and best ‘Environment/Engineering’ paper.

Some of these papers can be downloaded below.

Measuring the dynamic behavior of a structure is a mandatory step in the tuning and validation phase of any numerical model. However, the ways in which this experimental assessment is undertaken are many and not all fruitful. In this paper the authors briefly review the basic principles of the dynamic characterization of bridges and the most common acquisition practices that can lead to wrong conclusions, through a set of examples.

Matera, European capital of Culture 2019. Tromino^® contributed to the pride of the town: It was employed for the dynamic characterization of some bridges, built for the occasion.

Tromino^® has been using for several years in the experimental modal analysis of hundreds of structures in the whole world. Ask us for some examples…

The MoHo training course activity on surface-wave seismic techniques continues also abroad. Here is the calendar.