Vibration measurements

Preventive measurements of the propagation of dynamic vibrations along with the preparation of an expert report and an indication of possible preventive actions.

 

If the construction site is adjacent to residential areas, construction works should be carried out in a way that causes minimal inconvenience to residents. One of the basic threats to the technical condition of buildings adjacent to the construction site and the people in them are mechanical vibrations emitted by working construction machines. Since the total time of vibration emission during the day generally exceeds 30 minutes, they should be treated as constantly occurring during individual phases of the construction process. Activities related to the reconstruction of the sewage network, the formation of embankments, the compaction of subgrade, the compaction of bituminous masses of the pavement, the strengthening of the soil, among others,

for bridge abutments, the construction of sheet piling, etc. are particularly burdensome The objects of special care should be various types of buildings and structures adjacent to the places of this type of work.
The technical condition of the buildings, the distance from the site of the works, local hydrogeological conditions but also the type and weight of the machines and equipment used, selected technologies for carrying out the works, etc. are important. Impacts related to the operation of road rollers, plate compactors, vibratory hammers, hydraulic hammers, etc. are particularly strong in terms of dynamics.

What must be done at the stage preceding the commencement of construction works is:

  • to make a descriptive and photographic inventory of buildings located in the construction works impact zone. The purpose of the inventory is to identify existing damage and defects in buildings and to indicate those whose current technical condition raises questions;
  • in the case of buildings located in heavily urbanised areas with significant vehicle traffic, it is justified to examine the existing dynamic background.
 
At the construction stage

In order to avoid claims, prior to the commencement of works emitting strong vibrations, it is imperative to conduct a trial study of the propagation of vibrations and their impact on the immediate environment. The testing results and the expert opinion developed on their basis will allow for the selection of work technology and vibration amplitude so that they are as minimally invasive as possible for neighboring buildings. Only such a course of action can prevent the occurrence or the increase in the extent of already existing damage. The adoption of vibration propagation testing as a basic preventive and diagnostic tool is also aimed at limiting to the minimum the necessary need for ongoing observation of existing and identified damage to buildings. The task of the supervisors is both to inform about the need and date of the tests as well as to
strictly comply with the selected parameters and the method of carrying out works for individual machines.

 

Legal bases for testing measurement and analysis results.

It is noted that foreign standards cannot be the basis for drawing conclusions from the analysis of the results of measurements of dynamic impacts. In relation to buildings, the main document is the PN- B-02170: 2016 standard.

 

The following standards are valid in Poland and relevant to the content of this compilation in the field of vibration monitoring:

  • PN- B-02170:2016 Assessment of the harmfulness of vibrations transmitted through the base surface to buildings;
  • PN-88/B-02171 Assessment of the impact of vibrations on people in buildings;
  • PN-82/N-01350 Vibration. Terminology.

In addition, only for comparative purposes it is possible to use foreign standards:

  • DIN 4150 Part 3 'Erschütterungen im Bauwesen – Einwirkungen auf bauliche Anlage';
  • DIN 45669 “Mechanical vibration and shock measurement” (trans.) “Messung von Schwingungsimmissionen”;
  • BS 7385-2 “Evaluation and measurement for vibration in buildings”;
  • Eurocode 3 - tab. 12.3.6.2. (not translated into Polish).