TEM Journal. Volume 11, Issue 3, pages 1002-1006, ISSN 2217-8309, DOI: 10.18421/TEM113-02, August 2022. 1002 TEM Journal – Volume 11 / Number 3 / 2022. Methodology for Measuring the Impact Force of Compaction Rammers Aleksandar Ivanov, Mihaela Ivanova, Tsvetelina Georgieva University of Ruse, st. Studentska 8, Ruse, Bulgaria Abstract – In this paper a methodology to measure impact force is proposed. It includes conceptual description of the sequence of the steps, tools needed to carry out the measurement, validation and the post processing of the collected data and automated data acquisition during end-of-line testing. The proposed concept is also putting requirements to the needed equipment. Keywords – Impact force, compaction machine, rammer, high-speed camera, measurement, guaranteed value. 1. Introduction In this paper a methodology to measure impact force is proposed. It includes conceptual description of the sequence of the steps, tools needed to carry out the measurement, validation and the post processing of the collected data and automated data acquisition during end-of-line testing. The proposed concept is also putting requirements to the needed equipment. Compaction machines (rammers, forward compaction plates, reversible compaction plates and rollers) are used in the construction business to compact and smoot ground materials such as soil, gravel, asphalt, sand, and etc. DOI: 10.18421/TEM113-02 https://doi.org/10.18421/TEM113-02 Corresponding author: Aleksandar Ivanov, University of Ruse, st. Studentska 8, Ruse, Bulgaria. Email: akivanov@uni‐ruse.bg Received: 26 May 2022. Revised: 18 July 2022. Accepted: 25 July 2022. Published: 29 August 2022. © 2022 Aleksandar Ivanov, Mihaela Ivanova & Tsvetelina Georgieva; published by UIKTEN. This work is licensed under the Creative Commons Attribution‐ NonCommercial‐NoDerivs 4.0 License. The article is published with Open Access at https://www.temjournal.com/ Compaction machines have many characteristics but their performance can be measured by how much the machine compacts the ground material and how fast it does it therefore, this is really valuable information for customers. Controversially for most compaction machines, the presented characteristic is the centrifugal force which means that the main component of the machine is the rotating eccentric mass. The issue here is that the centrifugal force is not fully defining the performance of the machine regarding compaction capability. Centrifuge modeling [1] is a widely introduced method to measure soil stiffness. That type of models use the acceleration of the drum is used as input to determine the stiffness. However, there are machines which do not use eccentric mass components, such as rammers. In this case, the centrifugal force cannot be provided as a machine characteristic which is confusing for the customers. Furthermore, those systems using the centrifuge model are too expensive for the comparatively cheap rammer type of compaction machines. There were previously researches if it is feasible to use that technology on rammer type of machine, but researchers report that it cannot be used for high frequency machines [2]. For all types of compaction machines, one of the main representative characteristics is the impact force they provide. Analytical calculations of this characteristic are not very well known because of the complexity of the machines. In reality, it is much more accurate to measure the eccentric force of the machines. A reference in the literature for such suitable methodology for real end-of-line industrial measurements has not been found. Such methodology will be very useful to compare the performance of different machines in same conditions. Furthermore, such characteristics which are descriptive of the done compaction work are not followed and not presented in the relevant product standards for rammers and plate type of construction machines EN 500-1 [3] and EN 500-4 [4]. Other characteristics are made mandatory to be followed but they are not referring to the effectivity or the efficiency of the work the machine has performed. Nowadays is also important to take into