Measuring force and impedance for the tapping machine

The standard tapping machine used for the ASTM and ISO tests does not require the test engineer to measure the input force in the system, instead, just relies on measuring the sound pressure level (SPL) output. However, the input force depends on the assembly itself being tested. The input force levels are lower for lightweight assemblies like hardwood floors as compared to heavyweight assemblies like concrete. Without knowledge of this input force, the output SPL levels cannot and should not be compared using the IIC (Impact Insulation Class) rating. In this work, we measured the input force levels for the same tapping machine on different floors. We also measured the floor impedance for different assemblies and their comparison is also shown. This work shows the importance of measuring input forces for the standard floor-ceiling assembly impact tests

Laboratory tests results of a measuring station for plate bearing tests of road structures

An article devoted to the development of the latest equipment for testing road structures during the diagnostics of roads both in the process of repair and construction, and in the process of operation. A measuring station for stamp tests of road structures and their layers has been developed, which unites the test equipment into a single automated complex mounted on the base car. This eliminates the need for manual labor of the operator, increases productivity and accuracy of tests, provides the ability to perform multiple loads. At the same time, any truck or road vehicle can be used to create the load. A measuring unit with special software installed on it is used for registration and processing of measurement results. The results of laboratory tests of the measuring station, which were carried out in the laboratory of the department of metrological support of measurements of geometric quantities of SE «Ukrmetrteststandard» are highlighted. The obtained results indicate that the values of measuring force, absolute error and range of measurements of the station of movement of the station meet the regulatory requirements.

Design, Manufacture and Testing of a S Type Force Transducer

This paper presents the methodology of designing a transducer for the experimental measurement of forces. For this purpose, an elastic element of the shape of the letter "S" is designed and manufactured. The elastic element designed in SolidWorks is subjected to virtual testing, using the finite element method in ANSYS. After validating the results obtained considering the maximum values ​​of the stresses that appear for the nominal load, the experimental model of the transducer is realized. The central part of the elastic element behaves like a fixed double beam subjected to bend by the measuring force. On this beam are bonded strain gauge transducers, which measure the deformations produced by bending. The transducer is calibrated, in order to obtain the calibration constant, based on the obtained characteristic, that is, the dependence of the specific strain-deformation and force. The transducer thus constructed can be used in force measurement applications.

Development of a Microprobing System for Side Wall Detection Based on Local Surface Interaction Force Detection

This study proposes a novel microprobing system for the surface detection of the side wall of micrometric scale workpieces based on the detection of the local surface interaction force. A spherical tip-shaped glass capillary tube with a micrometric scale diameter was employed as a micro-stylus. To obtain a low measuring force, the local attractive interaction force on the surface of the workpieces was detected by the vibrating micro-stylus and used as the probing trigger signal. The vibration in the main axis direction of the stylus allowed detection of the local surface interaction force in all directions around the stylus shaft. In this paper, the principle and configuration of the developed microprobe are mentioned. Probing detections around the stylus shaft were verified by the surface detection of a pin gauge. Repeatability of the probing by the developed microprobing system was evaluated.

WAVES LOAD ACTING ON MODULAR FLOATING PONTOON GUIDED BY PILES PLACED ON THE FRONT OF VERTICAL WALL

Experimental Station for Coastal developed a pilot project of modular concrete floating structure that served as a quay at Kalibaru in North Jakarta. The structure guided by piles and placed in front of Jakarta Coastal Dyke which is a vertical wall structure. From evaluating the structure performance, it is found that the strength of the pile is an important factor for service life of the structure. To provide this, a physical model test of the floating pontoon module guided by piles was conducted at the Laboratory of Balai Litbang Pantai. The model used to determine the behavior of the structure and loads that must be hold by the pile as a seakeeping mechanism. It is done by measuring force acting on piles that caused by pontoon impact by using load cells. The pontoon loaded by regular and irregular waves. From the tests result, the recorded forces has an impuls pattern which have maximum value of 112.67 N. The load that occurs on the pile was not spread evenly on the four piles that hold the floating module. The disrepancy are around 2 – 40%. The forces acting on piles depends on the ponton distance to the vertical wall. The forces increases along with the increases of relative distances of structure to vertical wall to the wavelength. The presence of vertical vall caused this increase because it amplify the waves acting on the structure. The amplification effect are the greatest when the structure distrance from the wall is the multiplication factor of halves of wavelength.Keywords : physical model test, pontoon, floating quay, pile guide, impact force