METHOD FOR ASSESSING BEARING CAPACITY OF RAILWAY PILLARS

摘要

FIELD: physics.;SUBSTANCE: invention relates to methods of non-destructive testing, namely, acoustic methods, and can be used to assess the bearing capacity of reinforced concrete pillars. Method consists in the fact that a sensor for the conversion of acoustic emission (AE) signals is installed on the support at the boundary of the embedding of the support to the foundation, the vibrator is fixed on the support and subjected to support by vibration varying in frequency, the total energy of the AE is recorded, the results are entered into a personal computer under the support number, at subsequent stages of loading the supports with vibration, they control changes in the total energy of the AE, by the nature of the changes in the values of the total energy of the AE, the physical state of the support is judged and a decision is made to replace the support. On the border of embedding the support into the foundation, four metal pads with a thickness of 0.2–0.5 mm are glued on the four sides of the support, they are equipped with sensors for converting AE signals with magnetic holders, the vibrator is fixed at a height of 1.2–1.8 m, twice with an interval of at least 1.0 minutes, the support is loaded by vibration with a gradually varying frequency from 0 to 35 Hz. Next, a comparison is made of the values of the total energy of the AE from the first and second loadings of the support by vibration with the value of the critical level of the total energy of the AE obtained earlier, by statistical processing of a series of working supports of the same type, with defects, when loaded with vibration by a smoothly varying frequency from 0 to 35 Hz. If the obtained value of the total energy of the AE from the first time and the second time of loading the support with vibration exceeds the value of the critical total energy of the AE, and the ratio of the total energy of the AE, obtained from the first and second loadings of the support by vibration, is more than one unit by more than 10 %, this support is referred to as conditionally dangerous and the control decision is made with a frequency of 90–100 days. If during subsequent, at least four, control two-time loadings, the value of the total energy of the AE, obtained from the first time and the second time of loading the support with vibration, exceeds the value of the critical total energy of the AE and the ratio of the total energy of the AE obtained from the first and second loadings of the support by vibration shows each time the increase of this parameter compared to the previous indicator by more than 10 %, such supports are critically dangerous and decide to replace the support.;EFFECT: technical result consists in increasing the reliability of the information obtained when assessing the physical condition of a reinforced concrete support, which allows determining the critically dangerous support and its timely replacement.;1 cl, 1 dwg