G A f C h R bl R N / / 6Grant Agency of Czech Republic, Reg. Nr. 103/09/1600:

RESEARCH OF THE MONITORING METHODS OFRESEARCH OF THE MONITORING METHODS OF MICRO-DEFORMATIONS OF UNDERGROUND

(METRO) STUCTURES( )2009 - 2011

Proposer: Prof Ing Ivan Vanicek DrScProposer: Prof. Ing. Ivan Vanicek, DrSc.Author of the report: RNDr. Jaromir Machacek, Ph.D.

Czech Technical University in Prague

MONITORING OF TIME-

DEVELOPMENT CHANGES OF

DYNAMIC BEHAVIOR OF

SELECTED LINING PART UNDER

TRAFFIC LOADSTRAFFIC LOADS

at monitoring profile on line A, rail

N chainage 6 f hNr.1, chainage 19,467 of the Prague metro, near the MUSTEK

Station.

RESEARCH OF THE MONITORING METHODS OF MICRO-DEFORMATIONS OF UNDERGROUND (METRO) STUCTURES 2009 - 2011

a) the monitoring profile was situated into area of crossing "Prague fault" geological structurefault geological structure

b) type of measurements: dynamic response of tunnel lining part to traffic loads traffic loads

c) data acquisition conditions: two electrodynamic (velocity) sensors ( h ) d bl f b 1 0 f l h di i l (geophones), data cable of about 170 m of length, digital storage oscilloscope (DSO) FLUKE type 192, sample frequency 2,5 kHz, 27500 samples per record record length 11 s27500 samples per record, record length 11 s,

d) time period of monitoring: from 15.12.2008 to 3.11.2009 and from 19 2 2010 dynamic monitoring goes on againand from 19.2.2010 dynamic monitoring goes on again

e) data acquisition frequency: once a month

f) evaluated parameter of response: sum of absolute values of particle velocity

RESEARCH OF THE MONITORING METHODS OF MICRO-DEFORMATIONS OF UNDERGROUND (METRO) STUCTURES 2009 - 2011

Results are significantly determined (excluding deformations and ageing) particularly byageing) particularly by

1. induced noise (which especially generate signaling),

2. tunnel climate (inner temperature, relative humidity and air pressure),

3. speed of the train unit motion,

4 instant mass of an individual carriage of train units4. instant mass of an individual carriage of train units,

5. current technical condition of an individual carriage of train units,

6. current technical condition of the track structure and rail geometry

etcetc.

Secondary outputs ofSecondary outputs of monitoring based on the

analysis of exciting forces:y gMONITORING OF

TECHNICAL CONDITIONS OF

TRAIN UNITS, RAILS AND TRACK

STRUCTURES

1. The sum of absolute values of particle velocity is one of the most useful parame-CONCLUSIONS:

p y pters (among dynamic characteristics) for evaluation of ageing manifestation. It is in good accordance with energetic aspects.

2 Th f th d f ti t f it d t d t t t 2. The response of the defective part of monitored segment does not react to temperature changes. Defective part is probably not in adequate contact with the rock massif behind the lining.

3. The influence of climatic changes in tunnel on the data collected is not only connected with response of material properties (absorption and dissipation of

l ti ) diff t h i l diti It i b d d bt th t th elastic waves) on different physical conditions. It is beyond doubt that these climatic changes generate space deformations of tunnel lining, in some measure, too.

4. The response of the defective part of monitored segment indicate deformations of tunnel lining in period from July to September 2009. Tightening of monitored crack or closing of defective part to rock massif (and/or accompanied with encrustation of or closing of defective part to rock massif (and/or accompanied with encrustation of crack with carbonaceous filling) occurs in that period.

5. The analysis of exciting forces can be exploited for monitoring of current technical 5. The analysis of exciting forces can be exploited for monitoring of current technical condition of an individual carriage (especially rail undercarriages) of train units, current technical condition of the track structure and rail geometry.

• Thank You for Your attention.