WSN in Prague metro

Martin Vaníček - CTU

WSN in Prague Metro Bologna 20 - 21 February 2008 Martin Vaníček

WSN installation in Prague - past

• Test site Near Dejvická metro station (~70m)

• 8 wireless nodes + Stargate gateway installed• 5 nodes + Stargate in one ring• 3 nodes along tunnel ~ 17m distance• Linksys GPRS router for internet access next to Stargate

• Last issues• Linksys router updated with new firmware to accept SMS for

connect status and reconnect to solve problems with connection dropping

• Stargate stopped working, the WSN removed during January visit (also by Cambridge team) – yesterday we found that power supply is faulty and not Stargate itself

WSN in Prague Metro Bologna 20 - 21 February 2008 Martin Vaníček

WSN installation in Prague - future

• Proposal:• WSN – will be installed in more locations (Nádraží Holešovice-

Vltavská, I.P.Pavlova-Vyšehrad & Staroměstská-Můstek ?), where real measurements will be done, in a setup proposed from test location

• WSN will be connected to real devices for monitoring –inclinometers (developed in Cambridge) and Geokoncrackmeters in order to start collecting measured data

• Internet – Linksys / Stargate will be installed closer to the station (not more then 50m)

• The real installation will be done after testing period at the lab, where all necessary implementations for periodic data transfer from tunnel and process for remote management restart will be done

WSN in Prague Metro Bologna 20 - 21 February 2008 Martin Vaníček

WSN installation in Prague – future 2 (based on yesterday‘s meeting)

• Proposal:• WSN – setup by Cambridge (Balloon gateway with X-mesh

wireless data collection and communication protocol) will be installed on 1 real location in Prague

• WSN using Crossbow‘s implementation (Stargate Netbridgegateway with X-mesh protocol) will be installed on other real location (s) in Prague Metro

• Close co-operation between Cambridge and Prague teams on the X-mesh protocol implementation to be compatible and therefore comparable

• Unless required, the old system using Stargate and Surge protocol will not be installed in Prague, as the system become recently obsolete

Thank you

for your attention

Prague Metro MonitoringSection in km 18,725

Bologna Meeting – 02/2008Jan Záleský

Placement of tilt plates and convergence bolts

Initial inclination of tilt plates

• Axe of 2.1 - 2.4 to horizontal plane

• 2.05 plate to horizontal plane

Yellow points –convergence bolts25,4°

C 04,4°L 00,6°

09,8°

47,6°51,7°

Test area

All results of tilt measurement

-1,50

-1,00

-0,50

0,00

0,50

1,00

1.12.2006 1.2.2007 1.4.2007 1.6.2007 1.8.2007 1.10.2007 1.12.2007 1.2.2008

-30,0

-25,0

-20,0

-15,0

-10,0

-5,0

0,0

5,0

10,0

15,0

20,0

2.01 [mm/m] 2.02 [mm/m] 2.03 [mm/m] 2.04 [mm/m]2.05_C [mm/m] 2.05_L [mm/m] Temp. in deg.C

Left / Right of the Rail

-1,00

-0,80

-0,60

-0,40

-0,20

0,00

0,20

0,40

1.12.2006 1.2.2007 1.4.2007 1.6.2007 1.8.2007 1.10.2007 1.12.2007 1.2.2008

-30,0

-25,0

-20,0

-15,0

-10,0

-5,0

0,0

5,0

10,0

15,0

20,0

2.01 [mm/m] 2.04 [mm/m] Temp. in deg.C

Left / Right of the Tunnel Crown

-0,80

-0,60

-0,40

-0,20

0,00

0,20

0,40

0,60

0,80

1,00

1.12.2006 1.2.2007 1.4.2007 1.6.2007 1.8.2007 1.10.2007 1.12.2007 1.2.2008

-30,0

-25,0

-20,0

-15,0

-10,0

-5,0

0,0

5,0

10,0

15,0

20,0

2.02 [mm/m] 2.03 [mm/m] Temp. in deg.C

Plate at Bottom of the Tunnel

-1,50

-1,00

-0,50

0,00

0,50

1,00

1.12.2006 1.2.2007 1.4.2007 1.6.2007 1.8.2007 1.10.2007 1.12.2007 1.2.2008

-30,0

-25,0

-20,0

-15,0

-10,0

-5,0

0,0

5,0

10,0

15,0

20,0

2.05_C [mm/m] 2.05_L [mm/m] Temp. in deg.C

Convergence monitoring

Started:• “Z” reading

17/01/08 • 1st reading

08/02/08

No signifacantchanges

RESEARCH ONUNDERGROUND STRUCTURES AGEING

WITH EXPLOITATION OF MONITORINGAND MICROMEASUREMENT SYSTEMS -

AUXILIARY METHODS II

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

Czech Technical University in Prague

Grant Agency of Czech Republic, Reg. Nr. 103/06/1257:

Research of underground structures ageing with exploitation of monitoring and micro-measurement systems

AUXILIARY METHODS II - GA CR Reg. Nr. 103/06/1257:

a) monitoring of time-development of selected lining parts dyna-mic behaviour changes under traffic loads (at monitoring profile on line C, rail Nr.2, kilometer spacing 18,725 of the Prague metro, near the Holesovice Station) - systematically performed,

b) recording and processing of dynamic response accelerograms of reinforced concrete slab during the laboratory fatigue test (finished, data in processing),

c) monitoring of fatigue failure time-development by means of examination of elastic waves spreading parameters (up to now not started because of procceding instalations, it will start next month).

a) MONITORING OF TIME-DEVELOPMENT

CHANGES OF SELECTED LINING PARTS DYNAMIC

BEHAVIOUR UNDER TRAFFIC LOADS

at monitoring profile on line C, rail Nr.2, kilometer

spacing 18,725 of the Prague metro, near the

Holesovice Station.

LEVEL DISTRIBUTION GRAPHS OF NORMED DEFLECTION VALUES

in channel A - (defective part) in channel B - (intact part)

(values in channel A - values in channel B)

DATA ANALYSIS / TIME DOMAIN / DESCRIPTIVE STATISTICS

Y = nu

mber o

f day

s sinc

e 1.1.20

07

X = normed deflection (100*j)

Z =

val

ue fr

eque

ncy

(n)

Time development of level distribution of normed deflections in channel A

with coloured differences (A-B)

number of days since 1.1.2007normed deflection (j)

num

ber

of v

alue

s (n)

DATA ANALYSIS / TIME DOMAIN / DESCRIPTIVE STATISTICS

Freq

uenc

y di

strib

utio

n of

def

lect

ions

in c

hann

el B

Frequency distribution of deflections in channel A

Col

o ur i

n g r

efl e

c ts t

he n

u mbe

r o f

day

s si

nce

1.1.

2 00 7

DATA ANALYSIS/ TIME DOMAIN / DESCRIPTIVE STATISTICSTime development of level distribution

of normed deflections in channel A and Bwith coloured measuring stage

A ~ B in level distribution

0

50

100

150

200

250

300

350

400

450

500

0 50 100 150 200 250 300 350 400 450 500

number of values of deflection in channel A

num

ber o

f val

ues

of d

efle

ctio

n in

cha

nnel

BDATA ANALYSIS / TIME DOMAIN / DESCRIPTIVE STATISTICS

A ~ (A-B) in level distribution

0

100

200

300

400

500

600

0 50 100 150 200 250 300 350 400 450 500

number of values of deflection in channel A

num

ber o

f val

ues

(A-B

)DATA ANALYSIS / TIME DOMAIN / DESCRIPTIVE STATISTICS

0,00

0,05

0,10

0,15

0,20

0,25

0,30

0 20 40 60 80 100 120

frequency (Hz)

Am

pl.-P

eak

(j)

FFT(A) FFT(B)

FFT of channel A and B normed deflections time sectionDATA ANALYSIS FREQUENCY DOMAIN

DATA ANALYSIS FREQUENCY DOMAIN

num

ber o

f day

s sin

ce1.

1.20

07

num

ber o

f day

s sin

ce1.

1.20

07

Time development of normed deflections FFT in channel A and B

frequency (Hz) frequency (Hz)

Geophone A (defective part)

Geophone B (intact part)

DATA ANALYSIS FREQUENCY DOMAIN

numbe

r of d

ays s

ince 1.1

.2007

Time development of differential FFT amplitudes - FFT of (A - B) isochronal deflections

frequency (Hz)

DATA ANALYSIS FREQUENCY DOMAIN

number of days since 1.1.2007

frequency (Hz)

Time development of differential FFT amplitudes - FFT of (A - B) isochronal deflections

(detail for 5 - 25 Hz frequency band)

DATA ANALYSIS FREQUENCY DOMAIN

number of

days s

ince1.1

.2007

Time development of FFT amplitude differences {(FFT in channel A) - (FFT in channel B)}

frequency (Hz)

DATA ANALYSIS FREQUENCY DOMAIN

norm

ed am

plitud

es of

FFT

in ch

anne

l A

(defe

ctive

part)normed amplitudes of FFT in channel B

(intact part)

Z = differences of normed amplitudes (A - B)

DATA ANALYSIS FREQUENCY DOMAIN

norm

ed am

plitu

des o

f FFT

in ch

anne

l A

(defe

ctive

part)

normed amplitudes of FFT in channel B

(intact part)

Z = differences of {FFT(A) - FFT(B)}

INTEGRAL OF NORMED DEFLECTION TIME SECTION FFT (frequency band 5 - 25 Hz]

-2

0

2

4

6

8

10

12

14

40 90 140 190 240 290 340 390

count of days from 1. 1. 2007 to 17.1.2008

I(FFT

)

I(A) I(B) IFFT(A-B) I(FFTA-FFTB) temperature in tunnel (°C/2)Fe

b 20

07

Mar

200

7

Apr

200

7

May

200

7

Jun

2 007

Jul 2

007

Aug

200

7

Sep

2007

Oct

200

7

Nov

200

7

Dec

200

7

Jan

2008

INTEGRAL OF NORMED DEFLECTION TIME SECTION FFT (frequency band 5 - 25 Hz]

6,0

6,5

7,0

7,5

8,0

8,5

40 90 140 190 240 290 340 390

count of days from 1. 1. 2007 to 17.1.2008

I(FFT

)I(A) I(B) IFFT(A-B)

Feb

2007

Mar

200

7

Apr

200

7

May

200

7

Jun

2 007

Jul 2

007

Aug

200

7

Sep

2007

Oct

200

7

Nov

200

7

Dec

200

7

Jan

2008

b) DYNAMIC RESPONSE OF THE REINFORCED CONCRETE SLAB ON

LABORATORY FATIGUE TEST

The tested slab in the fatigue test bench.

PHASE RELATIONS

velocity

accelerograms

deflections

harmonic

PHASE RELATIONS - LOADING AREA

PHASE RELATIONS - RELAXATION AREA

accelerograms

velocity

deflections

harmonic

c) MONITORING OF FATIGUE FAILURE

TIME-DEVELOPMENT BY MEANS OF

EXAMINATION OF ELASTIC WAVES

SPREADING PARAMETERS

- measuring will start after finishing all

intended instalations in the acoustic sampling

field.

Metro Prague

Svatoslav Chamra

Measuring standpoints

km 19,435 – km 19,480

Line AMůstek ‐ Staroměstská

Section fit for instrumentation ‐somewhere between km 19,435 – 19,480– compressed concrete lining by soviet mechanized tunnelling shield TSCB‐3

Prague fault ‐ about km 19,450, cca 20 m width

tectonic deformationof clay shales –zahoranske &bohdalecke &dobrotivske layers

boundary‐line aboutkm 19,463

Geological conditions

Various types of cracks

April 2003

October 2007

April 2003 October 2007

Degradation of  compressed concrete tunnel lining by aggressive water

Thank you for your attention.

Nuselský bridge

Facts• one of the biggest in the CR• built 1965 – 1973• 6 lane road, twin track metro,

walkway• 485m long, 26,5m wide,

42,5m high• pre-stressed reinforced

concrete frame on 4 pillars• 1997 – repair of the steel grid

due to fatigue cracks

Metro line C

42,5

m

Proposed instrumentation

• Tilt plates• VW crackmeters• Tape extensometer• Geophysical methods

Installation in London UndergroundPeter Bennett

• Background– Spalling in deep tunnel– Fresh and historical

Damaged area• Covers over 130m• 54 joints identified

– Currently monitoring some with VWSG

• Caused by joint movement

• Possibly tension cracks on wall?

VWSG Monitoring

Proposal• Install• 16 tiltmeters

– B,F,H,M, 1640,1661,1689,1714

• 5 crackmeters– Joint F-G,

1640,1661,1689,1714– Crack in segment K at 1640

• 2 relays / environmental monitors– L, 1675 and 1607

• 1 gateway– B, 1685

• Anemometer and accelerometers– Into data logger– 24hrs monitoring in each of

three locations

Gateway

• Ethernet gateway in tunnel• GPRS connection at top of shaft• Remotely powered gateway and repeater

hubs