Automated Tunnel Monitoring System (ATMS)

Remote Wire-less Automatic

Tunnel Monitoring System

SysEng (S) Pte Ltd

Wisescan Engineering

Pte Ltd

Siber Hegner South East

Asia Pte Ltd

GeoEng Consultants

Deploying Remote Wire-less

Automatic Tunnel Monitoring System

to reduce the risks of uncertainties

By Dr G H Tan

This presentation describes the Automatic

Tunnel Monitoring System used for the

Construction of Newton Life Church

The consortium comprises of

SysEng (System Designer for the Automatic

Wire-less and Internet Monitoring System)

Siber Hagner (Leica Geosystem Instrument

Integrator)

Wisescan Engineering (Tunnel Surveyor)

GeoEng (Geotechnical Specialist)

• Started in 1994

• Specializes in Test & Measurement

• Signal Analysis and Digital Signal

Processing Techniques Wireless Data

Acquisition Systems

• Structural Instrumentation for Buildings,

Tunnels, Highway bridges

• Vibration and Acoustic Measurement

Systems.

• Machine Vision Inspection Systems

SysEng (S) Pte Ltd


Services Pte Ltd • Founded in 1992 and awarded ISO 9002 1997

• General Engineering survey

• MRT Tunneling Survey

• Tunnel Deformation and Monitoring Survey

• Ground Settlement Movement Study Survey

• Hydrographic Survey

• Cable and Gas pipe as-built survey and

production of drawing in GIS format

Siber Hagner South East

Asia Pte Ltd• Regional representative for Leica Geosystems

covering Malaysia and Singapore

• Support Leica Geosystems Software with local

customization

• 1st Tunnel Monitoring System carried out for

Bugis Junction in Singapore 10 years ago

GeoEng Consultants

Specialist Civil and Geotechnical

Consulting Engineers

•Temporary Retaining Systems

•Soil Improvement

•Underground Support Systems

•Foundation Systems

•Underpinning of Buildings

•Basement Design

•Trenchless Technology

Structural Health Monitoring Systems

• Republic Plaza Building (280 m) since 1995

• OUB Building (280 m)

• Toa Payoh 25 storey HDB Building

• Tuas 2nd Link Bridge since 1996

• Kranji Expressway LTA C3623

• North East Tower in Hong Kong (420 m)

• Changi Airport Car Park Terminal 2 LTA C504

• Pasir Panjang Semi-Expressway C3223 since

2002

• Bukit Timah Expressway C3222 since 2002

Automatic Tunnel Monitoring Systems

• Changi Airport Runway 1 Monitoring LTA

C5342

• Circle Line LTA C825 North & South Bound

• SMU site

• Church Street Building

• Circle Line LTA C825 East & West Bound

• Harbor Front LTA C859

• Newton Life Church

• National Library Board

• Deep Tunnel Sewage PUB T06

Potential Population

growth in Cities

• Monitors adjacent buildings when an old

building is being tore down and rebuild to a

higher building

• Monitor piling and soil movements do not

affect existing structures

• Population will grow in ASEAN, China, India

• Cities will increase in densities

• Demand for transportation in cities will rise

with Highways and Tunnels

• Infra structures have to be upgraded

Monitoring to minimize risks

Typical Challenges face

by Construction

Industry as reported in

Straits Times, showing

Damages & Disruptions

to Infrastructures and

Assets

Tunnelling affects Buildings

Tunnelling affects Roads

Tunnelling affects Roads

Construction Damages

surrounding houses

Construction of Building affects

adjacent Property Value

Recent Headline

case in a Famous

Landmark in

Singapore

Soil Conditions affecting

Construction

Automatic Tunnel Monitoring

Developed for Infra structure and

Asset Protection• Longer underground networks and crossing

each other

• High density buildings near underground

stations due to popularity and convenience

• Other underground networks like Deep

Tunnel Sewage, Power Utilities, Water, Gas,

Telecommunication

• Expensive to repair underground if damage

Consequences of late awareness

in Structure & Soil movements

• Loss of lives (Like Hotel New World)

• Unwanted publicity in Newspapers

• Delays in completion of projects causing

cash flow problems

• Show poor performance of company

• Legal and Financial consequences for

damaging assets

• Losing future potential businesses

To achieve a robust &

reliable monitoring

system, the technologies

deployed must be reliable

and have local technical

support to ensure high

system up time for the

clients

eMonitoring

Technologyby

SysEng (S) Pte Ltd

eMonitoring

is

Remote Monitoring

using

Wire-less

technology on

the Internet

What is eMonitoring ?

• Wire-less for data communication by riding

on the open public mobile phone infra-

structure to give REAL TIME ALERT to

multiple users

• Internet monitoring for automatic data

collection and monitoring at a central server

• The customer to receive the data via

the Internet making the information

available to more users .. faster

Outdoor Inspection

Monitoring

Street Light

Monitoring

Tunnel Monitoring

Water Level

Monitoring

Geotechnical

Monitoring

The RTU takes a

photo of floodgate

when it opens or

close.Internet

Users

There are diff. type of

devices to access the

application services through

diff. protocol.

Web

Server

GPRS/

GSM

Gateway

Supervisory

Monitoring

Overview of eMs Application

The Leica’s instrument

scan the reading by

prism installed at

tunnel and the RTU will

send the reading back

to eMs Server.

The street light

located at

crowded area,

like shopping

centre, school

and tourist

spot become

important and

crucial at night.

When the light bulb spoilt, the

RTU control unit in the street

lights will alert the users and

report to server.

The RTU will have

the function of taking

photos, GPR, Times

Stamps, and memory

for the storage

information. This

information can be

sent to server

through wireless

network. It is kind of

outdoors surveillance

systems.

The RTU will send the

information given by

the sensors installed

inside the bridge to the

control centre.

eMonitoring System applied to

Tunnel Monitoring SystemMobile

Alert

Devices

for

Urgent

Information

Instrument

inside in

Tunnel

Email &

ftp site

download

Tunnel Monitoring

System featured in

Business Times

13th March 2003

by Infocomm

Development

Authority of

Singapore

Proven Audited

Performance with

System Up-Time of

99.5 %by IDA

Locally

Developed to

suit local

conditions

1.Automatic Measurement and Data capturing

2.Wire-less technologies for data

communications from remote sites

3.Internet web-enable to reach a larger user

base and ease information flow

4.SMS alert to leverage in Mobile phone

networks

5.Lightning and Surge protection

6.Outdoor tropical climate protection design

for sensitive electronics

7.Deploy system which can be supported and

service locally

• Automatic Target

Recognition system

• Glass prism as reflectors

• Range 5 to 1000 m

• Distance Accuracy +/-

1.0mm + 1ppm

• Angular 0.5 arc second

• 60 systems installed in

Singapore

• Highly reliable for

continuous use in Tunnels

Leica High Precision Instrument TCA2003







networks





service locally

Wire-less Data

Communication from

Remote site to user

Reliability of communicationRemote User

12

34

5 6

UserService

Provider

1 2

For the signal to flow through from the Remote site to

the end user, the wired signal has to pass 6

connections. If any connection is down, the

communication is cut off.

Reliability of this system is 1 = 0.015

26

Reliability of the wire-less system is 1 = 0.25

22

An improvement of 16.6 times !

Remote

Wire-less communication is reliable if the setup

is done correctly

The technologies available are :-

• GSM data (Switch Circuit Technology)

• GPRS data (Packet Transmission)

• 2.4 GHz Spread Spectrum

• 802.11g WiFi

• Point to Point radio modem

GSM Signal Strength Level

Challenge of developed New Data Transmission Technique

within 24 hours to overcome signal strength drop out during

Peak periods (~ train move @ 5 minutes intervals !)

GSM RF signal

strength site

survey to ensure

signal level is

reliable for data

transmission.

The Signal

strength is

captured and

logged over 2

weeks to select

suitable antennas

and alignment







networks





service locally


Email &

ftp site

download

Instrument

inside in

Tunnel

Mobile

Alert

Devices

for

Urgent

Information

Most people uses the

Internet for receiving

email information

according to this

survey. The

eMonitoring system

uses the most

popular method to

deliver Tunnel

Deformation

information

email information to end users

Automatic Data

Push method

Data

Download on

Pull method

•Data from site to server using GSM 5 mins

•Processing measured data at server 1 min

•email out to customers within 1 min

•SMS alerts received by users within 1 min

even for cross Telcos

Hence worst case is 8 minutes from site to end

users consistently for every cycle 24 hours a

day. While a manual system with the data is

retrieved manually using wire-less method and

then manually upload to a FTP site

Typical system respond times







networks





service locally

Explosion

of Mobile

users

Wire-less Alarm Notification in demand !

Misinformation & Delay of a Manual

Alert System

Monitoring Worker

Monitoring Sub-Contractor

Main Contractor

Excavation Worker

0.9

0.9 0.9

0.9

Misinformation = 0.94 = 0.65 !

Delay (mins) = 30 + 30 + 30 + 30 = 2 hours

Consultants

Action

Automated Wire-less Alert System

Automated Wire-less

Monitoring System

Monitoring Boss

Main Contractor

Consultants

1.0

1.0

1.0

Misinformation = 1.0 (Manual of 0.65)

Delay (min) = 1.0 (Manual of 120.)

Smart Alert Algorithms

• Differentiate real alerts from glitches

based upon field knowledge rather

than based upon threshold limits

• Need to understand Structural and

Geotechnical behaviors to eliminate

false alerts

• False alerts makes Alert system

unreliable

Uneventful

measurements

Due to Noise

and glitches

SMS Alert

measurement

Event

Alert System

must Guarantee

a 1 min SMS

delivery time to

clients using

different Telcos.

Wrong

technique used

causes SMS

delay for hours







networks





service locally

System Design for

Outdoor

Environment

Use known standards for Lightning

and Environmental Protection

• Lighting Protection CP33

• Environmental Protection IP65

Lightning Protection Code CP33

Misunderstanding of

Code of Practice

Environmental

Protection

IP65

means

Protection

against Dust

and Low

pressure Water

jets

A Proper Protection System is not

just about buying and installing

the correct part numbers

according to catalogue pictures

• Wiring the lightning discharge path

• Isolating the signal, power and

mains earth

• Mains discharge path is different

from signal noise discharge path







networks





service locally

Deploy system which are

supportable and

serviceable

Not just the Best Parts or

Best Brand for the whole

system

Typical challenges in Outdoor

systems

• Ensuring Quality of data

• System works well for first 6 months

• Supporting companies must have

technically manpower to troubleshoot

complex system

• Supporting company must have multi-skilled

staff

• Manufacturer usually do not have local

tropical climatic experiences

The infamous

Dr Frankenstein use

the Best of Everything

to create a Monster who is

made from parts from

different suppliers. A system

has to consider the working

strength and weakness of

all parts

Blue Tooth ?

Pocket PC ?

IEEE802.11g ?

GPRS ?

WAP ?

WiFi ?

3G ?

It is about Deploying Appropriate

Technologies which are stable, reliable

and locally supportable for changes to

suit customer applications

Important from Business View

• What can you add value to your

customers ?

• What you can do for them ?

• Don’t tell the customers what you

technologies you have

• Help customer solve his problem

• Customer don’t buy technology but

solutions

Newton Life Church

Remote Wire-less

Automatic Tunnel

Monitoring System

Requirements

imposed by

Authority

• LTA code of practice allows less than 15mm

movements along the segments

• Tunnel distortion allowable is 1/2000

• Continuously monitors the prisms every 8

hours per day for 7 days a week

• Reliable System up time with penalty

imposed for loss of data

• Real time measurement and immediate data

transmission of results

• Immediate alerts if the movement exceeds

70% of allowable movement

Newton Life Church Extension at Keng Lee Road

Existing

Church

SiteMRT

Line

Initial FE Mesh

Prediction using Finite Element Modeling: Wall Type A

Total Instrumentation Plan: Around the Excavation site

SM16

SM17

SM18 SM19 SM20TM2 CM2

PZ5I5 WS5

SM21 SM22 SM23

CM1

TM1

SM24

SM25PZ6I6

WS6 SM26

SM1

WS1I1PZ1

SM2

SM3WS2I2*PZ2

SM4

SM5

SM6SM7SM8

*PZ3I3

WS3SM9SM10

SM29SM28WS7

SM11

VS3CM3TM3

SM27

WS4PZ4SM12

SM13 I4SM14SM15

Inclinometer

LEGEND :

Water Standpipe

Pneumatic Piezometer

Settlement Marker

Tiltmeter

Crackmeter

Automatic Trainway Monitoring System

Vibration Sensor

Manual Survey


System Operation to achieve

requirements

• Initial setup

• Data Retrieval

• Manual System as a backup support

• Data Comparison

Instrument setup

inside the MRT tunnel

• Manual readings are carried out to record

initial readings for glass prisms

• Once base readings are obtained & set, the

automatic system is commissioned

• Instrument is pre-programmed to take prism

readings

• The captured data is automatically transmitted

from site to office via wire-less means

• Leica APSWin performs the analysis and data

stored

Initial setup

Data Retrieval

• Data retrieved is automatically done 3 times

per day at every 8 hours cycle

• Received prism x,y,z data are automatically

analyzed into tunnel deformation information

• Information is automatically email to the LTA,

clients and consultants

• Results are automatically backup in server

as well as upload to a FTP site

• The results are produced as numerical and

graphical plots

Data Retrieval Consistency

Actual Data

Retrieval

timings

showing the

time and file

size received at

the server end

Typical Numerical Data

Typical Graphical Data

Manual system as a backup

support

• During operation of the Automatic Tunnel

Monitoring system, manual survey is still

being carried out but less often for system

verification purposes

• Readings are captured by another TCA2003

unit for comparison purposes

• Served as a backup and independent audit

from the auto system

Comparison between Automatic

and Manual Readings for one cycle

-10

-8

-6

-4

-2

0

2

4

6

8

10

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Auto

Manual

Lateral Movement for Track Prisms

X (+ ve = movement towards development site)

X

Deviation

in mm

Ring segment number

SysEng (S) Pte Ltd


Pte Ltd

Siber Hagner South East

Asia Pte Ltd

GeoEng Consultants

Thank you for your

Attention from