MBFC Tunnel Monitoring

Transcription

1 MBFC Tunnel Monitoring The Marina Bay Financial Centre (MBFC) is a purpose-built financial district of the new downtown. The construction of the Marina Bay Financial Centre development comprises two phases, with the first phase completed in 3Q The entire development is due for completion in The first phase consists of the office Towers 1 (33 storeys) and 2 (50 storeys), Marina Bay Residences with 428 units and 93,800 square feet of the retail mall. The second phase comprises office Tower 3 (46 storeys), 82,200 square feet of the retail mall and Marina Bay Suites (which will complete in 2013). Monitoring Solution Providers Pte Ltd (MSP) is actively involved in the monitoring of the existing North South line MRT tunnel and Common Service Tunnel (CST) for various clients (e.g. BFC Development Pte Ltd, Econ Geotech Pte Ltd and Tritech Engineering and Testing Pte Ltd) at about 10 sub-contracts for the development at the Marina Bay Financial Centre. The monitoring zones for the sub-contracts overlap each other with many total stations and glass prisms deployed near to each other in intertwining networks. A brief description of the monitoring work carried out by MSP at MBFC with accompanying sketches and layout plans are given below. Protecting Your Future with Monitoring Solution 1 of 20 Tunnel Monitoring

2 (1) PROPOSED COMMERCIAL CIAL DEVELOPMENT AT MARINA BOULEVARD / CENTRAL BOULEVARD (BUSINESS AND FINANCIAL CENTRE) AUTOMATIC TUNNEL MONITORING SYSTEM SUB-CONTRACT AUTOMATED TUNNEL MONITORING SYSTEM IN MRT TUNNEL BETWEEN MARINA BAY AND RAFFLES PLACE MRT STATION (For BFC Development Pte Ltd) An Automated Deformation Monitoring System (ADMS) was deployed at the existing North South line MRT tunnel between Marina Bay & Raffles Place MRT station (from NB CH to NB CH in North Bound and SB CH to SB CH in South Bound) for tunnel displacement and vibration monitoring during the construction activity of the project. This ADMS was officially commissioned on 8 August The instruments used for the system are: 6 Nos. of Sokkia NET1-m-II total stations; 11 Nos. of RST Instantel Minimate Plus TM vibration monitoring sensors The Sokkia NET1-m-II total stations were installed in the MRT tunnel at locations and chainages stated below: Total station Description on Location Chainage STN 1 Inside North Bound Central Wall Crossover Tunnel CH STN 2 Inside North Bound Crossover Tunnel CH STN 3 Inside South Bound Crossover Tunnel CH STN 4 Inside North Bound Cut & Cover Tunnel CH STN 5 Inside North Bound Bored Tunnel CH STN 6 Inside North Bound Bored Tunnel CH The monitoring sensors are located within the North & South Bound MRT tunnel at locations and chainages: Vibration sensor Description on Location Chainage VB 1 Inside North Bound Crossover Tunnel CH VB 2 Inside North Bound Crossover Tunnel CH VB 3 Inside North Bound Crossover Tunnel CH VB 4 Inside North Bound Crossover Tunnel CH VB 5 Inside North Bound Crossover Tunnel CH VB 6 Inside South Bound Crossover Tunnel CH VB 7 Inside South Bound Crossover Tunnel CH VB 8 Inside South Bound Crossover Tunnel CH VB 9 Inside South Bound Crossover Tunnel CH VB 10 Inside South Bound Crossover Tunnel CH VB 11 Inside South Bound Crossover Tunnel CH GMB104 Glass Prism profile will be fixed throughout the influence zone. A typical tunnel cross section will consist of a profile of 4 prisms, except for the Crossover Tunnel where 2 tunnel cross section combines consist of 8 prisms. Protecting Your Future with Monitoring Solution 2 of 20 Tunnel Monitoring

3 STN3 STN2 STN1 to STN3 STN1 Protecting Your Future with Monitoring Solution 3 of 20 Tunnel Monitoring

4 Reference Prism at Marina Bay Station REF (SB) & REF (NB) Protecting Your Future with Monitoring Solution 4 of 20 Tunnel Monitoring

5 Since the monitoring zone involves a cross over section, for the purpose of standardizing the chainage of the prisms in theses location, all prism chainages would be based on the South Bound Tunnel. Fix reference prisms on each side to ensure good redundancy calculation and quality of processed data. The number of reference prism will depend on the site condition. For this particular site, fix reference prisms will be located at both ends of the tunnel (Raffles Place and Marina Bay MRT Station) as there is a monitoring site adjacent to the proposed site currently. As such, it is not adequate to provide fix reference prisms just outside the monitoring zone. The system for each end of the tunnel requires nine (9) fix reference prisms arranged in three (3) prisms per profile. Protecting Your Future with Monitoring Solution 5 of 20 Tunnel Monitoring

6 The 360 change point reference prisms are specially made to reflect EDM emitted from the SOKKIA NET 1m-II from any direction. These prisms are introduced in the system as connection prisms to form a link between 2 or more Total Station. Typical Layout of Prism Side Elevation View Note: Importance of providing good survey geometry between two connecting Automated Total Station, the prisms are spread over 20-30m providing various length and various height and adequate redundancy A generalized layout diagram for ATMS is shown below. Cross-sectional sectional STN STN STN STN STN STN Sending Modem Comms Receiving Modem 24V Uninterrupted Power Supply with minimum 4 hours backup Protecting Your Future with Monitoring Solution 6 of 20 Tunnel Monitoring

7 (2) PROPOSED COMMERCIAL DEVELOPMENT AT MARINA BOULEVARD / CENTRAL BOULEVARD (MARINA BAY FINANCIAL CENTRE) PHASE II AUTOMATIC TUNNEL MONITORING SYSTEM SUB-CONTRACT AUTOMATED TUNNEL MONITORING SYSTEM IN MRT TUNNEL BETWEEN MARINA BAY AND RAFFLES PLACE MRT STATION INITIAL REPORT (For BFC Development Pte Ltd) An Automated Deformation Monitoring System (ADMS) was deployed at the existing North- South line MRT tunnel between Marina Bay & Raffles Place MRT station (from NB CH to NB CH 59376, NB CH to NB CH in North Bound and SB CH to SB CH 59378, SB CH to SB CH in South Bound) for tunnel displacement and vibration monitoring during the construction activity of the project. The ADMS was officially commissioned on 8 August The instruments used for the system are: 2 Nos. of Sokkia NET1m-II total stations 3 Nos. of RST Instantel Minimate Plus TM vibration monitoring sensors Protecting Your Future with Monitoring Solution 7 of 20 Tunnel Monitoring

8 (3) PROPOSED COMMERCIAL DEVELOPMENT AT MARINA BOULEVARD / CENTRAL BOULEVARD (BUSINESS AND FINANCIAL CENTRE) PHASE 2 AUTOMATIC TUNNEL MONITORING SYSTEM SUB-CONTRACT AUTOMATED TUNNEL MONITORING SYSTEM IN MRT TUNNEL BETWEEN MARINA BAY AND RAFFLES PLACE MRT STATION (For BFC Development Pte Ltd) Phase 2 R2 An Automated Deformation Monitoring System (ADMS) was deployed at the existing North- South line MRT tunnel between Marina Bay & Raffles Place MRT Station (from NB CH to NB CH in the North Bound and SB CH to SB CH in the South Bound) for tunnel displacement and vibration monitoring during the construction activity of the Marina Business Financial Centre Phase 2 R2 development. The Initial Readings were obtained on 26 th December 2007 and the instruments used for the system are: 2 Nos. of Sokkia NET1m-II total stations installed in the MRT tunnel at location and chainage as stated below. Total station Description on Location Chainage STN 3 Inside South Bound Crossover Tunnel CH STN 4 Inside North Bound Box Tunnel CH STN 8 Inside South Bound Box Tunnel CH Protecting Your Future with Monitoring Solution STN3 to STN4 & STN8 8 of 20 Tunnel Monitoring

9 (4) PROPOSED COMMERCIAL DEVELOPMENT AT MARINA BOULEVARD / CENTRAL BOULEVARD (BUSINESS AND FINANCIAL CENTRE) PHASE 2 AUTOMATIC TUNNEL MONITORING SYSTEM SUB-CONTRACT AUTOMATED TUNNEL MONITORING SYSTEM IN MRT TUNNEL BETWEEN MARINA BAY AND RAFFLES PLACE MRT STATION (For BFC Development Pte Ltd) Phase 2 - T3 An Automated Deformation Monitoring System (ADMS) was deployed at the existing North- South line MRT tunnel between Marina Bay & Raffles Place MRT Station (from NB CH to NB CH in North Bound and SB CH to SB CH in South Bound for tunnel displacement and vibration monitoring during the construction activity of the Marina Business Financial Centre Phase 2 T3 development. The Initial Readings were obtained on 26 th December 2007 and the instruments used for the system are: 3 Nos. of Sokkia NET1m-II total stations installed in the MRT tunnel at location and chainage as stated below. Total station Description on Location Chainage STN 1 Inside North Bound Central Wall Crossover Tunnel CH STN 2 Inside North Bound Crossover Tunnel CH STN 7 Inside South Bound Crossover Tunnel CH Protecting Your Future with Monitoring Solution 9 of 20 Tunnel Monitoring

10 STN1 & STN7 Protecting Your Future with Monitoring Solution 10 of 20 Tunnel Monitoring

11 Monitoring Solution Providers Pte Ltd (MSP) is also involved in the monitoring of existing North South line MRT tunnel for the construction of the Downtown Line in the Marina Bay area. Two of the Land Transport Authority s Downtown Line construction projects which MSP participated in are C901 and C907. PROPOSED DOWNTOWN LINE C901 AUTOMATIC TUNNEL MONITORING SYSTEM FOR NORTH SOUTH LINE MRT TUNNEL FROM MARINA BAY STATION TO OVER RUN AREA Contract 901 is for the construction and completion of the Marina Bay station and tunnels. The scope of the contract also includes addition and alteration works to the existing North South Line (NSL) at Marina Bay station, diversions as well as demolition of an underpass. An Automated Deformation Monitoring System (ADMS) was deployed at the existing North South Line MRT station and tunnel from Marina Bay Station to the overrun area for structural deformation and displacement monitoring during the construction activity of the project. The ADMS was officially commissioned on 8 July 2008 and the instruments used for the system are: 3 Nos. of Sokkia NET1m-II in North Bound Tunnel 3 Nos. of Sokkia NET1-m-II in South Bound Tunnel The manual monitoring of the Marina Bay MRT Station, North & South tunnel monitoring towards Over Run was covered from NB CH to NB CH with a total length of 325m and from SB CH to SB CH with a total length of 320m. The monitoring system consists of 4 points inside the Bored Tunnel for each ring (i.e. Top, Bottom, Crown & Track Bed). 4 points were also installed for the Station Box (i.e Right, Track Bed, Right Bottom & Right Top). Protecting Your Future with Monitoring Solution 11 of 20 Tunnel Monitoring

12 DOWNTOWN LINE: CONTRACT 907 The Land Transport Authority (LTA) has awarded the civil works contract (C907) for Downtown Line Stage 1 Landmark Station to Taisei Corporation, valued at S$230.3 million. The Landmark Station is located at Central Boulevard near the Marina Bay Financial Centre. The contract covers the construction and completion of the Landmark Station and tunnels. The station will be connected via underground subway links to the Marina Bay Financial Centre. The contract also includes the construction and completion for the main trunk road, Central Boulevard, above the station. An Automated Deformation Monitoring System (ADMS) was deployed at the existing North South Line MRT station and tunnel from Marina Bay Station to Raffles Place Station for the structural deformation and displacement monitoring during the construction of the project. The instruments used for the system are: 3 Nos. of Zeiss ELTA S10 in the tunnel as stated below. Total station Description on Location Chainage STN N1 Inside North Bound Box Tunnel CH STN N2 Inside North Bound Box Tunnel CH STN N3 Inside North Bound Box Tunnel CH Nos. of Sokkia NET 1m-II total stations with bracket installed in the MRT tunnel at location stated below: Total station Description on Location Chainage STN 9 Under Existing MBFC STN 1 CH STN 10 Under Existing MBFC STN 2 CH STN 11 Under Existing MBFC STN 3 CH Nos. vibration monitoring sensors located within the North & South Bound Tunnel at location stated below: Vibration sensor Description on Location Chainage VM 1 Inside North Bound Crossover Tunnel CH VM 2 Inside South Bound Crossover Tunnel CH MB104 monitoring glass prisms were fixed throughout the influence zone. A typical tunnel cross-section will consist of a profile of 4 prisms, while at the Crossover Tunnel, 2 tunnel cross-sections combine to 8 prisms. Fix reference prisms located at both ends of the tunnel (Raffles Place and Marina Bay MRT Station ensure good redundancy calculation and quality of processed data. The number of reference prism will depend on the site condition. As there is a monitoring site adjacent to the proposed site, it is not adequate to provide fix reference prisms just outside the monitoring zone. The system for each end of the tunnel requires 9 fix reference prisms arranged in 3 prisms per profile. 360 change point reference prisms are specially made to reflect EDM emitted from the Sokkia NET1m-II from any direction. These prisms are introduced in the system as connection prisms to form a link between 2 or more total stations. Protecting Your Future with Monitoring Solution 12 of 20 Tunnel Monitoring

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14 AUTOMATED TUNNEL MONITORING SYSTEM FOR COMMON SERVICE TUNNEL MBFC PARCEL (T3 & R2) - 3 nos. Sokkia NET1-m Total Stations on wall mounted bracket will be installed in the CST tunnels. STN A Under MBFC Parcel T3 STN B Under MBFC Parcel R2 STN C Under MBFC Parcel R2 - GMB104 glass prism will be fixed throughout the influence zone. A typical tunnel cross section will consist of a profile of 4 prisms; refer to the cross-section diagram of the tunnel below. Typical Sectional Layout Fix reference prisms are needed to ensure good redundancy calculation and quality of processed data. The number of reference prisms will depend on the site condition. For this particular site, fix reference prisms will be located at both ends of the tunnel outside each monitoring zone. There will be at least 6 reference prisms at each of the monitoring zone. A generalized layout t diagram for ADMS in one tunnel bound is shown below. Protecting Your Future with Monitoring Solution 14 of 20 Tunnel Monitoring

15 DOWNTOWN LINE: CONTRACT 907 CST An Automated Deformation Monitoring System (ADMS) was deployed at the existing Common Service Tunnel at Parcel R2 and Parcel T3 for the structural deformation and displacement monitoring during the construction of the project. The instruments used for the system are: 2 Nos. of Sokkia NET1-m in Parcel R2 1 No. of Sokkia NET1-m in Parcel T3 Protecting Your Future with Monitoring Solution 15 of 20 Tunnel Monitoring

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18 PROJECT PHOTOGRAPHS Protecting Your Future with Monitoring Solution 18 of 20 Tunnel Monitoring

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20 33 Ubi Avenue 3, #05-31, VERTEX Singapore Tel: Fax: Website: Co. Reg No: W Protecting Your Future with Monitoring Solution 20 of 20 Tunnel Monitoring