VSL Activities

VSL Multistrand
VSL Bonded Slab
Bridge construction
Stay Cables
Heavy Lifting
Ground Engineering
Ground Anchors
VsoL® Retained Earth
Infrastructure Protection
VSL Offshore
Forming System
VSL Bearing System
Structural Monitoring


VSL MULTISTRAND

INTERNAL MULTISTRAND POST TENSIONING
SYSTEM DESCRIPTION

Technical data and dimensions are given in the annexes. For reasons of clarity and simplicity, anchorage reinforcement are not shown in the pictures. Primary bursting and secondary equilibrium reinforcement form an integral part of the anchorage and are required to control local zone stresses. For more detailed information on the anchorage zone design, see VSL’s Report Series on “Detailing for post-tensioning”.

MAIN CHARACTERISTICS

The VSL multistrand system is characterized by the following features:
+ Standardized tendon units using up to fifty-five 13mm (0.5”) or 15mm (0.6”) diameter strands;

+ Wide selection of anchorage types;

+ Steel or plastic PT-PLUS® ducts;

+ VSL HPIR grout or other types of grouting;

+ Tendons manufactured on-site or in the factory;

+ Not required to determine tendon length in advance;

+ Simultaneous stressing of all strands in a tendon,with individual locking of each strand at the anchorage point;
+ Stressing carried out in any number of phases;

+ Simple and reliable equipment for installation, stressing and grouting.


FOR MORE INFORMATION, PLEASE REFER TO THE VSL STRAND SYSTEM BROCHURE
Bridge Over Sg. Serangoon
Singapore LNG Tank
Marina Bay Sands
Multistrand Anchor Block
EXTERNAL MULTISTRAND POST TENSIONING
BKE Widening
RD122-Vehicular Upgrading


Stressing of Upgrading External PT
SYSTEM DESCRIPTION

External post-tensioning is well adapted to bridges due to the resulting reduction of congestion inside the concrete and the high degree of corrosion resistance provided by the system. External tendons are easy to inspect and, if necessary, replace. They are ideal for strengthening existing structures and, apart from their uses in bridges, can be used for a wide range of other applications, including buildings, silos and reservoirs

VSL external tendons comprise:
+ Strand bundle;
+ Polyethylene ducts;
+ Standard multistrand anchorages, and special anchorages permitting complete tendon replacement;
+ Grouting compound.
TRAJECTORY OF EXTERNAL TENDON

In order to allow replacement, the trajectory of an external tendon requires to be a polyline, consisting of only straight and curved sections with constant radii of curvature.

The construction of the trajectory is easiest preformed by:

+ definition of the fix points (FP) and straight section at the anchorage

+ definition of work points (WP, intersection of tangents of straight lines) at high points and at deviators

+ construction of straight lines between working points

+ define curved section between straight lines with required constant radii of curvature

MULTISTRAND POST TENSIONING
Stressing Anchorages & Intermediate Anchorages

All VSL stressing anchorages can be used as a dead-end anchorage if access is provided. For dimensions of anchorages see annexes. Anchorage components are not available in all countries. Please check with your local VSL office for availability.



TYPE GC 0.6’
This is a compact and easy to handle anchorage system. If necessary, the spiral can be replaced by suitably laid out orthogonal reinforcements.







COUPLERS VSL TYPE K
This fixed coupler is used for connections to a cable that has already been installed and stressed. The strands are anchored using compression fittings positioned onto the coupling head grooves.








TYPE SC 0.5’
This is a compact and easy to handle anchorage system. If necessary, the spiral can be replaced by suitably laid out orthogonal reinforcements.






INTERMEDIATE ANCHORAGE TYPE Z
Intermediate anchorages are used for those tendons where the ends cannot be fitted using normal stressing anchorages.

The anchorage head is loosely placed in the blockout and moves during the stressing operation on the tendon axis. Z type intermediate anchorages are used:

+ For pressure shaft and pressure tunnel ring tendons, avoiding the use of internal buttresses;

+ For silo and reservoir circular structure ring tendons, avoiding the use of external buttresses;

+ For frame, arch, foundation rafts and shell structure tension ties where there is no limited access to end anchorages.

MULTISTRAND POST TENSIONING
Dead-End Anchorages



VSL TYPE H
This type of anchorage is the best solution when strands need to be pushed through on site.

The prestressing force is transferred to the concrete partially by bond and partially by end bearing (bulb). The spiral (for 5-7 / 6-7 and larger units) and tension ring prevent inadmissible stresses due to deviation forces acting on the concrete. The rebar net at the anchorage end zone acts as a spacer for individual strands.



VSL TYPE AF
This type of anchorage is used for vertical tendons installed once a structure is concreted, where the prestressing force has to be transferred to the structure at the lowest end of the tendon and when there is no access to the dead-end anchorage. The strands are placed in the tendons with compression fittings at their lower ends, which are then bonded into the AF anchorage with a special cement AF grout. Once the AF rout anchorage has achieved sufficient strength the tendon can be stressed from the anchorage and then grout.




VSL TYPE P
This type of anchorage is used where the prestressing force has to be transferred to the structure at the far end of the tendon. It consists of a plate incorporating holes for the strands to pass through.The strands are anchored using compression fittings bearing onto the plate. The compression fittings are locked into position by a retainer plate. Where the force shall only be transferred to the concrete using a bearing plate, polyethylene tubes can be used to sheath the strands between the end of the duct and the bearing plate.







VSL TYPE L
This type of anchorage is used for tendons installed once a structure is concreted and where there is no access to the dead-end anchorage. It is often used for vertical tendons in reservoir walls, for nailing pier head segments to piers in segmental bridge construction, or for horizontal tendons in slabs or foundation rafts.The strands are installed into the duct after concreting and simultaneously stressed using jacks at both stressing anchorage ends.
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VSL BONDED SLAB

The VSL bonded post-tensioning slab system has been used in many prestigious buildings, brigdes and other structures. The system uses up to five strands 13mm (0,5") or 15mm (0,6") contained in flat-shaped ducting, and anchored in a single anchorage.

Strands are individually stressed and gripped by wedge action. After stressing, the duct is filled with a cement grout that fully bonds the strands to the surrounding concrete.

Post-tensioning provides greater spans with reduced structural floor depths, resulting in large column-free areas. As a result, internal layouts are not dictated by tight column grids. Positive deflection and crack control and, if necessary, joint-free water-tight slabs, free designers from the limitations of traditional reinforced concrete structures. VSL post-tensioning is more economical than other systems, especially when fast construction cycles are envisaged. There is less material handling on site and a reduced labour force, minimizing site congestion. Most importantly, there is the quality and service provided by VSL's specialized highly efficient teams.

LAYING OF POST TENSIONING TENDONS

Tendon Laying

Kallang Avenue

Marina Bay Sands

Motor Workshop at Sin Ming
BONDED SLAB POST TENSIONING
Grouting
Grouting Test - Flow Cone Test
Grouting Test - Mud Balance Test
Grouting Test - Pressure Test
Grouting

OBJECTIVES OF GROUTING
The objectives in grouting a tendon are :

1. To provide an effective corrosion protection system, by filling the free space in the tendon with the grout which provides an alkaline encapsulation of the tendon.

2. To archive an effective bond between the tendon and the surrounding concrete. It is therefore essential that grouting be carried out in a carefully monitored and controlled manner.

Quality of the grouting is of prime importance for the durability of post-tensioning tendons for any kind of application.

Quality of grouting is achieved through :

+ Careful selection of the constituent materials
+ Continuous quality control to assure consistent material properties
+ Selection of mix design and mixing procedures adapted to the selected materials, environment and equipment.
+ Effective cable encapsulation.
+ Execution of grouting on site by qualified personnel following approved method statements.

VSL POLICY ON GROUTING
IT is the policy of VSL that all entities comply and carry out grouting in accordance with EURONORM namely the followings :

EN445
Grouting for prestressing tendons - Test Methods

EN446
Grouting for prestressing tendons - Grouting procedures

EN447
Grouting for prestressing tendons
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BRIDGE CONSTRUCTION

System description
LTA Tuas West MRT Extension
Bridge Across Sungai Serangoon
VSL EXPERIENCE
With extensive experience in large infrastructure and superstructure projects, VSL has a proven record of developing project specific construction systems and methods that promote highly efficient rates of construction and facilitate programme schedule, while maintaining and often improving essential safety and quality control measures.

Lateral thought processes encouraged within the design and production teams provide a suitable environment in which to nurture novel, and often remarkably simple solutions to demanding problems.

The exchange of knowledge within the VSL global network enables the group’s considerable experience
Jubilee Bridge

to be fully utilised and applied in a wide variety of engineering domains

As a specialist bridge partner, VSL can bring the project team an extensive experience gained from erecting over 100,000 precast bridge deck elements (providing almost 5 million square meters of bridge surface) and also constructing multiple insitu bridges utilising VSL form travellers and incremental launching methods. VSL is committed to offering clients a ”best for project” service that has recently led to the development and successful implementation of various innovative Partnering and Alliancing arrangements that have proved to be highly successful and mutually beneficial to all parties involved.
BRIDGE CONSTRUCTION
TPE Sengkang Flyove
Sentosa Second Link Bridge
VSL SOLUTIONS
+ Precast segmental erection balanced cantilever construction with launching gantry method

+ Span by span construction with launching gantry

+ Balanced cantilever construction with lifting frames

+ Balanced cantilever construction with cranes

+ Precast beam construction

+ Full span precast construction

+ Span by span erection on falsework

+ Insitu construction by incremental lauching method

+ Form traveller method

FOR MORE INFORMATION, PLEASE REFER TO THE VSL BRIDGE CONSTRUCTION BROCHURE.
LTA Tuas West MRT Extension

Bukit Panjang Flyover

Bartley Flyover
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STAY CABLES

SSI 2000E Stay cable system

VSL STAY CABLE SYSTEM
The VSL stay cable system was developed to meet the stringent design, construction and maintenance requirements of cable-stayed bridges.

The VSL stay cable system comprises
+ a tendon formed from multiple and parallel 15-mm (0.6”) dia. high tensile 7-wire steel strands;

+ a greased or waxed strand, with a tightly extruded plastic sheathing.

+ an outer thick-walled plastic stay pipe;

+ factory prefabricated anchorages

The system features are as follows
+ 200 MPa minimum fatigue resistance at 45% of tendon capacity over 2,000,000 load cycles;

+ high degree of corrosion resistance using multi-layer corrosion protection;

+ an extruded coating providing excellent strand corrosion protection during construction;

+ an extruded coating providing excellent strand corrosion protection during construction;

+ individual strand encapsulation and sealing in anchorages;

+ easy installation of the strands into the erected stay pipe (single strand installation);

+ all strands are parallel with no risk of twisting;

+ single strand stressing;

+ no requirement for on-site cable grouting;

+ easy tendon force monitoring and adjustment throughout the cable’s service life;

+ ability to remove and replace individual strands without dismantling the installed anchorages, or the entire cable at any time;

+ system adapted for the initial or future installation of an antivibration damper.

STAY CABLES
Industrial Ring Road, Thailand
CHARACTERISTICS
Compactness
+ reduced size of the anchorage for easy installation and savings in the cost of the structure.

Aesthetics
+ using coloured co-extruded stay pipes, different colours can be obtained;

+ vibration damping devices can be placed at the end of the guide pipes near the deck.

Dynamic stability of the cables
+ stay pipes with external helical ribs to suppress rain-wind induced vibrations;

+ the stay cable system is adapted for the initial or future installation of anti-vibration dampers.

+ the new generation of VSL friction or Gensui dampers dampers to offer minimum maintenance during extended design life.

Durability
A high degree of corrosion protection:
+ each strand is individually protected not only in the stay pipe, but also in the transition part of the anchorage;

+ individual anchorage sealing joints protect each strand not only in service, but also during bridge erection;

+ VSL’s stay cable system has the unique feature of providing complete encapsulation for each individual monostrand along the free length and into the anchorage.

+ Unlike systems used by competitors which compromise the encapsulation near the anchorage point and result in potential exposure of the entire cable, VSL’s stay cable system reduces the potential exposure to a single strand.

Reduced maintenance costs
+ easy corrosion control of anchorage components;

+ good access to vibration damping systems.

Stay cable installation
+ system optimised for strand-by-strand installation, with easily handled, lightweight equipment and reduced construction loads on the bridge during construction

VSL stays with architectural bars
+ VSL architectural bars are particularly suitable and economical for shorter road bridges, pedestrian bridges and stays for suspended roofs.

Single strand monitoring
+ VSL has designed a compact load cell, the SSI 2000 Hc160, to monitor the load on a single strand within a stay cable.This new equipment fits over one strand and sits on the anchor head of the stay cable between adjacent strands, making it easy to install and replace.This load cell offers an economical way to have a good indication of the total force on the stay cable


FOR MORE INFORMATION, PLEASE REFER TO THE VSL BRIDGE CONSTRUCTION BROCHURE.
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HEAVY LIFTING

Marina Bay Sands Sky Park
Singapore Sportshub Roof Lowering


CUSTOM ENGINEERED SOLUTIONS FOR TOUGH JOBS
For economic or technical reasons, today’s civil engineering structures and industrial plants are often assembled from large, heavy, prefabricated components. VSL Heavy Lifting will often provide the most effective solution for projects where cranes or other conventional handling equipment cannot be used.

Individual solutions
VSL can plan lifting, horizontal jacking, or lowering operations and design the necessary temporary structures needed to meet your requirements.

Safety
The safety of your personnel and works is VSL’ s first priority. Our specialized hydraulic lifting equipment is designed to provide the highest level of reliability, and VSL field services are based on a total commitment to safety devices and modular lifting /jacking.

Flexibility
Our equipment includes a large number of hydraulic strand units, jacks, pumps, control units, monitoring frames, giving us the capacity to perform virtually any project requiring lifting, lowering or horizontal jacking.
Changi Airport Terminal 3
Spine Bean
VSL service package
Our approach is flexible, and the range of our services is tailored to the specific project requirements. They include:

+ feasibility studies and preliminary consultation;

+ project design and planning;

+ design, manufacture, and supply of special equipment;

+ leasing of VSL equipment and execution of work.


PROVEN EQUIPMENT FOR HANDLING HEAVY LOADS
VSL strand system
The main components of the VSL strand system are the motive unit, the tensile member with the anchorage for the load, and the pump with its controls.

Motive unit
The motive unit consists of a hydraulic centre hole jack with upper and lower anchorages. During lifting the jack is extended, causing the individual strands of the tensile member to be gripped by the upper anchorage and thus to be moved upwards. At the start of the pistons downward movement, the strands are
HEAVY LIFTING
Singapore Flyer
immediately gripped by the lower anchorage. In this way, the load is raised using a step-by-step process.

For lowering operations, VSL’ s motive units are equipped with an auxiliary device which automatically controls the opening and closing of the anchorages. Tensile member
The tensile member consist of 15 mm (0.6”) strands. The tensile member is anchored to the load by a specially designed end anchorage.

Hydraulic pumps
VSL electro-hydraulic pumps can be manually controlled or operated in groups from a central control board.

VSL has a wide range of pumps with either single or multiple outlets.The characteristics of these pumps ensure the synchronised movement of the jacks. Pressure control devices allow forces to be monitored at all times. The movement speed varies according to the project and, if required, can be in excess of 20 m / hour.
SLU Jack Capacity Range from 10 Ton to 580 Ton
Control and monitoring systems
The lifting of hangar roofs or of similar statically overdetermined structures usually requires that lifting movements be precisely co-ordinated.

This is achieved by specially designed, computer-based multi-point monitoring systems, which allow the operation to be centrally controlled and monitored up to the final, precise height.

Special hydraulic equipment
Our range of equipment also includes a large number of different hydraulic jacks. VSL can also design and supply custom-built hydraulic systems for special applications.





FOR MORE INFORMATION, PLEASE REFER TO THE VSL HEAVY LIFTING BROCHURE.
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GROUND ENGINEERING

EXPERIENCE BUILT THROUGHOUT A LONG HISTORY Intrafor is the specialist ground engineering and foundations subsidiary of the VSL Group.

Originally founded in 1850 in France, Intrafor has developed into a well-established and recognized foundation partner for developers, consultants and contractors worldwide.

FOUNDATIONS AS THE CORE BUSINESS
VSL-Intrafor provides a wide and comprehensive range of professional services starting with feasibility studies and design development, through to construction completion. VSL-Intrafor is able to carry out all the ground engineering techniques needed for retaining structures, soil improvement and environmental protection. Its works form the foundations of civil engineering or building projects such as metro stations, tunnels, roads and bridges, land reclamation, deep basement, car parks and high rise buildings.

SOLUTION FINDERS
Its own internal design capabilities enable VSL-Intrafor to target the full project scope from the earliest stages of design and the selection of the optimum solution through to turnkey solutions tailored to customer needs.

+ Diaphragm Wall

+ Piling

+ Jet Grouting

+ Soil Freezing

+ Stone Columns

+ Soil Investigation

+ Ground Anchors

+ Vibro-Compaction

+ Directional Drilling

+ Directional Coring

Mechanical clamshell
Trench cutter, up to 120m capacity
Hydraulic drill rig


GROUND ENGINEERING
Marine stone columns, Qatar, New Doha Port
Diaphragm wall, Downtown Line C909Chinatown Station, Singapore
Deep foundations, AsiaWorld Expo, Hong Kong
Extensive experience and expertise in a broad range of soil engineering techniques mean that VSL-Intrafor offers not only the best technical solutions but also innovative construction techniques designed to improve safety, save time, improve durability and reduce costs.

VSL-Intrafor is always committed to working in partnership with its clients right from the conceptual stage.

EXPERIENCED STAFF
VSL-Intrafor's project teams are organized around a permanent core of highly experienced and mobile staff, guaranteeing the highest quality of work, safety standards and problem solving.

RAPID RESPONSE & MOBILIZATION
VSL-Intrafor has the capabilities and experience to mobilize 'commando teams' at very short notice all over the world thanks to the support of the VSL local network.

VSL Intrafor's multi-culturalism and open-minded approach ensure that project teams adapt seamlessly to any project anywhere.



OUR OWN SPECIALIST EQUIPMENT POOL
VSL-Intrafor owns its pool of specialized equipment and continuously renews and expands it to ensure that the best equipment is available to projects

FOR MORE INFORMATION, PLEASE REFER TO THE VSL GROUND ENGINEERING BROCHURE.

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GROUND ANCHORS

VSL Anchors can be divided into two main categories — strand and bar anchors.The type of anchors used depends on whether it is for rock or soil, for temporary or permanent use, whether or not it is to be tensioned, and whether or not permanent corrosion protection is required.

SUSTAINABILITY
Saving of material
Ground anchors are an efficient way of mobilizing dead loads deep in the ground to resist forces induced by wind, suspension cables (bridges, cable cars, cable trains, etc.) and other tension forces that would otherwise require large gravity foundations.

Durability
VSL Ground Anchors comply with the most stringent international specifications with regards to corrosion protection.

Removability
VSL Ground Anchors can be made extractable in order mitigate the impact on adjacent ground when no longer required.

PERMANENT VSL STRESSBAR ANCHOR FULLY ENCAPSULATED


Completed Temporary Ground Anchor
Fabrication of U-Turn Anchorages
Stressing of Temporary Ground Ancho


FOR MORE INFORMATION, PLEASE REFER TO THE VSL GROUND ANCHOR BROCHURE.
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VSoL® RETAINED EARTH

Nundah Bypass, Australia
Upper Bukit Timah Road, Singapore
Penny’s Bay, Hong Kong
VSoL® wall with Vstrip Reinforcement
VSoL® wall with Steel Mesh Reinforcement
The VSoL® retained earth system is a composite soil reinforcing system that uses welded wire mesh or polymeric strips to resist the horizontal forces generated within an earth backfill. A retained each structure is a stable, unified gravity mass that can be designed for use in a wide range of civil engineering applications. The VsoL® system is widely used and accepted as a major construcion method in projects ranging from retaining walls to highway bridge abutments. The basic retained earth principle involves transferring stresses from the soil to the reinforcing elements. In the case of welded wire mesh soil reinforcements, this is achieved by the development of passive resistance on the projected area of the mesh crossbars, which in turn transfers load into the longitudinalbars. In the case of polymeric strip reinforcement, load transfer from the backfill is achieved by the frictional interaction of the soil particles with the polymeric reinforcing strip. In addition to its high performance level, the VSoL® system ensures economical design and construction. The system requires only three components: reinforcing elements, precast facing panels and backfill material. This simplicity results in easy and rapid construction. Cost savings of up to 50% below those of traditional retaining wall systems are regularly achieved.

FAST, EASY AND ECONOMICAL
The construction of a VSoL® structure id particularly straightforward.

A five-man crew using strandard construction equipment can place an average of 75 m² - and as much as 140m² - of wall per shift.

FOR MORE INFORMATION, PLEASE REFER TO THE VSoL® BROCHURE.
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INFRASTRUCTURE PROTECTION

INTRODUCTION
VSL Infrastructure Protection designs and constructs resilient solutions for critical infrastructure at risk of extreme events; including blast, projectile, impact, seismic and fire effects. With specialist knowledge in global construction, and access to leading-edge research and technology, VSL Infrastructure Protection safely delivers quality, innovative construction solutions with reduced risk. We pride ourselves on our ability to build relationships with clients and suppliers across the globe.

Our commitment to excellent communications alongside the fact that we never underestimate the importance of local knowledge ensures that our projects are successful, sustainable and cost effective.

OUR SERVICES
Our proposition spans a range of engineering services, to be able to deliver a turnkey asset protection service.

Partnering with a specialist engineering consultancy, we offer the following services:

+ Vulnerability Assessments: to determine the consequence for a structure due to an extreme event including blast, accidental explosions, projectiles, vehicle impact, earthquakes and fire.

+ Mitigation Analysis & Design: conceptual design through to fabrication detailing and construction methodologies.

+ Construction Delivery: across all stages of project implementation, including procurement, supply, on-site project management, commissioning and maintenance.

Our expertise in construction management, delivery and on-site installation allows our clients to give us the brief, approve the design and have a turnkey solution delivered to them complete with commissioning of the project.

This reduces the risk of the constructed solution not meeting the design intent, minimising the time and effort required for our clients.

OUR SOLUTIONS
We work on new construction projects as well as retro- fitting existing structures that need enhanced protection. Our solutions include:

+ Physical Perimenter Security including security fencing, boundary walls, boundary wall enhancements (VSL Anti-Spall Liner) and vehicle barrier systems (shallow mount fixed post and retractable bollards, gates, vehicle barrier arms).


Algiers, Algeria
London United Kingdom
Reinforced concrete perimeter wall with VSL Blast Resilence Upgrade System
+ Asset Shielding including overhead protection and shielding walls.

+ Structural Systems Resilience including progressive collapse prevention and cable protaction.

+ Built Infrastructure Enhancements including intruder, ballistic and blast resistance for walls, doors and windows, as well as entire building areas and rooms.

+ Specialist Resilient Structures that may include guardhouses, temporary accommodation, control, safe and mail rooms.

FOR MORE INFORMATION, PLEASE REFER TO THE VSL INFRASTRUCTURE PROTECTION BROCHURE.

WEBSITE: WWW.VSL-IP.COM
EMAIL: INFO@VSL-IP.COM


PROTECTION SYSTEM

MICROSOFT DATA CENTRE, WOODLANDS SINGAPORE
VSL IP completed the perimeter physical security works for the new nine-storey building, where it designed, supplied and installed the crash rated gates and barriers, bollards, turnstile and over 550m of anti-ram security fencing within the compressed program to the high standards and stringent security requirements.
SINGAPORE SPORTS HUB, SINGAPORE
VSL IP engaged for the supply, installation and maintenance of fixed and retractable bollards, wedge barriers and blast doors of the iconic sports and leisure venue, which offers world-class facilities for sports, events, concerts, exhibitions and international trade shows.




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VSL OFFSHORE

VSL Offshore Interest
Caissons Tangier Med II, Morocco

A dedicated entity targeting onshore and offshore opportunities relating to:

+ Oil/ gas/petrochemical sectors (FSO/FPSO/ FLNG/GBS/LNG)

+ Renewable/sustainable energy sectors (offshore wind farm, floating bioenergy solutions)

+ Offshore civil works structures (e.g. breakwaters)

+ A LNG competence centre:
     - Upstream business development and tender support to local profit centres for full scope LNG tank works
+ Consolidation of LNG “know-how”, experience

+ Development of relationships with major EPC contractors

Engaging into strategic partnerships with major players in the field
NKOSSA barge

VSL OFFSHORE INTEREST
VSL Offshore offers:
+ Innovative construction methods
+ Temporary works design
+ Tender assistance
+ Project execution.

Applications:
+ Floating structures
+ Gravity base structures
+ Wind farm foundations
+ Containment structures
OFFSHORE SERVICES
SLNG tanks at Jurong Island
SLNG tank Roof structure
SLNG tank construction works

Typical Project Delivery Mechanism

PRE CONTRACT AWARD
Concept, Feasibility & Feed Stages
+ Preliminary structure design
+ Feasibility studies
+ Constructability studies
+ Project schedule analysis
+ Cost analysis Tender preparation

POST CONTRACT AWARD
Detailed Design & Build Stages
+ Structure optimisation / rationalisation
+ Technical coordination with designers / clients
+ Detailed project scheduling
+ Construction engineering and methods
+ Temporary works design
+ Plant, equipment & material procurement
+ Logistical planning
+ Mobilisation of experienced VSL project team
+ Project management
+ Site establishment
+ Project execution:
   - Foundations
   - Civil works
   - Monitoring
   - Structural preservation/ Protection

FOR MORE INFORMATION, PLEASE REFER TO THE VSL OFFSHORE BROCHURE.
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FORMING SYSTEM

VSL CLIMBFORM
VSL has also been active in Climbforming for over 20 years. The VSL Climbform System is a self climbing heavy duty construction platform used primarily to lift static panel vertical wall formwork. The system provides the wall designer with complete flexibility in both the structural design and selection of finishes. The system is particularly adapted to the construction of high-rise building cores. The 6m high VSL Climbform has three platform levels, and the formwork panels hanging from the eternal frame and internal platforms permit pours over a height of 4.2m. The internal steel platforms, incorporating the formpanel hooks and rollers, are specifically designed and manufactured for each project, guaranteeing accurate and economic assembly operations.

VSL Climbform permits an excellent production ratio with accurate placing of door frames, openings, blockouts, cast-in components and direct placing of prefabricated reinforcement cages. Another advantage lies in the safety of the Climbform. The VSL service package includes: feasibility studies and preliminary consultation and pricing; tender design and planning; design, manufacture and supply of equipment; leasingm training of site staff, supervision of the works for the first few levels, followed by dismantling operation.

Standard features include:
+ Custom designed formwork panels which may be ganged in any shape or size to lift as one unit

+ form heights ranging from 2.5 to 4.2 metres
+ unobstructed access to the forms for cleaning and oiling, fixing of door frames and blockouts as well as reinforcement and reinforcing fabric fixing, including prefabricated reinforcement

+ tress members of fixed height assembled in “Meccano like fashion” to form a platform of any plan shape or size

+ easy levelling and plumbing of the external platform, which is typically supported on four, six or eight seatings

+ minimum adjustment of individual forms after the inital set-up

+ an achievable vertical tolerance range of 10mm per 4.2 metre height

+ variation of wall thickness by moving the internal or external forms

+ parking the internal platforms at mid-lift to facilitate blockoutand reinforcement fixing, eliminating the requirement for temporary scaffolds

+ cycle times as low as three days

+ access to external walls for curing

+ hanging access stairway.

Central Plaza
Gateway II
VSL Climform Sys


Optional features include:

+ steel formwork to enable pouring within 50mm of boundaries

+ support of concrete placing booms on the platform

+ access hatches and/or temporary removal of platforms to install precast stairs

+ external trailing platforms

+ internal trailing platforms to allow early installation

+ support of site sheds and toilets on the platform

+ provision to allow manhoists to service the top working platform

+ provision to locate tower cranes within internal and corridor platforms

+ collapsible door formers

+ trailing formwork and platforms for vertical and raking walls.




DI Wang,Shenzhen, China


FORMING SYSTEM

Deep bay Link, Hong Kong
Light Rail Transit, Dubai
Bridge across Sungei Serangoon. Singapore
VSL has considerable experience in a wide variety of in situ form system ranging from self climbing form systems utilised for pier and pylon construction to large span underslung movable scaffold support systems. To complement any precast erection operation, VSL is also able to provide detailed design, supply and operation of precast cells required for precast segmental bridge decks, precast beams, and also full span precast elements. Recently, on the Taiwan High Speed Rail Project, VSL was responsible for the complete establishment and operation of the casting yard including reinforcement and concreting operations. VSL form systems are generally modular, lightweight and provide clear unobstructed access to all necessary working areas. Mechanised VSL Form Systems facilitate casting of highly complex structures with variable geometric properties, and produce high quality finishes often required by clients.

VSL managed casting yards regularly achieve precast segmental production rates of up to one segment per day, per cell.

The VSL Climbform System will generally achieve an optimal cycle of three days per four meter lift, however, due to the modular arrangement of the system, variable lift heights can be accommodated with relative ease up to a maximum lift height of six meters.

FOR MORE INFORMATION, PLEASE REFER TO THE VSL FORMWORK BROCHURE.
Stonecutter Bridge. Hong Kong
C215 High Speed RaiL Taiwan
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VSL BEARING SYSTEMS

Generally, structural bearings are required to connect different parts of a given structure, such as a bridge deck to piers and abutments. The most widely used structural bearings are reinforced elastomeric bearings and pot bearings. They are capable of transmitting forces while absorbing the structures deformations and rotations.

The strength of reinforced elastomeri bearings is limited by the shear properties of the elastomeric block, especially when compression, shear and bending occur at the same time. Pot bearings maximise the shear strength of the bearings elastomer by encasing it in a steel cylinder. Elastomeric and Pot bearings can be fixed, guided or free depending on design requirements.

VSL offers fixed pot bearings which permit movement in one or any direction.

Pot bearings for incrementally launched bridges have a dual function. First they provide low friction sliding surfaces over piers as the deck is pushed during construction. Thereafter, they become permanent bearings. A pot bearing serving these functions is shown ¡n the picture above. During construction, a fixing device avoids relative movement between the sliding plate and the pot cylinder.

The sliding plate is equipped with an upper stainless steel panel. This is followed by the insertion of neoprene-teflon pads during the launching operation to be carried out. The pads, upper stainless steel panel and fixing device are removed after launching. Finally the sliding plate is connected to a previously embedded steel plate in the deck.



VSL Bearing Replacement Works
Installation of VSL Pot Bearing
Bearing fabrication works
Pot baring type PU


FOR MORE INFORMATION, PLEASE REFER TO THE VSL BEARING BROCHURE.
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STRUCTURAL MONITORING

Monitoring should be a simple and economic activity, adapted to each of the specific parts of the structure depending on functional and risk analysis. VSL’s monitoring package is offered as an additional service to provide the client with longterm cost savings. It can be applied to structures and to cables (bridges, buildings) either as ground anchors, post-tensioning tendons, or stay cables. In-house R&D has placed emphasis on durability method, measurement and sensor configurations, thus allowing to both assess the actual condition of stay cable system components and predict subsequent evolution. The VSL full service monitoring package may be used to assess shrinkage, stress evolution and vibration of the concrete structure weather conditions, traffic, pollution; to send and to follow-up the behavior or the structure, optimise maintenance; to detect damage and confirm diagnosis of deterioration; to valifate and memorise know-how for future projects; to optimise life cycle cost of the structure.

As an additional service, the VSL DeMon system allows wireless connection from your office to any type of sensors on site through internet and wireless devices. The system provides real time, 24 hours a day, filtering of the data to detect events, to send an alarm and to analyse only significant events.
VSL load cell
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