P O S T- T E N S I O N I N G S T A Y C A B L E S GROUND A N C H O R S R E TA INED EAR T H H E AV Y L I F T I N G C L I M B F O R M B A R S Y S T E M S S T R U C T U R A LB E A R I N G S V S L C O N S T R U C T I O N S Y S T E M S VSL’ s special construction systems have been used throughout the world since 1956. They are technically proven and have earned a well-deserved reputation for their quality and reliability. This has led to VSL becoming a recognised leader in the field of special construction systems/methods and related engineering. Post-Tensioning is VSL’ s core business. Multistrand and monostrand systems are used in every area of concrete construction, where prestressing forces are introduced into the structure once the concrete has hardened. Complying with national and international standards, they are approved in every country where the use of post-tensioning requires official certification. The post-tensioning principle is also applicable to stay cables, external cables, as well as ground anchors using strand or bar systems. VSL’ s understanding of prestressing has also led to the development of the VSL Heavy Lifting system which provides safe and cost-saving solutions for lifting, lowering and horizontal jacking of large and heavy loads. This publication represents a summary of VSL’ s special construction systems and includes essential design and construction information. Technical data and dimensions of anchorages, cables and equipment are given in the annexe. “Schlund” Roundabout - Switzerland Grand Central Tower - South Africa Avignon Viaduct - France TThe Company 2 Further details concerning the use of the various construction systems can also be found in a number of technical publications available from your local VSL representative or any VSL office. VSL operates as a transnational group of companies. Its subsidiaries and licensees are organised into closely co-operating regional units. Our customers directly benefit from the continuing development of VSL’ s special construction methods and from the exchanges of information taking place within the VSL Network. This means that our customers have local access to all the resources and expertise provided by the VSL Group. VSL also provides a comprehensive set of professional services able to meet the specific requirements of a wide range of special construction engineering. VSL Companies are able to execute all works using VSL personnel and equipment. This involvement includes appropriate technical consultancy and support during planning and construction phases. VSL’ s services can include feasibility studies, preliminary designs and alternative proposals, as well as structural design assistance. These services aim to provide fully customised solutions adapted to customer requirements. We offer our customers the strength and flexibility of our world-wide network. Our goal is to be your privileged partner and help find the best-adapted solutions to your particular needs. 3 Wadi Leban Stay Cable Bridge - Saudi Arabia A4 Motorway - Poland Charles de Gaulle Bridge - Paris,France The VSL Multistrand system is characterised by the following features: l standardised tendon units using up to fifty-five 13-mm (0.5”) or 15-mm (0.6”) diameter s t r a n d s ; l wide selection of anchorage types; l steel or plastic PT-PLUSTM ducts; l cement or other types of grouting; l tendons manufactured on-site or in the factory; l no need to determine tendon length in advance; l simultaneous stressing of all strands in a tendon, with individual locking of each strand at the anchorage point; l s t ressing carried out in any number of phases; l simple and reliable equipment for installation, stressing and grouting. 4 MMultistrand Post -Te n s i o n i n g VSL Multistrand System Components VSL Anchorages Technical data and dimensions are given in the annexe. For reasons of clarity and simplicity, spirals are not shown in the pictures. However, they form an integral part of the anchorage and are required to control local zone stresses. For more detailed information, see V S L’ s Report Series on “Detailing for Post-Tensioning”. Our SO and SK anchorages, as shown on page 13, are standard for slab post-tensioning. They are also often used for bridges (transversal post-tensioning) and other structure s . 5 Grout connection Anchor head Wedges Strands Duct Bearing plate (casting) Stressing Anchorage: VSL Type Ec This compact and easy to handle anchorage system allows prestressing force to be transferred through two flanges. If necessary, the spiral can be replaced by suitably laid out orthogonal reinforcements. Equipped with an additional retainer plate, the Ec anchorage can also be used as a dead-end anchorage. Stressing Anchorage: VSL Type CS 2000 This revolutionary anchorage has a composite bearing plate (metal - high performance concrete) and is lighter, smaller and easier to handle. It comes in 3 different configurations: CS 2000 - STANDARD for normal applications, CS 2000 - PLUS using VSL’ s PT-PLUSTM duct system for enhanced corrosion protection or improved fatigue resistance, and CS 2000 - SUPER able to provide an electrically isolated tendon. Equipped with an additional retainer plate, the CS 2000 anchorage can also be used as dead-end anchorage. Grout tube Duct Sleeve Strands Wedges Anchor head Bearing plate (steel) Stressing Anchorage: VSL Type E The prestressing force is transferred to the concrete by a bearing plate. If necessary, the spiral can be replaced by suitably laid out orthogonal reinforcements. Equipped with an additional retainer plate, the E anchorage can also be used as a dead-end anchorage. Strands Wedges Anchor head Bearing plate Duct CStrumpetGrout connection Protection cap Coupler: 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. Coupler: VSL Type V This movable coupler is used for connecting to a cable that has already been installed but not stressed. The strands of the new cable are anchored using compression fittings positioned onto the coupling head of the previously installed cable. Intermediate Anchorage: VSL Type Z and ZU Intermediate anchorages are used for those tend o n s w h e re 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: l for pre s s u re shaft and pre s s u re tunnel ring tendons, avoiding the use of internal buttresses; l for silo and reservoir circular structure ring tendons, avoiding the use of external buttresses; l for transversal bridge deck prestressing where, for aesthetic reasons, external anchorage blockouts are undesirable; l for frame, arch and shell structure tension ties where there is no or limited access to end anchorages. The VSL type ZU intermediate anchorage has similar application possibilities as type Z. It is particularly adapted to small cable units in structures without dynamic loading. 6 Sleeve Coupling head V Tension ring Compression fittings with retainer plates Anchor head Z Retainer plate Wedges Duct Tension ring with anchors Grout tube Wedges Anchor head ZU Grout tube Wedges Bearing plate type Ec or E Tension ring Sleeve Coupling head K Duct Compression fittings Steel band MMultistrand Po s t - Te n s i o n i n g Dead-End Anchorage: VSL Type P This type of anchorage is used where the pre s t re s s i n g force has to be transferred to the structure at the far end of the tendon. It consists of a folded 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 can only be transferred to the concrete using a bearing plate, polyethylene tubes can be used to sheathe the strands between the end of the duct and the bearing plate. 7 U-plate Grout tube Duct Tension ring Seal P-plate Compression fittings Retainer plate Duct Tension ring Seal Grout tube Dead-End Anchorage: 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 by bond. The spiral (for 5-7 / 6-7 and larger units) and tension ring prevent inadmissible stresses due to deviated forces acting on the concrete. The rebar net at the anchorage end zone acts as a spacer for individual strands. Dead-End Anchorage: VSL Type U The transfer of the prestressing force is partially achieved by bonding the strands to the concrete, and partially by the U-shaped plate fixed to the concrete. The spiral and tension ring prevent inadmissible stresses due to deviated forces acting on the concrete. The anchorages can be used both vertically and horizontally. Bulbs Tension ring Grout tube Duct Seal Spacer Sheathing and corrosion protection Generally speaking, corrugated steel ducts with a minimum wall thickness of 0.25 mm are used. While workshop prefabricated cables normally use a flexible duct, a semi-rigid type is the solution most often used where cables are pushed or pulled through on site. However, the VSL PT-PLUSTM system with its corrugated duct and plastic coupler can provide a number of important advantages when compared with conventional ducts, such as: l greatly enhanced tendon corrosion protection; l improved tendon fatigue resistance; l reduced sensitivity to stray electric curre n t s ; l reduced duct friction coefficient; l the PT-PLUSTM system, when used with VSL CS and ECS anchorages, can be adapted to provide electrically isolated tendons (EIT). The PT-PLUSTM system is suitable for all applications but, given its specific characteristics, is best adapted to: l transverse tendons in bridge deck slabs and wherever tendons are close to the concrete surface; l railway bridges and other structureswith high fatigue loadings or subject to stray electric currents; l structures where severe corrosive environment may be expected; l tendons that need to be electrically monitore d t h ro u g h o u t the structure’s service life. 8 Dead-End Anchorage: 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 points. Dead-End Anchorage: 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 a n c h o r a g e . The strands, with compression fittings at their ends, are bonded to the load-transferring casting by a special cement grout. Once stressed, the cable over the anchorage is then grouted. Duct B Duct A Grout tube MMultistrand Post -Te n s i o n i n g Selected design considerations Duct spacings and covers When determining minimum spacing and concrete cover requirements, reference should be made to applicable standards and recommendations. Tendon supports Recommended spacing: Standard steel ducts 0.8 to 1.2 m PT-PLUSTM plastic ducts 0.8 to 1.0 m 9 Minimum radius of tendon curvature Minimum tangent length Minimum breaking load of tendon (MN) Minimum radius of tendon curvatures and minimum tangent length for internal bonded tendons Tendon force losses The effective prestressing force at a specific place and time differs from the initial prestressing force. There are several reasons for this. Significant factors include: l friction losses due to the curvature of the tendon; l concrete shrinkage and creep; l relaxation of the prestressing steel; l draw-in of the wedges during lock-off. Friction losses along the tendon can be determined using the following formula: Px = Po.e-(µα + kx), in which: x = distance from stressing end (in meters); Px = prestressing force at x; Po = prestressing force at stressing end; µ = friction coefficient; α = sum of all angular deviations (in radians) over the distance x; k = wobble friction coefficient due to minor unintentional tendon curvatures (installation tolerances). The µ and k friction coefficients can vary fairly widely and depend upon several factors, including: the nature and surface condition of the prestressing steel; the type, diameter and surface condition of the duct, and the installation method. The following values may be assumed for design: - tendon in standard steel ducts: µ = 0.2 (range: 0.16 to 0.22) k = 0.001 (range: 0.0008 to 0.0012) - tendon in PT-PLUSTM plastic ducts: µ = 0.14 (range: 0.12 to 0.15) k = 0.001 (range: 0.0008 to 0.0012) To calculate losses due to concrete shrinkage and creep, reference should be made to the technical documents and standards applicable to each pro j e c t . The relaxation of the prestressing steel depends primarily on the type of steel (relaxation class), the extent of the prestressing, and the temperature. For the low relaxation strands commonly used today, maximum loss is 2.5% after 1,000 hours at 20°C with an initial stressing at 70% of the nominal tensile strength. Further information can be found in the relevant prestressing steel standards and manufacturers’ literature. Independent of the jack or tendon type, a loss of approximately 6 mm due to wedge draw-in occurs at lock-off. If necessary, compensation can be provided by appropriate procedures. Stressing The unique feature of the VSL Post-Tensioning system lies in its special wedge locking procedure. The wedges always remain in contact with the strands during the stressing operation. As the pressure in the jack is released, the wedges automatically lock in the conical holes of the anchor head. Grouting VSL grouting equipment includes a combined mixer and pump unit. Grouting is carried out as soon as possible after stressing. For long cables, and in the case of electrically isolated tendons, vacuum-aided grouting is highly recommended. 10 Placing of anchor head MMultistrand Po s t - Te n s i o n i n g Positioning of jack Grouting of tendon Placing of anchor head and we d g e s Positioning of jack Stressing Seating of wedges Stressing,measuring,seating of wedges 11 Construction Sequence Today’s building owners and designers need to provide a high level of structural flexibility to meet changing user requirements. Post-tensioning provides greater spans with reduced structural beam depths, resulting in larger column-fre e areas. As a result, internal layouts are not dictated by tight column grids. Positive deflection and crack c o n t rol 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, minimising site congestion. Most importantly, there is the quality and service p rovided by VSL’ s specialised high-performance teams. The VSL Post-Tensioning Slab system has been used in many prestigious buildings and structures. The system uses up to five strands contained in flat-shaped ducting, and anchorages. 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. AL Faisaliah Building - Riyadh,Saudi Arabia Placing tendons Concreting Stressing Grouting Dah Chong Hong Building - Hong Kong BBonded Slab Post-Tensioning Selected design considerations l Spacing of tendon supports: 0.75 to 1.2 m (conventional steel ducts) 0.75 to 1.0 m (PT-PLUSTM plastic ducts) l Minimum curvature radius: 2.5 m (vertical profile) 6.0 m (horizontal profile) l Min. straight length at anchorage: 0.75 m l A wedge draw-in of approximately 6 mm occurs at lock-off l Friction losses can vary fairly widely from one tendon to another and from one structure to another. This depends on factors such as surface condition of strands, duct types and surface condition, material properties, installation methods and on-site workmanship. Generally speaking, the following friction parameters can be used. • Tendons in standard steel ducts: µ = 0.20 (-) (range: 0.16 to 0.22) k = 0.001 (m-1) (range: 0.0008 to 0.0012) • Tendons in plastic ducts: µ = 0.14 (-) (range: 0.12 to 0.15) k = 0.001 (m-1) (range: 0.0008 to 0.0012) The PT slab method allows designers to reduce building heights or to increase free heights between floors. 12 Free height Free height Free height Free height Height saving Traditional Design PT Slab Design BBonded Slab Post -Tensioning 13 Stressing Anchorage VSL Type SO Tension ring Seal P-plate Compression fittings Retainer plate Dead-End Anchorage VSL Type H Coupler VSL Type SK Dead-End Anchorage VSL Type P Grout tube Wedges Strands Recess former Flat duct Anchorage body Trumpet Grout tube Tension ring Seal Bulb Spacer Flat duct Grout tube Sleeve Compression fittings Coupling head SK Strands Flat duct Trumpet Bearing plate Steel band Wedges Flat duct The VSL Monostrand system has advantages similar to those of the VSL Bonded Slab Post-Tensioning system. The VSL Monostrand system uses 15 mm (0.6'') diameter strands. The strands are given a coating of permanent corrosion-preventing grease and are enclosed in an extruded plastic sheath. The grease and plastic provide double corrosion protection, as well as preventing any bonding between the strands and the surrounding concrete. The plastic sheath is usually in polyethylene or polypropylene with approximately 1 mm wall thickness. The monostrands are installed either singly or in bundles of two, three or four. Each strand is individually anchored, stressed and locked-off. To ensure continuous corrosion protection, special sleeves are used to join the sheaths to the anchorages and the anchorages are provided with a protective cap. Monostrands feature factory-applied corrosion protection, very low friction losses, and permit the structural depth to be fully utilised. These light, flexible monostrands can be easily and rapidly installed, and because there is no grouting, they usually lead to economical solutions. In design, the different post-cracking behaviour of unbonded versus bonded systems should be considered. Detailed information is given in V S L’ s " P o s t - Tensioned Slabs" publication. With certain adaptations, the VSL Monostrand system can also be used for post-tensioning masonry walls. 14 Monostrand stucture Monostrands specifications: l 15-mm (0.6'') diameter strand in accordance with the concerned prestressing steel standards. l External diameter of the plastic sheath: approximately 18 mm. l Permanent corrosion-preventing grease and plastic sheath in accordance with FIP or PTI recommendations. MMonostrand Post -Tensioning CTC Building - Santiago, Chile 15 Monostrand 2 Sleeve Monostrand 1 Coupling body Coupling head and threaded coupling Installation piece Wedges Monostrand Sleeve Anchorage body (casting) Recess former Installation nut Sleeve Stressing Anchorage: VSL Type S-6 Dead-End Anchorage: VSL Type SF-6 Stressing Jacks Coupler: VSL Type SK-6 Twin ram jack DKP-6 Centre hole jack ZPE-23FJ Recommended design va l u e s Spacing of tendon supports: 0.6 to 1.5 m Minimum curvature radius: 2.5 m The following friction cœfficients may be assumed: µ = 0.06 (_) k = 0.5 10-3 (m-1) For standard building slabs, this results in a tendon force loss of approximately 2.5% per 10 m length of monostrand. Reinforcement of the anchorage zone In addition to the slab reinforcement required by the design, additional reinforcement is necessary in the force distribution zone behind each anchorage. Details should be established by the project engineer. The sketch shows an arrangement which has proved itself in practice. Anchorage boby (casting) Monostrand Sleeve Closure cap External post-tensioning is well adapted to bridges due to the resulting savings in construction costs 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: l strand bundle; l polyethylene ducts; l standard multistrand anchorages, and special anchorages permitting easy tendon re p l a c e m e n t ; l grouting compound. 16 Boulonnais Viaducts - France Bois de Rosset Viaduct - Switzerland EExternal Post-Tensioning VSL External Post-Tensioning System Components Stressing anchorage Strand bundle and sheathing Stressing anchorage 17 Saddles at points of deviation A saddle at a point of deviation consists of: l a structural element capable of carrying the loads exerted by the tendon in the deviation zone; l a part ensuring the geometry of the deviation. Globally, a saddle at a point of deviation must satisfy the following requirements: l withstand both the longitudinal and transversal forces that the tendon applies to it and transmit these forces to the structure; l e n s u re, without unacceptable angular breaking, the connection between two straight tendon sections; l unless otherwise stipulated in the contract, enable removal of the tendon without traumatic effect on the structural elements; l withstand movements of external tendon during stressing without compromising the tendon's corrosion protection system. When designing saddles it is important to consider the following: Various solutions have been used in practice, as shown on the sketch. In most cases, saddles consist of a pre-bent steel tube cast into the surrounding concrete or attached to a steel structure by stiffening plates. The connection between the free tendon length and the saddle must be carefully detailed in order not to damage the prestressing steel by sharp angular deviations during stressing and in service. It is also important that the protective sheathing be properly joined. If tendon replacement is a design requirement, the saddle arrangement must be chosen accordingly, i. e. double sheathing as shown on alternative (3) of the sketch. Minimum tendon radii: Minimum tendon radii as recommended in Table 1 must be respected in order to avoid damage to the prestressing steel and the plastic sheathings, as well as to the outer tubing. It is well-established that friction problems may occur if tendon radii are too small. Tendon size (VSL tendon unit) Minimum radius (m) up to 5-19 or 6-12 2.50 up to 5-31 or 6-19 3.00 up to 5-55 or 6-37 4.00 Table 1: recommended minimum tendon radii Various saddle arrangements 18 VSL Stay Cable System SSI 2000 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: l a tendon formed from multiple and parallel 15-mm (0.6”) dia. high tensile 7-wire steel s t r a n d s ; l a greased or waxed extruded plastic coating to each strand; l an outer thick-walled plastic stay pipe; l factory prefabricated anchorages. The system features are as follows: l 200 MPa high fatigue resistance at 45% of tendon capacity over 2,000,000 load cycles; l high degree of corrosion resistance using multi-layer corrosion protection; l an extruded coating providing excellent strand corrosion protection during construction; l individual strand encapsulation and sealing in anchorages; l easy installation of the strands into the erected stay pipe (single strand installation); l all strands are parallel with no risk of twisting; l single strand stressing; l no requirement for on-site cable grouting; l easy tendon force monitoring and adjustment throughout the cable's service life; l ability to remove and replace individual strands without dismantling the installed anchorages, or the entire cable at any time; l system adapted for the future installation of an anti-vibration damper. S Bundle of monostrands HDPE stay pipe Grease or wax PE sheath Strand Huerfanos Footbridge - Chile Stay Cables Transition pipe with individual strand protection Guide pipe Dead-end anchorage Centering elastomeric device Individual VSL monostrand and stay pipe Anchorage head and ring nut Compactness The reduced size of the anchorage components allows for easy installation and savings in the cost of structural works. Aesthetics l using coloured co-extruded stay pipes, different colours can be obtained; l vibration damping devices can be placed inside guide pipes or stay pipes. Dynamic stability of the cabl e s l stay pipes can be equipped with external helical ribs to suppress rain-wind induced vibrations; l the stay cable system is adapted for the future installation of anti-vibration dampers. Durability A high degree of corrosion protection: l each strand is individually protected not only in the stay pipe, but also in the transition part of the anchorage; l individual anchorage sealing joints protect each strand not only in service, but also during bridge erection; l 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 exposure of the entire cable, VSL’ s Stay Cable system reduces the potential exposure to a single strand. Reduced maintenance costs l easy corrosion control of anchorage components; l good access to vibration damping systems. Stay cable installation l system optimised for strand-by-strand installation, with easily handled, lightweight equipment and reduced construction loads on the bridge during construction. 19 Val de Rennes - France Uddevalla Stay Cable Bridge - Sweden 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. VSL offers all of these alternatives and can support a full anchor material supply service (anchors and accessories) with back-up including design services, advice, consultancy, testing, installation, tensioning and site supervision. VSL has obtained ISO 9002 Quality Approval for its technology. The construction of the VSL Strand Anchor depends on the type of application (rock or soil), the design, the corrosiveness of the environment, the pre s e n c e of stray electrical currents and the intended service life. While temporary ground anchors require limited or no corrosion protection, permanent ground anchors (with a service life exceeding two or three years) need to have a comprehensive permanent corrosion protection system. The anchor construction can be adapted to a wide range of specific requirements. Anchorages can be designed to allow the anchor force to be adjustable, releasable or be used as a monitoring anchor. VSL’ s range of anchors extends from permanent anchors that allow electrical resistance measurements to be taken to check the integrity of the encapsulation during the entire service life, to temporary anchors that can be easily extracted after use. VSL also offers load cells that allow the anchor performance to be monitored. The anchor shown on this page represents a typical permanent strand anchor with a thick walled polyethylene encapsulation acting as a protective barrier against corrosion. Temporary anchors are similarly constructed except that, being designed for a shorter service life, corrosion protection requirements are usually less demanding. The anchor is not normally encapsulated and can take the form of a bundle of bare strands in contact with grout over the bond length of the anchor. Both types of anchor systems comprise the anchor with a bearing plate, anchor head and wedges. 20 GGround Anchors spacer tightly sealed, strong protective cap corrugated polyethylene sheath in bond length bare strand spreader Alternative anchorages Type ER (adjustable anchorage) / EA l identical to type EF, but with threaded anchor head and ring nut; l depending on the height of the ring nut, the anchorage permits anchor force adjustments; l minimal strand projection for load checks / force adjustments; l complete detensioning possible with slightly different features (type EA). Type EG (control anchorage) l used for periodical load checks with removable or permanent load cell; l load checks using a lift-off jacking system. Type EF (electrically isolated) l same features as basic EF type but allows monitoring of integrity by measuring electrical resistance; l electrical isolation features can be applied to all other anchorage types as well. 21 grout inlet smooth polyethylene sheath in free length polyethylene coated and greased strand with tensile / yield strength acc. to local requirements transition from free length (smooth polyethylene sheath) to bond length (corrugated polyethylene sheath) Type EF (basic anchorage) l generally used for service anchors; l force cannot subsequently be adjusted; l minimal strand projection allows load checks using a lift-off jacking system. Bajikrachen Rock - Switzerland protective cap Electrically Isolated Anchors These anchors use tight PE encapsulation combined with an electrically non-conductive anchorage isolation. The integrity of the anchor can be checked thro u g h o u t its service life using electrical resistance measure m e n t s . Force measurements VSL is able to provide specially developed load cells for temporary and permanent control anchors, as well as for permanent surveillance anchors. The following three types are available: l type G hydraulic load cell, permanently installed for control anchors; l type GW hydraulic load cell, used as a removable load cell allowing several permanent anchors to be measured from time to time by moving the cell from one anchor head to the other; l type D electrical load cell, providing supervision of permanent and temporary anchors and allowing continuous load measuring using either a direct or remote reading system. All load cell types are fully compatible with the VSL Anchor system. Our scope of services includes consultancy, supply and installation of load cells, as well as control anchor readings. Anchor load checks VSL performs periodic anchor load checks using suitable equipment and competent personnel. This is carried out by lift-off checks using VSL jacks or the required type GW load cells. These standard load checks can be carried out on type EG, ER and EA anchorages. With our specially developed APP jacks, we are in the unique position to carry out lift-off checks on anchors with type EF anchorages where the anchor head has no thread and where pro j e c t i n g strands were cut after installation. The jack has a mechanism to grip standard size anchor heads with up to twelve 0.5”-dia. strands or seven 0.6”-dia. strands. This allows clients to carry out load checks in situations that, in the past, had been particularly difficult. Anchor extraction It is often undesirable to leave temporary anchors in the ground, particularly in urban areas where they normally extend into adjacent property. The method developed by VSL for extracting the free anchor length is based on a specially designed mechanism located at the point where the strand is disconnected. VSL has a long tradition in this special technique, with thousands of anchors successfully extracted. 22 Securing a slope Strengthening of a gravity dam GGround Anchors 23 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 earth 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 construction 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 reinforcement, this is achieved by the development of passive resistance on the projected area of the mesh crossbars, which in turn transfers load into the longitudinal bars. 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 is particularly straightforward. A five-man crew using standard construction equipment can place an average of 75 m2 - and as much as 140 m2 - of wall per shift. Complete services VSL advises customers and their consulting engineers during the feasibility stages of projects, and prepares preliminary design and cost estimates, as well as detailed designs, drawings and specifications. The company also assists contractors with the pricing of tenders, and provides quotations during tender stages. Execution of the on-site project can be tailore d to suit the customers' requirements, from a supply only arrangement to a full sub-contract agreement. Complete flexibility VSoL system concrete facing panels are available in a wide range of shapes, textures and colours. Because local materials are used in the production of these precast panels, the visible exposed surface can easily be coloured to match the natural surroundings. Raised relief, sandblasted finish, exposed aggregate, and conventional smooth face c o n c rete re p resent just a few of the available standard retained earth panel finishes. Other facing systems, such as modular blocks, and mesh are also available for both permanent and temporary structures. Eje Prat Road Walls - Chile F5 Freeway - Australia VVSoL: VSL Retained Earth System Architectural Panels 24 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 specialised hydraulic lifting equipment is designed to provide the highest level of reliability, and VSL field services are based on a total commitment to safety. Flexibility Our equipment includes a large number of hydraulic strand units, jacks, pumps, control units, monitoring devices and modular lifting / jacking frames, giving us the capacity to perform virtually any project requiring lifting, lowering or horizontal jacking. The VSL Service Package Our approach is flexible, and the range of our services is tailored to the specific project requirements. They include: l feasibility studies and preliminary consultation; l project design and planning; l design, manufacture, and supply of special equipment; l leasing of VSL equipment and execution of work. Malaysia / Singapore Second Crossing Vereina Tunnel - Klosters,Switzerland Soccer Stadium - Torino, Italy HHeavy Lifting Proven equipment for handling heavy loads The 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 contro l s . 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 piston’s downward movement, the strands are 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 consists of 7-wire prestressing steel strands with a 15-mm nominal diameter. 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. P re s s u re control devices allow forces to be monitore d at all times. The movement speed varies according to the project and, if required, can be in excess of 20 m / hour. C o n t rol 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. 25 Normandie Bridge - France Burj Al Arab Hotel - Dubai Autofonçage® and Autoripage® are methods allowing roads and railways to be crossed rapidly with minimum traffic disruption. The Autoripage® system is used when the road or track to be crossed can have its traffic interrupted for a period not exceeding 24-72 hours. This period depends on the extent of the associated works. The actual slide duration is typically about 6 hours. The Autofonçage® system consists of passing a p recast concrete underpass through an embankment, generally bearing a railway or a motorway, without interrupting the traffic. This can be accomplished either by using two half structures pulled together beneath a road or a railway, or as a single box structure jacked into position from one side only. The first Autofonçage® operation was carried out near Paris in 1984 and since then the system has been used successfully in a number of European countries. VSL has worked closely on projects with SNCF (French Railways), SNCB (Belgian Railways), Railtrack (British Rail) and Portuguese Railways. The sliding operation uses motive units of the VSL strand system. The equipment is operated by VSL and provides a continuous, rapid, accurate and reliable pulling operation. The displacement of the concrete structure displays information about the structure position on monitoring screens placed alongside the system operators. This system can be used for structures weighing in excess of 5,000 t., and the accuracy of the final positioning is approximately one centimetre in all three axes. Considerable improvements have been made to the system over the last decade and owners, engineers and contractors can now benefit from these developments that have led to work being carried out rapidly, efficiently and economically. 26 Troyes West Diversion - France “Francilienne” Highway Underpass - Louvres,France AAutofonçage® and Autoripage® Methods A26 - Yvetot,France 27 VSL has been active in climbforms for over 15 years, first in Australia, then Asia and, more recently, Europe. The system has consistently proven itself over this period. Constant developments and improvements made following suggestions from contractors have led to VSL Climbform achieving the high level of standards needed to meet today‘s requirements. The system is particularly adapted to the construction of high-rise building cores. VSL Climbform system The 6-m high VSL Climbform has three platform levels, and the formwork panels hanging from the external frame and internal platforms permit pours over a height of 4.2 m. The external frame is assembled from standardised steel components and others components which are specific to each project and designed by our Technical Centres. The internal steel platforms, incorporating the formpanel hooks and rollers, are specifically designed and manufactured for each project - guaranteeing accurate and economic assembly operations. The climbform is raised using a number of hydraulic jack systems, including telescopic jacks, climbrams, long stroke jacks, and rod jacks. It takes approximately one hour to raise the climbform system up to the next level. The external frame construction cycle depends on several factors but generally takes around 3 to 4 days per level. Advantages VSL Climbform permits an excellent production rate. It permits the accurate placing of door frames, openings, blockouts and cast-in components. VSL Climbform also offers the direct placing of prefabricated reinforcement cages. Another advantage lies in the safety of the climbform. This is achieved through the use of wide platforms and the methods used to provide the best possible access to the different framework components. VSL Package The VSL service package generally includes: l feasibility studies and preliminary consultation and pricing; l tender design and planning; l design, manufacture and supply of equipment; l leasing of VSL equipment, training of site-staff, supervision of the works for the first few levels, followed by dismantling operations. CClimbform Coeur Défense - Paris,France Central Plaza - Hong Kong Bar technology VSL has been manufacturing and designing bars for the Construction Industry since 1971. VSL has now decided to widen its range of bar products by adding an extensive list of hot-rolled high performance products to the original VSL cold-rolled bars. VSL’ s new product line complies with most international standards, including DIN, BS, ASTM, etc. VSL Bar systems are specifically designed to suit all geotechnical applications as well as civil works and building applications. 28 B Lainzer Tunnel - A u s t r i a Product reference Y1030H26.5R-R Y1030H32R-R Y1030H36R-R Y 1 0 3 0 H 2 6 . 5 R - R( * ) Y1030H32R-R(*) Y1030H36R-R(*) Y1030H40R-R(*) Y 1 0 5 0 H 1 8 R - R( * ) ( * * ) Y 1 0 5 0 H 2 6 R - R( * ) Y 1 0 5 0 H 3 2 R - R( * ) Y 1 0 5 0 H 3 6 R - R( * ) Y 1 0 5 0 H 4 0 R - R( * ) ( * * ) Y1230H26.5R-R Y1230H32R-R Y1230H36R-R Diameter (int. / ext.) d/da (mm)/(mm) 26.5/30 32/36 36/40 26.5/30 32/36 36/40 40/44 18/21 26/29 32/36 36/40 40/44 26.5/30 32/36 36/40 Cross section area A (mm2) 551 804 1,020 551 804 1,020 1,257 254 531 804 1,020 1,257 551 804 1,020 Strength Yield/tensile f0.1k/ftk (MPa)/(MPa) 835/1,030 835/1,030 835/1,030 900/1,030 900/1,030 900/1,030 900/1,030 950/1,050 950/1,050 950/1,050 950/1,050 950/1,050 1,080/1,230 1,080/1,230 1,080/1,230 Yield load F0.1k (kN) 460 671 850 496 724 916 1,131 240 500 760 960 1,190 595 868 1,099 Tensile load Ftk (kN) 568 828 1,049 568 828 1,049 1,295 270 560 850 1,070 1,320 678 989 1,252 Weight G (kg/m) 4.48 6.53 8.27 4.48 6.53 8.27 10.2 2.06 4.31 6.53 8.27 10.2 4.48 6.53 8.27 Product reference B500H20R-L B500H25R-L B500H28R-L B500H32R-L B500H40R-L B500H50R-L S555H63.5R-L S670H18R-R S670H22R-R S670H25R-R S670H28R-R S670H30R-R S670H35R-R S670H43R-R S680H57.5R-R S680H63.5R-R Diameter d/da (mm)/(mm) 20/23 25/28 28/32 32/36 40/45 50/55 63/68 18/20 22/25 25/28 28/31 30/33 35/38 43/47 57.5/61 63.5/68 Cross section area A (mm2) 314 491 616 804 1,260 1,960 3,167 250 380 491 616 720 962 1,466 2,597 3,167 Strength Yield/tensile f0.2k/ftk (MPa)/(MPa) 500/550 500/550 500/550 500/550 500/550 500/550 555/700 670/780 670/780 670/780 670/780 670/780 670/780 670/780 680/850 680/850 Yield load F0 . 2 k (kN) 160 245 310 405 630 980 1,760 160 240 320 400 480 640 980 1,760 2,150 Tensile load Ftk (kN) 175 270 340 440 690 1,080 2,215 185 280 370 460 560 750 1,130 2,200 2,600 Weight G (kg/m) 2.47 3.85 4.83 6.31 9.87 15.4 24.85 1.96 2.98 3.85 4.83 5.65 7.55 11.51 20.38 24.86 Bar Systems (*) Water cooled fabrication process (**) Availability upon request 29 Rock Bolts l stabilising galleries during excavations l stabilising unstable rock/soil l flexible attachment thanks to the high level of steel elongation/ductility l a range of different anchoring systems l grouted, resin anchors, expansion shells l a large number of special accessories Soil Nails l slope stabilisation l retaining wall strengthening l flexible attachment thanks to the high level of steel elongation/ductility, permitting soil movement l permanent and temporary use Micropiles l foundations (compressive load) l tensile piles (tensile load) l ideal for alternating tensile and compressive loadings l securing of building foundation walls, embankments, compacted soil areas, high-rise buildings, structures in seismic areas Ground Anchors l tie-backs l retaining walls l stabilising deep excavations, anchoring tower cranes l permanent and temporary use Tie Rods l tie-backs l retaining walls l sea walls l permanent and temporary use Reinforcements l DIN 488 accreditation for B500 steel quality l convenient for coupling through the use of continuous threading l efficient coupling solution in areas where there are too many steel components l alternative to shear studs Stress Bars l high performance for forces ranging from 270 to 1,320 kN l prestressed/post-tensioned concrete structures l strengthening of buildings l temporary prestressing and bracing Westbound Off-Ramp to Western A rterial Road - A u s t r a l i a Form Ties l same production quality level as high grade stress bars l additional steel qualities, e.g. St 1,000/1,100 (weldable, high ductility, suitable for low temperatures), S850/900 steel with cold-rolled thread l accessories to suit all assembly situations G e n e r a l l y, 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 plain or reinforced elastomeric bearings, and pot bearings. They are capable of transmitting forces while absorbing the structure’s deformations and rotations. The strength of reinforced elastomeric 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 bearing’s elastomer by encasing it in a steel cylinder. 30 l TOP PLATE Quality steel St37 or St52according to DIN 17.100 l Stainless steel according to AISI 304 l LUBRICANT Silicone grease type 300 l P.T.F.E. P.T.F.E. pad with dimples accordingto ASTM D1457-91a Type 1Grade 2 BS 3784 Grade A l GUIDE Quality steel St37 or St52 according to DIN 17.100 l EXTERNAL SEALING RING Spongy neoprene l PISTON Quality steel St37 or St52 according to DIN 17.100 l INTERNAL SEALING RING Double gasket brass ring l ELASTOMER PAD Natural rubber accordingto AASHTO 50Sh±5 Pot bearing Type PU SStructural Bearings 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 for the completed bridge. A pot bearing serving both functions is shown in 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 between the deck and structural bearings which allows 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. l POT (STEEL RING + BASE PLATE) Quality steel St37 or St52 according to DIN 17.100 l ANCHOR SOCKETS Galvanized bolts Steel CK35 according to DIN 17.200 Pot bearings for incrementally launched bridges Pot bearing for incrementally launched bridges l DU-metal The Company 2 Multistrand Post-Tensioning 4 Bonded Slab Post-Tensioning 11 Monostrand Post-Tensioning 14 External Post-Tensioning 16 Stay Cables 18 Ground Anchors 20 VSoL: VSL Retained Earth system 23 Heavy Lifting 24 Autofonçage® and Autoripage® methods 26 Climbform 27 Bar Systems 28 Structural Bearings 30 PHOTO CREDIT: Desair-Foto, Photo Gasser, Y. Chanoit, Bouygues’ photo bank Saudi Archirodon, Dar-Al-Handasah, X. Your solution network Australia / Pacific territories REGIONAL OFFICE VSL Pre s t ressing (Aust.) Pty. Ltd. 6 Pioneer Avenue THORNLEIGH, NSW 2120 AUSTRALIA Phone: +61 - 2 - 9484 59 44 Fax: +61 - 2 - 9875 38 94 AUSTRALIA - Queensland VSL Pre s t ressing (Aust.) Pty. Ltd. GEEBUNG Phone: +61 - 7 - 326 564 00 Fax: +61 - 7 - 326 575 34 AUSTRALIA - New South Wa l e s VSL Pre s t ressing (Aust.) Pty. Ltd. THORNLEIGH Phone: +61 - 2 - 948 459 44 Fax: +61 - 2 - 987 538 94 AUSTRALIA - S o u t h e rn Division VSL Pre s t ressing (Aust.) Pty. Ltd. NOBLE PARK Phone: +61 - 3 - 979 503 66 Fax: +61 - 3 - 979 505 47 GUAM Structural Technologies Inc. TUMON Phone: +67 - 1 - 646 80 10 Fax: +67 - 1 - 646 80 60 North America LBFosterCy. SAN DIEGO, CA Phone: +1 - 619 - 688 - 2400 Fax: +1 - 619 - 688 - 2499 VStructural Llc. Regional Office B A LTIMORE, MD Phone: +1 - 410 - 850 - 7000 Fax: +1 - 410 - 850 - 4111 DALLAS, TX VStructural Llc. Phone: +1 - 972 - 647 - 0200 Fax: +1 - 972 - 641 - 1192 DENVER, CO VStructural Llc. Phone: +1 - 303 - 456 - 9887 Fax: +1 - 303 - 456 - 9796 WASHINGTON, DC VStructural Llc. Phone: +1 - 703 - 451 - 4300 Fax: +1 - 703 - 451 - 0862 We s t e rn Europe, Africa and Latin America REGIONAL OFFICE L’Odyssée - Bât. A 2-12 Chemin des Femmes 91886 MASSY Cedex FRANCE Phone: +33 - 1 - 69 19 43 00 Fax: +33 - 1 - 69 19 43 01 ARGENTINA VSL Sistemas Especiales de Construcción Argentina SA BUENOS AIRES P h o n e : +54 - 11 - 4326 - 06 09 Fax: +54 - 11 - 4326 - 26 50 BELGIUM NV Procedes VSL SA BERCHEM P h o n e : +32 3 230 36 34 Fax: +32 3 230 89 65 CHILE VSL Sistemas Especiales de Construcción SA SANTIAGO Phone: +56 - 2 - 233 10 81 Fax: +56 - 2 - 233 67 39 GREAT BRITAIN VSL Systems (UK) Ltd BUCKS Phone: +44 - 1 - 480 860 990 Fax: +44 - 1 - 480 861 092 GREECE VSL Systems A/E ATHENS Phone: +30 - 1 - 363 84 53 Fax: +30 - 1 - 360 95 43 MEXICO VSL Corporation Mexico S.A de C.V MEXICO P h o n e : +52 - 5 - 341 25 87/31 86 F a x : +52 - 5 - 396 84 88 NETHERLANDS VSL Benelux B.V AT LEIDEN Phone: +31 - 71 - 576 89 00 Fax: +31 - 71 - 572 08 86 NORWAY VSL Norge A/S STAVANGER Phone: +46 - 87 - 53 02 50 Fax: +46 - 87 - 53 49 73 PORTUGAL VSL Sistemas Portugal SA. S. DOMINGO DERANA P h o n e : +351 - 21 - 445 83 10 Fax: +351 - 21 - 444 63 77 SOUTH AFRICA VSL Systems South Africa (Pty) Ltd. KYA SAND Phone: +27 - 11 - 708 21 00 Fax: +27 - 11 - 708 21 20 SPAIN CTT Stronghold BARCELONA Phone: +34 - 93 - 200 87 11 Fax: +34 - 93 - 209 85 90 SWEDEN Internordisk Spännarmering AB STOCKHOLM Phone: +46 - 8 - 753 02 50 Fax: +46 - 8 - 753 49 73 North East Asia REGIONAL OFFICE VSL North East Asia 3/F Stelux House 698 Prince Edward Road East San Po Kong / Kowloon HONG KONG Phone: +852 - 2590 22 22 Fax: +852 - 2590 95 93 HONG KONG VSL Hong Kong Ltd. San Po Kong / Kowloon Phone: +852 - 2590 22 88 Fax: +852 - 2590 02 90 JAPAN VSL Japan Corporation TOKYO Phone: +81 - 3 - 3346 - 8913 Fax: +81 - 3 - 3345 - 9153 KOREA VSL Korea Co. Ltd. SEOUL Phone: +82 - 2 - 553 8200 Fax: +82 - 2 - 553 8255 MAINLAND CHINA Heifei VSL Engineering Corp. Ltd. ANHUI PROVINCE Phone: +86 - 551 - 557 6008 Fax: +86 - 551 - 557 6018 PHILIPPINES VSL Philippines Inc. MANDALUAYONGCITY Phone: +632 638 76 86 / 87 Fax: +632 638 76 91 TAIWAN VSL Taiwan Limited TAIPEI Phone: +886 - 2 - 2759 6819 Fax: +886 - 2 - 2759 6821 VIETNAM VSL Representative Office HANOI Phone: +84 - 4 - 8245 488 Fax: +84 - 4 - 8245 717 South East Asia REGIONAL OFFICE VSL Singapore Pte. Ltd. 75 Bukit Timah Road 04-08 Boon Siew Building Singapore 229833 SINGAPORE Phone: +65 336 29 23 Fax: +65 337 64 61 BRUNEI VSL Systems (B) Sdn. Bhd. BRUNEI DARUSSALAM Phone: +673 - 2 - 380 153 - 381 827 Fax: +673 - 2 - 381 954 INDIA VSLIndia Representative Office CHENNAI Phone: +91-44 859 2538 / 39 Fax: +91-44 859 2537 INDONESIA PT VSL Indonesia JAKARTA Phone: +62 - 21 - 570 07 86 Fax: +62 - 21 - 573 12 17 MALAYSIA VSL Engineers (M) Sdn. Bhd. KUALA LUMPUR Phone: +603 - 242 47 42 Fax: +603 - 242 93 97 SINGAPORE VSL Singapore Pte. Ltd. SINGAPORE Phone: +65 - 336 29 23 Fax: +65 - 337 64 61 THAILAND VSL (Thailand) Co. Ltd. B A N G K O K Phone: +66 - 2 - 237 32 88/89/90 F a x : +66 - 2 - 238 24 48 Central East Europe and Middle East REGIONAL OFFICE VSL (Switzerland) Ltd Bernstrasse 9 Lyssach - CH 3421 SWITZERLAND Phone: +41 - 34- 447 99 11 Fax: +41 - 34- 447 99 65 AUSTRIA Universale GSB VIENNA Phone: +43 - 1 - 878 170 Fax: +43 - 1 - 878 17 782 CZECH REPUBLIC VSL Systemy (CZ) s. r. o. PRAGUE Phone: +420 - 2 - 67 07 24 20 Fax: +420 - 2 - 67 07 24 06 GERMANY VSL Systems GmbH BERLIN Phone: +49 30 53 006 0 Fax: +49 30 53 546 37 POLAND VSL Polska Sp. z o.o. WARSAW Phone: +48-22 817 84 22 Fax: +48-22 817 83 59 SWITZERLAND VSL (Switzerland) Ltd. LYSSACH Phone: +41 - 34 - 447 99 11 Fax: +41 - 34 - 445 43 22 UNITED ARAB EMIRATES VSL Middle East Office DUBAI Phone: +971 - 4 - 28 20 803 Fax: +971 - 4 - 28 29 441 France VSL France S.A. EGLY Phone: +33 - 1 - 69 26 14 00 Fax: +33 - 1 - 60 83 89 95 HEADQUARTERS VSL International Ltd. Bernstrasse 9 - LYSSACH - CH 3421 - Switzerland Phone : 41 - 34 - 447 99 11 - Fax : 41 - 34 - 445 43 22 http:\\www.vsl-intl.com