01
Section Analysis
Spans, loads and anchorage layout are assessed against post-tensioning requirements.
Post-Tensioning
Solutions
OUR PROCESS
Post-tensioning process
02
Quotation
Tendons, ducts and stressing equipment are specified in the post-tensioning package.
03
Prestress Design
Prestressing force and losses are calculated in the post-tensioning design.
04
Detailing
Duct, anchorage and grouting details are drawn up.
05
Preparation
OHS measures, the stressing area and equipment are mobilised to site.
06
Stressing
Post-tensioning tendons are stressed under control, with every stage recorded.
07
Handover
The stressing report and anchorage protection are handed over to the operator.
EXECUTION
Post-tensioning with
controlled prestress
01Steel & Erection
Analysis
The need for post-tensioning in a bridge, silo or wall section is established using a load model.
02Steel & Erection
Engineering
Tendon geometry, anchorages and grouting are resolved on a single post-tensioning drawing.
03Steel & Erection
Post-Tensioning Works
Stressing is carried out in stages, with every step recorded. A tension report is issued at handover.
ABOUT THE SERVICE
Post-tensioning for
controlled spans and stiffness
Post-tensioning is an engineering method in which high-strength steel tendons in selected zones of a reinforced-concrete structure are stressed after the concrete has been cast, introducing a controlled compressive force into the structure. It can be used to achieve long spans, control tensile stresses in reinforced-concrete members and make more efficient use of cross-sections in certain structures.
The system can be used in a wide variety of structures, from bridges and slabs to water tanks and large reinforced-concrete silos. However, the tendon layout and stressing forces must always be determined by the structural design of each individual structure.
In silo projects, post-tensioning may be incorporated specifically to control hoop tension in large-diameter reinforced-concrete structures. The horizontal pressure exerted on the silo walls by the stored material makes the circumferential load-bearing system particularly important.
Rayf Teknik's slipform experience on tall reinforced-concrete structures helps establish the correct construction sequence on post-tensioned silo projects. As the silo shell is raised by slipform, the post-tensioning ducts, anchorage zones and other embedded items must be prepared in accordance with the design elevations.
Slipforming and post-tensioning are not the same process. The first is a method of constructing the reinforced-concrete structure; the second is a stressing technique used within the structural load-bearing system. The two can, however, be used together on the same silo project, which is why the site teams must work from shared construction drawings rather than independently of each other.
Once the concrete has reached the required strength, the tendons are stressed to the design values. Recording the stressing forces and inspecting the anchorage zones are key stages of the process. In bonded systems, the tendon ducts are also grouted as required by the design.
On post-tensioned silo projects, installing the tendon system details correctly as the slipform rises reduces the need for later modifications to the hardened concrete. All details relating to the stressing system must therefore be communicated to the site team before concreting.
Drawing on its experience in reinforced-concrete silos, slipforming and industrial structures, Rayf Teknik focuses on ensuring that, on projects incorporating post-tensioning, the construction method progresses in harmony with the other structural components. The aim is not merely to carry out the stressing operation, but to ensure that the structural behaviour envisaged in the design of the reinforced-concrete structure is achieved on site through correct construction details.
TECHNICAL SPECIFICATIONS
Post-tensioning technical specifications
Post-tensioning tendons, anchorages and stressing records are planned to suit the cross-section. Typical values are finalised through the site survey and structural analysis.
#
Specification
Value
01
Scope
Post-Tensioning Solutions
02
Category
Steel & Erection
03
Site
Tall structures and reinforced-concrete sections
04
Execution
Project-specific
05
OHS
In line with the site programme
06
Handover
With survey records and documentation
TECHNICAL ADVANTAGES
Why post-tensioning?
Post-tensioning increases spans, controls cracking and can allow slimmer sections. The benefits are assessed point by point.
RAYF
Continuous Concrete Placement
Continuous concrete placement with slipform prevents cold joints and creates a monolithic structure, providing a rigid, watertight and durable load-bearing system for silos and chimneys.
01
Continuous Concrete Placement
Continuous slipforming prevents cold joints and creates a monolithic, rigid structure.
SERVICE GALLERY
Post-tensioning project gallery
01 / 12
Post-tensioning engineering and detailing
OTHER SERVICES
Services offered alongside post-tensioning
View Details ↗
Bridge & Viaduct Piers
Bridge piers and viaducts
PierBridge
SlipformMethod
ViaductApplication
Geometry, verticality and load-bearing capacity are critical for bridge and viaduct piers and pylons. Tall wall-section pier shafts are raised using controlled formwork methods.
View Details ↗
Reinforced-Concrete Silos and Storage Structures
Konya Çimento / Topkapı Şişe Cam
10,000 tSilo
SlipformMethod
KonyaSite
Reinforced-concrete silos are designed to store large volumes of bulk materials. Product loads, the discharge system and process connections define the geometry of the shell.
View Details ↗
Silo Slipform Systems
Ilgın / Konya — cement plant
BİKİLTAŞClient
SlipformScope
KonyaSite
Silo slipforming allows tall reinforced-concrete silos to be built in one continuous pour. Concreting, reinforcement fixing and hydraulic lifting advance together in a single coordinated production cycle.
View Details ↗
Structural Steel
Seza Yapı — Seydişehir road construction site
Seza YapıClient
HangarFabrication & erection
SeydişehirSite
Structural steel delivers high load-bearing capacity for platforms, galleries and production buildings. It is also used to support equipment lines connected to reinforced-concrete structures.
POST-TENSIONING SUPPORT
Get support from
Rayf Teknik for your
post-tensioning projects.
We prepare site surveys and quotations for post-tensioning work on bridges, viaducts and silos.
Information & FAQ
Frequently asked questions about post-tensioning
Where post-tensioning is used, how stressing is recorded and how anchorages are protected.
What services does Rayf Teknik provide?
Rayf Teknik provides engineering, manufacturing and on-site installation services for slipform systems, reinforced concrete silos, industrial chimneys, structural steel and custom formwork systems.
Our work includes raw meal, cement, clinker, grain and lime silos; bridge and viaduct piers; wastewater treatment structures; minarets and domes; overhead and gantry cranes; and project-specific industrial applications.
We select the system, equipment and execution method according to each project's geometry, programme and site conditions. You can review completed work on our Projects page.
What is a slipform system and how does it work?
Slipform is a continuously moving formwork method used for tall reinforced-concrete structures such as silos, industrial chimneys, towers, and bridge or viaduct piers.
Hydraulic lifting equipment raises the formwork at a controlled rate while reinforcement work and concrete placement continue according to the construction programme. Continuous placement significantly reduces the risk of cold joints and creates a monolithic concrete structure.
Slipform is not limited to circular structures. Project-specific engineering allows it to be used for square, rectangular, polygonal, prismatic and other custom geometries.
What is the difference between slipform and climbing formwork?
Both systems are used for tall reinforced-concrete structures, but they progress differently.
Slipform rises continuously using hydraulic equipment, allowing concrete placement to proceed without interruption. This provides a major programme advantage for silos, chimneys, towers and similar structures.
Climbing formwork advances in stages. After each concrete lift reaches the required strength, the formwork is moved to the next level and reinstalled. The correct method depends on the structure's geometry, concrete design, programme and site requirements.
What are the advantages of a slipform system?
Slipform enables tall reinforced-concrete structures to be built quickly and under controlled conditions. Because the formwork rises without being dismantled and rebuilt at every level, it can provide a significant time advantage on large industrial projects.
Continuous concrete placement reduces cold-joint risk and helps create a monolithic structure. Other advantages include high production rates, less repetitive formwork labour, adaptability to different geometries and efficient work at height.
Where technically suitable, equipment can be modified for later projects. We can also provide supervision for clients who purchase a system and carry out the site application with their own team.
Where are slipform systems used?
Slipform can be used wherever height, repetitive geometry and continuous concrete walls are central to the design. Typical applications include:
- Cement and clinker silos
- Raw meal and raw-material silos
- Grain, feed, lime and aggregate silos
- Industrial chimneys
- Bridge and viaduct piers
- Control and communication towers
- Wastewater treatment and digester structures
- Dams, water-intake structures, mines and energy facilities
Systems can be engineered for cylindrical, square, rectangular, polygonal and other project-specific geometries.