As a result of comprehensive research and development carried out by Geoquest, TechSpan was launched in 1989.
This optimal solution provides builders with a state-of-the-art three hinge segmental precast concrete arch system for building short to medium span earth-overfilled bridging structures.
Engineering complexity in structural optimization
Precast concrete elements meeting strict geometric and material specifications
Installation under operational constraints
Applications
- Roadway and railway bridge underpass, overpass and covered tunnels
- Explosives and munitions storage facilities for military and industry
- Industrial reclaim conveyor tunnels and escape routes
- Commercial and pedestrian overfilled passages
- Rockfall protection sheds and galleries
- Pedestrian passage and animal crossings
Optimized manufacturing processes
Using our unique flexible concrete precasting formwork and quality-controlled casting process results in finished elements that conform to any and all geometric and material quality specifications.
Our design and material supply package often includes materials required to construct the necessary retaining structures for wing walls and spandrels, and also other precast solutions including footings, copings, barriers and slip joints.
Optimized installation procedures
Requiring only a narrow footprint to build, TechSpan installation is simple, rapid and predictable requiring only a small work crew, light tools and conventional equipment. Erection rates of 10 to 20 linear meters of arch per shift are easily possible with only a single crane with operator, while the use of two cranes with operator will speed production at the initial start of installation.
The TechSpan solution eliminates the need for intensive onsite formwork, scaffolding, joints or bearings. Installation over active roadways, railways, waterways and conveyance systems is possible without disruption to the ongoing activity.
The abbreviated installation procedure consists of the following steps:
- Establishing keyway foundations
- Receiving and arranging arch segments
- Segment placement by crane(s)
- Grouting of segments into the keyway
- Pouring of a crown beam or stitch joint
- Applying joint cover or waterproofing
- Backfilling per approved guidelines and specifications
Our solution allows:
Durability
The inherent durability of quality precast concrete provides a long service life with minimal maintenance requirements.
Cost savings
As opposed to alternatives, the cost savings using TechSpan increase as the fill height imposed on the arches increases.
Solution bundling
Designs and materials for headwalls, wing walls and collars are conveniently included in the Geoquest material supply package.
Full scope of services
A full scope of services, from inception to completion:
– Feasibility studies and estimates
– P.E. sealed designs and calculations
– Manufacturing and delivery of materials
– Onsite technical assistance
– Instrumentation and monitorization
Our solutions suit severall applications to: RetainCrossProtectStrengthen
