15 seconds to battery recharge
A brand new kind of trolleybus is cruising the city of Geneva. The electrically operated buses don’t require continuous power supplied by overhead lines: they recharge their batteries directly at bus stops in the blink of an eye.
How does it work? Each bus stop along the test route between Geneva’s airport and convention center is equipped with a charger that connects to the bus via a movable, laser-controlled arm. It takes a mere 15 seconds to recharge the bus batteries.
By recharging the electrically operated vehicles at the bus stops as quickly as possible, the project aims to:
- Eliminate the need for a continuous power supply
- Reduce infrastructure costs
Light, yet strong enough for structural capability
LafargeHolcim’s UHPC concrete was selected to meet a specific challenge of this project: light, thin-walled hollow concrete with the strength necessary for structural capability. After meeting the preliminary specifications, LafargeHolcim still had to address the following challenges:
- Achieving reliable results for the L-shaped prototype without air pockets
- Finishing at a formwork surface to create a smooth surface
- Casting the asymmetrical opening of the bus stop as one piece, with several reinforcements given the hydrostatic pressure of the 4.3-meter-high element
- Preventing shrinkage cracks, which could quickly fracture the thin parts and become dangerous
- Filling the interior cavity space of the vertical parts near the opening with a rigid foam. A solvent was used to dissolve the foam after the concrete was poured, which allowed it to be removed easily and the formwork of the entire bus stop to be stripped.