Almost 14 meters in one fell swoop

How Hächler AG pours high walls faster and more cheaply

The construction company Hächler AG did an excellent job during this project and, based on past experience, relied on the high performance guaranteed by the Mammut XT wall formwork system. The formwork with the integrated XT tie holes – to simply choose between three tying options – allows a maximum fresh-concrete pressure of 100 KN/m² and thus ensures rapid pouring processes with large filling volumes.

Faster with contractor-specific variant

The invitation to tender originally stipulated the use of climbing formwork with cycle heights of approx. 4 m for the construction of the walls. However, for the construction of the freestanding, 55 cm thick walls, Hächler AG’s department for building construction and civil engineering drew up a contractor-specific variant – with an initial pouring height of 13.80 m followed by two further cycles each with a height of 4.05 m. A decision that was intended to profit all participants.

The pouring of each 13.80 m cycle required 75 m³ of concrete. This quantity was poured in three stages: The first pouring stage was performed at six in the morning. Having waited for the concrete to harden, the second stage was performed at 11 a.m. and the third at 2 p.m.

To avoid overloading the formwork and the tie rods, the experienced Hachler team optimised the concrete recipe together with the supplier to enable the concrete to set faster. This massively accelerated the processes and ensured that the required eight-month construction period was adhered to.

The formwork was tied from one side using the XT taper tie 23, which also simplified and accelerated the work. Furthermore, the costs for the principal were reduced, as the bespoke solution resulted in fewer reinforcement joints and position surcharges.

Quick and safe with foldable working platforms

With the two additional 4.05 m climbing cycles, the target height of 21.90 m was reached. The KAB foldable working platform provided valuable assistance here in order to meet the stringent Swiss safety requirements with a minimum of installation work. The KAB can be taken quickly and directly from the stack and used as a working and safety scaffold. When folded, it enables space-saving storage and efficient transport. KAB consists of prefabricated folding platforms, planking and folding guardrailing.

The building shell was constructed on schedule and the walls shine forth in excellent quality. “We are proud of the result”, says Dario Scimonetti, head of building construction and civil engineering at Hächler AG, about the successful execution of this project.

MEVA systems:

• Mammut XT wall formwork
• KAB foldable working platform
• Triplex heavy-duty prop

Project:
New construction of a PET sorting plant, Unterengstringen, Switzerland

Contractor:
Hächler AG Hoch- und Tiefbau, Wettingen, Switzerland

Engineering and support:
MEVA Schalungs-Systeme AG Seon, Switzerland