Smart software as the basis for optimal floor element design

In Concrete & Steel Construction Issue 4 of 2018, the article "Versatile software for the precast concrete industry" explained how software specialist i-Theses offers a solution for the integral process from order to delivery of floor elements. In addition to the administrative part, the drawing work, production and installation on site, however, structural analysis is also of great importance.

Analysis of channel plates under the influence of penetrations and recesses.

According to the European Construction Products Regulation 305/2011, every construction product placed on the market must meet seven basic requirements. The basic principle reads, "the construction work as a whole, as well as its individual parts, must be fit for their intended use. The first two fundamental requirements relate to structural analysis:

1 Mechanical resistance and stability:

a. prevention of collapse;

b. limitation of significant distortion;

c. prevention of damage to the structure or other parts by significant deformation.

2 Fire Safety:

d. ensuring load carrying capacity during fire.

This makes it clear that the calculation is an integral part of the regulation, which forms the basis of a Declaration of Performance (DoP) and CE marking. The guide for structural calculations are harmonized standards of which the Eurocodes form the backbone. For precast concrete floor elements, specific product standards exist in addition to the general provisions (EN13369):

Channel plates EN 1168

Combination floors EN 15037

Ribbed floor elements EN 13224

Wide plates EN 13747

Total Solution
In 2006, Brecht Beirinckx of Ingenieursbureau Streng-th was asked to advise a new manufacturer on the calculation of pre-stressed channel plates. "This advice resulted in a calculation sheet that was well received and later evolved into a full-fledged stand-alone
application, PreConSlab, which was launched in 2010," Beirinckx looks back. "It soon became clear that PreConSlab and i-Theses' tools could be used complementarily. In 2011, i-Theses and Streng-th formed a partnership to offer a total solution for channel plates."

AutoFloor - prestressed floor elements are automatically calculated with PreConSlab.

Integration
The strength of this cooperation lies in the far-reaching integration of drawing and calculation. "The geometric characteristics of the floor element and the engaging loads are sent from the drawing directly to the calculation module and calculated through," Beirinckx continues. "The result with optimized reinforcement is incorporated into the drawing. Subsequently, a calculation report can be generated." PreConSlab also features a graphical user interface, with which detailed R&D calculations can be prepared and analyzed. Through thorough parameterization, almost any shape can be defined. It is also possible to modify calculation settings and norm coefficients that can be saved as a template.

Random loads on combination floor.

Continued
PreConSlab was initially developed for hollow core slabs (EN1168). Due to the growing demand for the integrated possibility of drawing and calculation of combined floors, the package evolved and the software was extended to include calculation rules for combined floors (EN15037). "With the introduction of the Eurocodes 2.0 - the new generation of building standards, foreseen for 2021-2023 - a next step forward will be made towards a thorough optimization and sustainable design of floor elements," said Beirinckx.

Review
The development of PreConSlab takes place within the corporate walls of Streng-th. This makes it possible to continuously test the available calculation rules against practical cases. Beirinckx: "By monitoring the evolution of the standards and the available literature, PreConSlab remains up-to-date. Thanks in part to the practical experience present within our office, the PreConSlab-AutoFloor tandem has become the reference within the industry."

Text | Streng-th/Chris Elbers   Image | i-Theses/Streng-th
Featured image: Bending resistance prestressed channel board with openings: M_Ed vs M_Rd .