Precast concrete parts
Application areas: new constructions and basic renovation
Precast concrete parts have various benefits: high quality due to prefabricated manufacturing, possible multifunctionality and they can largely be installed irrespective of the weather.
Shortening construction times and increasing the durability of road pavements are paramount to guaranteeing the availability and durability of road infrastructure in the long term. Precast concrete elements demonstrate substantial benefits in this respect, such as high quality due to prefabricated manufacturing and possible multifunctionality (for example by integrating sewer manholes or lighting systems). Furthermore, compared to conventional concrete or asphalt methods, they can largely be installed irrespective of the weather.
The use of precast concrete parts for structural maintenance has been investigated in the past years in previous research projects. Based on the positive experiences achieved thus far in this field of application, the aim was to exploit the benefits of the technology and to adapt and further develop precast systems for new constructions and basic renovations. In this context, new coupling and connecting elements between the individual precast units were developed and tested, as well as height adjustment systems that are independent of existing possibilities. In addition to checking technical and practical feasibility, the design of relevant road surfaces with a dense and porous concrete texture was to be investigated in particular.
A further focus of the research project is the investigation and illustration of the novel height adjustment and coupling systems in finite element models - here for multi-line and possibly multi-column precast systems. These are furthermore to be iteratively developed and calibrated on the basis of measurement and material parameters determined by a monitoring on the demonstrator. A comparison of different types of pavements is additionally was planned: precast units on a gravel and on an asphalt base layer. In addition to comparative investigations of the load-bearing behaviour, this was also carried out with the aim of reducing the necessary amount of underfill material to a minimum.
The construction of a demonstrator with twelve precast elements was successfully completed in November 2017.
The investigation of the lateral force transmission of the different coupling systems is carried out by a defined mechanical stress by means of simulation of wheel rollovers (MLS30) in the joint area, the metrological determination of the load capacity development with the FWD-Falling Weight Deflectometer. These are planned up to and including 2019.
The main purpose of the demonstrator on the duraBASt site is to investigate the practical feasibility and to conduct an initial evaluation of the durability of precast systems with newly developed height adjustment and coupling systems for new constructions and basic renovations. It also represents the essential component of the scientific research, for example calibration of the FEM models and for putting the new technology into practice.