Rehabilitation of access road and courtyard on an historical place with improvement of soil bearing capacity

Rehabilitation of access road and courtyard on an historical place with improvement of soil bearing capacity

Wawel Royal Castle, Cracow (Poland) | MDB Texinov

Project:

The Wawel Hill is a Jurassic limestone rock rising on the bank of Vistula river in Cracow city. It was occupied since the Paleolithic age and it has become the Royal residence of Polish rulers from the 11th century until World War II. The impressive Renaissance building, with its arcaded courtyard, is nowadays one of Poland’s most famous places for history and culture, hosting the Wawel Royal Castle Museum – State Art Collection.

The access road and the courtyard needed important renovation works, including the replacement of the outward boulder pavement, and the improvement of the subsoil bearing parameters

 

Specifications:

The subsoil of the yard consisted of an anthropological layer aged during many centuries, which main component was clay mixed with rubble. The base of the construction, old roof beams of caves, remainder of brick walls and empty spaces were found.

 

Wawel Royal Castle, Cracow (Poland) | MDB Texinov

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Engineering solution:

The designer aimed for the orthotropic reinforcement solution proposing a geosynthetic layer combined with filling material.

The new designed pavement was reinforced with a GEOTER FPET 150/150 geocomposite, with filling soil made of crushed gravel. The upper layer constitutes of sandstone pave plates, placed on blinding concrete.

Solution: High tenacity geocomposite with orthotropic tensile strength 150 kN/m in each direction : GEOTER® FPET 150/150

Conclusion: the bearing capacity has been tested in different places of the courtyard and access road.

The construction enabled the improvement of bearing capacity: the deformation modulus of the pavement raised from an initial value of 30 MPa up to 120 MPa with the geocomposite. This means an improvement factor of 4, and guarantees a long lifetime to the renovation. The geocomposite solution enabled the use of in-situ materials instead of new materials and therefore generated important costs savings.