caa a22 4500 467930414 CHVBK 20180406152941.0 cr unu---uuuuu 170328e20060201xx s 000 0 eng 10.1007/s10706-004-2104-4 doi (NATIONALLICENCE)springer-10.1007/s10706-004-2104-4 Construction Problems on the Karstified Limestone Tuffs of Condeixa, Central Portugal: A Case Study [Elektronische Daten] [M. Ferreira, J. Velho] During the excavations for the foundations of a three storey building on the limestone tuffs of Condeixa, Central Portugal, a large dissolution fissure and smaller dissolution voids were found. Since the area has never been the subject of engineering geology investigation, it was decided to evaluate the risk associated with the construction of the building. These limestone tuffs were formed in a continental environment by the precipitation of calcite carried by the water coming from the large limestone body in the east. The precipitated calcite mixed with the terrigenous materials and around trunks and leaves of plants, originating a very heterogeneous and porous ground, which is characteristic of limestone tuffs. The study started with a detailed geological survey followed by a large number of destructive drillings, located essentially under the pad foundations. The results revealed several karstic cavities with serious problems for the building foundations and the structure, and many smaller dissolution cavities, often filled with clayey soils. The ground treatment solutions used included, dental cleaning, filling with concrete or granular material the dissolution structures accessible at the level of the foundation, reinforcement of the footing and the structure of the building and adding a continuous foundation beam to hold the foundations together. The cost of the engineering geology study, site investigation, ground treatment, and the reinforcement of the foundation and building, increased the total construction cost from 2%, at the design stage, to 4.8%. Springer, 2006 construction problems nationallicence foundation treatment nationallicence karst nationallicence limestone tuffs nationallicence site investigation nationallicence Ferreira M. Department of Earth Sciences, University of Coimbra, Portugal aut Velho J. Department of Geosciences, University of Aveiro, Portugal aut Geotechnical & Geological Engineering Kluwer Academic Publishers 24/1(2006-02-01), 101-116 0960-3182 24:1<101 2006 24 10706 https://doi.org/10.1007/s10706-004-2104-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10706-004-2104-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ferreira M. Department of Earth Sciences, University of Coimbra, Portugal aut NATIONALLICENCE 700 1- Velho J. Department of Geosciences, University of Aveiro, Portugal aut NATIONALLICENCE 773 0- Geotechnical & Geological Engineering Kluwer Academic Publishers 24/1(2006-02-01), 101-116 0960-3182 24:1<101 2006 24 10706 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer