XV Danube - European Conference on Geotechnical Engineering (DECGE 2014) H. Brandl & D. Adam (eds.) 9-11 September 2014, Vienna, Austria Paper No. 175 Abstract. The paper presents the monitoring program and field measurements of a deep excavation from Bucharest supported by anchored diaphragm walls. Comparisons are made between the measured deformations and the ones estimated in the design for the walls and the foundation ground. The experimental values resulted from the measurements from the inclinometer instruments mounted in the diaphragm walls, extensometers installed in the ground, as well as from topographical measurements of the vertical displacements of the diaphragm walls and the neighboring buildings. The monitoring stages were related to the execution stages of the excavation. For proper reading of the influence of the excavation on the neighboring buildings, the monitoring program also comprised mapping and measuring the evolution of their cracks and measurements of the underground water level outside de diaphragm walls precinct. Keywords: Deep excavation; Monitoring; Inclinometer; Extensometer; Ground anchors 1 INTRODUCTION 1.1 Designed building description On a site in N-E of Bucharest a development of office buildings is under construction in Bucharest, having 3B + GF + 11(12) F with a total built area of circa 90 000 m 2 , whereof circa 30 000 m 2 below the ground level. The basement occupies almost the entire property, while the three structures above the ground occupy about 60% of the site (according to authorized urban indices). At the date of drawing up this paper, the basements structure of the first two buildings and the entire structure of the first building were completed, while the third building (including the excavation) was going to start at a later time. 1.2 Brief description of the deep excavation stages The natural ground level is about +89.00 m ASL, while the final level of excavation is +77.10 m ASL. and +77.90 m ASL respectively, meaning circa 11-12 m depth. The hydrostatic level was indicated in Geotechnical Report between +77.00 ... +79.00 m ASL. For performing the excavation works from a working platform at +86.00 m ASL, a diaphragm wall of 60 cm thickness and 18 m length was realized through the slurry wall technology. The slope for performing the working platform (almost vertical in some areas) was retained by Berlinese wall or stabilized by shotcrete. After performing a feasibility study, the optimum solution for temporary support was by prestressed ground anchors of 20 m length and 20° drill angle disposed on a single level at +82.20 m ASL. Monitoring of a deep excavation from Bucharest sustained by anchored diaphragm walls A. Ene 1 , D. Marcu 1 , H. Popa 2 1 SC Popp & Associates Geotechnical Engineering SRL, Bucharest, Romania 2 Technical University of Civil Engineering, Geotechnical and Foundations Department, Bucharest, Romania