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Explore current issues in the design and construction of micropile systems, focusing on European standards, field tests, case histories, and installation effects. Learn about CEN European standards, micropile design based on load tests, and stabilization techniques after installation.
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Tokyo IWM August 2004 PRESENT ISSUES IN DESIGN AND CONSTRUTION OF MICROPILE SYSTEMS Prof. Roger FRANK CERMES (ENPC-LCPC)
1) Present state of European Norms (design, construction and testing) 2) Need for well documented field tests and case histories 3) Control of installation effects
CEN/TC 250 Date: 2004-08 EN 1997-1 CEN/TC 250 Secretariat: NEN Eurocode 7 Geotechnical design - Part 1: General rules Eurocode 7 Entwurf, Berechnung und Bemessung in der Geotechnik – Teil 1: Allgemeine Regeln Eurocode 7 Calcul géotechnique - Partie 1: Règles générales ICS : 93.020; 91.080.01
Under preparation : Euronorm on pile load tests (from ETC3 work)
2) Micropile design from well documentedload tests and case histories
AXIAL LOAD ON VERTICAL PILE Force (kN) ( compression ) Depth z (m)
AXIAL LOAD ON INCLINED MICROPILE Force (kN) ( traction ) Depth z (m)
_______ Movement of the water level ( sea tide, river flow) _______ Wooden piles : B = 0,30 m s/B = 4 Micropiles : B = 0,22 m s/B = 10
STABILIZATION OF THE SETTLEMENTS AFTER MICROPILES INSTALLATION
RAILWAY EMBANKMENT STABILIZED BY MICROPILES : Additional settlement due to the installation of the micropiles