doi:10.3850/key-Ped-ISGI09

ABSTRACT

The existent Marina breakwaters in Lisbon with 12 m high were designed to sustain the interior variations water level. Due a change of the operation system there was a need to assure the safety conditions of the breakwaters for the variation of both interior and exterior water level. So the need for rehabilitation and reinforcement of the existent breakwaters and the quay wall with 264 m long and 27 m wide became inevitable. In this paper the design defined by PROMAN office and the alternative design proposed by JETSJ/Somague contractor related the rehabilitation and reinforcement of Marina breakwaters will be addressed. The geotechnical characteristics of the alluvia material, as well the design parameters, will be described. The design requirements related the static and seismic analysis of the Marina breakwaters will be presented. Particularly attention and focus of the design of the inclined micropiles with 127 mm of diameter and jet grounting columns with 1.2m of diameter proposed by the Contractor will be given. The constructions issues defined in the Technical Specifications will be addressed. The tests performed in micropiles to assess the design assumptions will be described. The instrumentation plan is referred.

Keywords: Rehabilitation; Reinforcement; Breakwaters; Quay wall; Jet-grouting; Micropiles.

© 2010 by Geotechnical Society of Singapore (GeoSS)