土方明挖英文施工方案construction method statement.docVIP

1. MAIN DAM FOUNDATION EXCAVATION OBJECTIVE The main objective of this method statement is to describe in detail the sequence of works and establish priorities of work to allow embankment filling to start by scheduled in the baseline programme on 17-Jan-2003. An immediate objective will be to expedite works and expose the plinth at the dam foundation for geotechnical investigation. This method statement and includes the following: Haul roads and disposal areas, Preparation of secondary river crossings, Dewatering, Preparation of loading platform, and Earth/rock excavation for integrated cofferdam foundation. ZONING OF WORK AREAS: From the drawing, ‘by drawing a line connecting the highest point of the ridges of both left and right banks, the main dam work area is divided into the following work zones: Area 1: From downstream face of auxiliary cofferdam to the dam axis of integrated cofferdam; Area 2: From the dam axis of integrated cofferdam to the main dam axis, below elevation 130m for the right bank, below elevation 140 for the left bank, and including the riverbed. Area: From the main dam axis to the down stream limit of Main Dam, below elevation 130m for the right bank, below elevation 140 for the left bank, and including the riverbed downstream of MD Axis. Area 4: From the dam axis of integrated cofferdam to downstream limit of the Main Dam, above elevation 130m for the right bank, above elevation 140 for the left bank. Each work zone is is further divided into sub-areas, each subdivision is basically defined into left abutment, riverbed and right abutment sections. Please refer to drawing no. MDEX-MS-001 (Attachment 1) METHODOLOGY Preparation of Haul Roads Disposal Areas Haul Roads The following haul roads shall be prepared for haulage of excavated material: Road R1: Main haul road Road R1-1: Connects right abutment at EL 210 to R1. Road R1-2: From loading platform at Right Abutment @EL 130, to the upstream face of auxiliary cofferdam, and connected