Excavation sequence

Excavation Sequence. Excavation commenced with scraping of exposed Lagoon slopes above the sludge level to a depth of six inches. This material was considered potentially contaminated and added to the Lagoon. After the slopes were scraped, benching of adjacent non-dioxin, solvent-contaminated soil was performed by the front loader. This material was transported by clamshell and placed on the staging pad. 

The TBM excavation process was modelled by a decrease of the effective force and pore pressure on the wall of the tunnel. This decrease depends on the time and the distance to the front of the excavation. The excavation was simulated according the excavation sequence shown in Figure 1 for an initial effective stress of Oh = Oh = 29.4 MPa (horizontal maximum and minimum compressive), and Ov = 7.14 MPa (vertical). 

Kim, Y.I., Amadei, B. Pan, E. 1999. Modeling the effect of water, excavation sequence and rock reinforcement with discontinuous deformation analysis. Int J Rock Mech Min Sci 36 pp.949-970. 

Fig. 9. Penstock excavation sequence, stages 1-7 and Promec jumbo layout...

The site is a carwash facility located in the city of Escondido, in southern California. A sequence of investigative and remedial activities has been performed since 1987 that established the presence, nature, and extent of subsurface hydrocarbons derived from former USTs. Since conducting these activities, the former USTs have been removed and the hydrocarbon-affected soil surrounding the USTs has been excavated. Additionally, all potentially recoverable LNAPL (i.e., gasoline) has been removed, leaving only residual hydrocarbon saturation (i.e., smear zone) in place at the water table. Subsequent pump-and-treat activities have reduced dissolved BTEX concentrations to asymptotic levels (Figure 13.9). 

According to the vendor, the estimated price of remediation using a soil slurry-sequencing batch reactor system was 50 to 110/m of waste treated in 1995. Costs are usually 1.5 to 2 times less than excavation and inceration. The quantity of waste and initial contaminant concentration were cited as the most significant factors effecting price (D10036N, p. 15 D15328G, p. 7). 

The problem of the correct sequence of excavated Peruvian textiles is a complex one. Until we have an accepted seriation, it will be difficult to draw any conclusions regarding the temporal distribution of dyes in any area. 

Table I presents the mean chemical composition of the lake for the major ions. In this paper only the sulfate ion will be considered. The Mt. Mesly sequence contains the southernmost occurrence of the Bartonian gypsum beds, formerly excavated for plaster manufacturing. Dissolution of gypsum considerably enhances the sulfate concentration of waters in the northern part of the alluvial Cr6teil plain. Mean samples were taken from piezometers which are shown in Fig. 1 A—G, L and 201). It was possible to sample separately surface and bottom water from piezometer 201 (201 s and 201 ) as well as from piezometer L (surface Ls, bottom and medium height ).

Major objectives of the Aspo Pillar Stability Experiment are to demonstrate the capability to predict spalling in a fractured rock mass and to investigate the effect of the backfill (confining pressure) on the rock mass response. The FRACOD modelling aims to predict properly the fracturing process and the development of AE events during the planned sequences of excavation-confinement-heating. 

Due to contamination problems, most aDNA researchers will not use curated human skeletal material for analysis, but will only work on currently or recently excavated material. Preferably, bones will be excavated by people whose DNA sequences are known, either someone from the DNA laboratory or by a designated excavator. 

Some of the worst conditions are met in excavations that have to be taken below the water table (Forth, 2004). In such cases, the water level must be lowered by some method of dewatering. The method adopted depends on the permeability of the ground and its variation within the stratal sequence, the depth of base level below the water table and the piezometric conditions in underlying horizons. Pumping from sumps within an excavation, bored wells or wellpoints are the dewatering methods most frequently used (Bell and Cashman, 1986). Impermeable barriers such as steel sheet piles, secant piles, diaphragm walls, frozen walls and grouted walls can be used to keep water out of excavations (Bell and Mitchell, 1986). Ideally, these structures should be keyed into an impermeable horizon beneath the excavation. 

The area of woodlands cleared. Efficient use of the landfill area should be maximized. The amount of initial excavation will be minimized because, while one cell is being filled with waste, the next cell in sequence is being partially excavated. When the current working portion is completed, the liner system should be extended over the newly excavated cells. Once the new cells become the active cells, the cap system will be extended over the completed cells. 

The drilling results suggest the depth to bedrock to be about 4.8 21.5 m with an upslope increase in the overburden thickness. Bed rock encountered is mainly shale and sandstone. The 126 m excavated length of the Adit-2 reveals interbedded sequence of dark grey, micaceous sandstone and carbonaceous shale with occasional coal (shaly) beds. 

Based on the above analysis, a circular shape vertical shaft does not need extra supports in most conditions such as struts or tie-back anchors. Excavation can be done quickly without complicated construction sequence or coordination between the excavator and support installer. There are many cases using the circular shape worldwide, including... 

Ammerman, A. J. Polglase, C. R. In Arene Candide A Functional and Environmental Assessment of the Holocene Sequence (Excavations Bemabo Brea-Cardini 1940-50) Maggi, R., Ed. II Calamo Rome, Italy, 1997 pp 573-592. 

First reclaim land and subsequently construct the civil structures in the dry after which any excess fill material is excavated. A significant advantage of this sequence is that the civil works can be executed from land which may be very... 

After initial mine development work, a phase of slope excavation and preparation is undertaken to prepare the orebody for full extraction. Tbe sequence of operations that follows involves breaking up the ore material (by drilling and blasting), removal of the ore and its transportation to a concentrator (haulage). Haulage includes hoisting operations and conveyor, rail or truck transportation. 

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