Staged construction

1 Optimizing the slope geometry by using counterweight berms 

This technique has already been discussed in section 6.4. The construction is realised in small lifts with allowance for some consolidation time in between. The effect of (partial) consolidation is taken into account in order to define the increase in shear strength of the soft subsoil. 

Drainage of the subsoil to reduce waiting times in between subsequent fill lifts, and thus minimising the construction period, is a commonly used construction method. Dissipation of the excess pore pressures can be achieved by the installation of vertical drains. In addition, vacuum pressure can be apphed to the system. The vacuum pressure also acts as an additional preload. 

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The phenanthroindolizidine alkaloid (-)-antofine (95) exhibits high cytotoxicity to drug-sensitive and multidrug-resistant cancer cells by arresting the G2/M phase of the cell cycle. In the first asymmetric total synthesis of (-)-95, the late-stage construction of pyrrolidine 94 for the final Pictet-Spengler cyclo-methylenation to 95 was performed by RCM and subsequent hydrogenation (Scheme 18) [67]. 

A Pfizer group described the first preparation of 148 that did not involve a late stage construction of the 4(5//)-oxazolone (Scheme 6.38). Instead, their strategy... 

The primary products are fed at the top of the extraction column. The composition of feed, extract, raffinate, and extractant is analysed in dependence on superficial velocity of the gaseous (continuous) phase. In two series of experiments either the phase ratio or the spraying density are kept constant. The stage construction is made by means of a computer program. 

After this stage construct a key to the taxa. If necessary, construct separate keys to flowering- and fruiting material, or to male and female specimens. 

Given this number of stages, construction of a similar McCabe-Thiele diagram for other components in the feed, such as impurities, allows the calculation of the extent to which these impurities extract into the organic phase. If two or more extractable components are each in sufficient concentration to affect the distribution coefficient of the other species, e.g., TBP extraction of U02(N03)j and HNOa, the equilibrium lines for the two components cannot be specified in advance but must be calculated by an iterative procedure, similar to that to be illustrated in Sec. 6.6 for the zirconium-hafnium separation. 

Pattenden and co-workers reported the total synthesis of 14,15-anhydro-pristinamycin 11b 1219. Retrosynthetically, the authors proposed a late-stage construction of the macrocyle via an sp -sp Stille couphng of the vinyl stannane 1220... 

An intramolecular Friedel-Crafts reaction of a diene and an electron-rich aromatic moiety, promoted by BF3-Ft20, was used in the late stage construction of cyclohexyl ring in an approach to the marine natural product pseudopterosin aglycone. In a somewhat related transformation, it has been demonstrated that aromatics can be converted into the corresponding diarylmethane derivative on exposure to a-methoxyacetic acid in the presence of trifluoroacetic anhydride (TFAA) and BF3-Ft20 (eq 49). ... 

Lactam 243 was thus proposed to be a versatile intermediate which could possibly permit entry to echitamine or akuammiline type scaffolds. No further work was described by this group toward these ends. This work, however, can be considered as the first late stage construction of the C6—C7 bond to form the indoline quaternary center of the akuammiline core. 

Some of the options available for selecting a steam turbine are as follows. These could be in single stage or multi stage construction. Further details can be dis-cussed/obtained from the vendors concerned to suit the specific requirements on site... 

Quality The completion acceptance stage Construction Health and epidemic prevention and occupational disease prevention and control of management and effect Safety check Hidden dangers rectification of Management improvement Civilization construction effect Safety accidents and bad social influence Design drawings and/or disclosure came... 

Planned stage construction is the construction where the asphalt layers are constructed at stages according to a predetermined time schedule. 

A key prerequisite for a planned stage construction is that all subsequent stages (usually one plus one) should be applied according to schedule and before pavement fatigue signs appear. 

The planned stage construction may be preferred in cases where the entire fund is not available for the construction of the full design thickness or there are difficulties in estimating traffic for a long design period (say 20 or 30 years). 

It should be highlighted that when planned stage construction is decided, regular traffic counts during the first period after construction to re-adjust, if needed, the time scheduled for the second stage of construction. 

The minimum performance period is the shortest amount of time an initial pavement structure, or stage construction, lasts before some intervention is performed. 

The maximum performance period is the maximum practical amount of time expected from a given pavement structure or stage construction. Theoretically, the maximum performance period should be equal to the analysis period, but in practice, this rarely happens (taking into consideration the effect of environmental factors, surface deterioration, etc.). 

The methodology recommends to cost the pavement structure determined and also to carry out an economic analysis among alternative pavements using different materials. Stage construction may also be selected. For more information, see AASHTO (1993). 

Finally, the method also provides a means for stage construction and recommendations for economic analysis. 

The methodology offers the capacity of pavement design in case of stage construction of the... 

The process for the determination of the layer thickness in case of stage construction is similar to the one proposed by Asphalt Institute (1999). A working example is given in... 

The historical construction data, for instance, year/month of construction, one stage or planned stage construction, maintenance/rehabilitation history, materials used, layer thickness, bearing capacity of formation layer material and anything else considered useful. 

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