conversations.from: human
conversations.value: What could be a title for a book about P>"This, University, Italy</P with the genre: Engineering & Transportation, Engineering?
conversations.from: assistant
conversations.value: A title for this book could be 'Tall Building Foundation Design'
conversations.from: human
conversations.value: Provide the first four paragraphs for this book.
conversations.from: assistant
conversations.value: Tall Building Foundation Design
  The most effective means of carrying out a Category 3 analysis is to employ a pile group analysis program that considers non-linear pile–soil response and pile–soil–pile interaction, and is capable of handling all six components of loading simultaneously (e.g. the commercially available programs REPUTE or GROUP8). In employing such programs, the following procedure can be used:
  In carrying out the analyses described above, there are a number of computational issues that need to be considered when calculating the loads and moments in the piles and raft, as set out below.
  In principle, the following values of soil Young's modulus should be employed in the Category 3 pile group analyses:
  It has been found that the computed pile head loads and moments are not particularly sensitive to the soil modulus values used. As an example, the case of a pile group with a square array of 16 piles in a 4 × 4 configuration was analysed. Each pile was 45 m long and 2.5 m in diameter, and the centre-to-centre spacing between the piles was 8 m. For the ground profile considered, similar to that encountered at the site of the Incheon 151 Tower (see Chapter 15), each pile had an ultimate axial capacity of 49 MN. The following (factored) load combination was applied:
conversations.from: human
conversations.value: Provide five more paragraphs.
conversations.from: assistant
conversations.value: The effectiveness of each of these measures can be accessed via suitable analyses, which may often fall into Category 3 because of the complexity of the problem.
  The groundwater level can be controlled by dewatering, which involves some form of pumping to locally lower groundwater levels in the vicinity of the excavation. If it is possible, hydraulically isolating the internal part of the excavation from the outside is to be preferred, as it can reduce or even avoid unwanted drawdown, and possible consequent settlement, outside the excavation. Such isolation may be possible by either extending the wall down to a relatively impermeable layer, or else grouting the ground beneath, and in the vicinity of, the excavation to reduce its permeability. Grouting may impede or stop the penetration of water in subsoil with high permeability, such as in fissured and jointed rock strata. Rows of holes are bored on the soil, and grout, usually cementitious, is injected under high pressure. The cement grout will penetrate into the voids of the subsoil and form a relatively impermeable curtain vertically separating the ground water. Sometimes chemical grout (often silica-based) can be used; this creates a gel which can increase strength and reduce the permeability of the soil.
  If there is a need to lower the water table significantly within the excavation, and grouting or other methods are not feasible, it may be necessary to use recharge wells outside the excavation to reduce the risk of causing additional settlements and distortions of adjacent structures. Further details related to groundwater control are provided in several sources, including CIRIA (2000); UFC (2004); Puller (2003) and Powers et al. (2007).
  The simplest form of dewatering is sump pumping, where groundwater is allowed to enter the excavation where it is then collected in a sump and pumped away by robust solids handling pumps. Sump pumping can be effective in many circumstances, but seepage into the excavation can create the risk of instability and other construction problems.
  To prevent significant groundwater seepage into the excavation and to ensure stability of excavation side slopes and base it may be necessary to lower groundwater levels in advance of excavation. Available methods include
conversations.from: human
conversations.value: Delete the last sentence.
conversations.from: assistant
conversations.value: The effectiveness of each of these measures can be accessed via suitable analyses, which may often fall into Category 3 because of the complexity of the problem.
  The groundwater level can be controlled by dewatering, which involves some form of pumping to locally lower groundwater levels in the vicinity of the excavation. If it is possible, hydraulically isolating the internal part of the excavation from the outside is to be preferred, as it can reduce or even avoid unwanted drawdown, and possible consequent settlement, outside the excavation. Such isolation may be possible by either extending the wall down to a relatively impermeable layer, or else grouting the ground beneath, and in the vicinity of, the excavation to reduce its permeability. Grouting may impede or stop the penetration of water in subsoil with high permeability, such as in fissured and jointed rock strata. Rows of holes are bored on the soil, and grout, usually cementitious, is injected under high pressure. The cement grout will penetrate into the voids of the subsoil and form a relatively impermeable curtain vertically separating the ground water. Sometimes chemical grout (often silica-based) can be used; this creates a gel which can increase strength and reduce the permeability of the soil.
  If there is a need to lower the water table significantly within the excavation, and grouting or other methods are not feasible, it may be necessary to use recharge wells outside the excavation to reduce the risk of causing additional settlements and distortions of adjacent structures. Further details related to groundwater control are provided in several sources, including CIRIA (2000); UFC (2004); Puller (2003) and Powers et al. (2007).
  The simplest form of dewatering is sump pumping, where groundwater is allowed to enter the excavation where it is then collected in a sump and pumped away by robust solids handling pumps. Sump pumping can be effective in many circumstances, but seepage into the excavation can create the risk of instability and other construction problems.
  To prevent significant groundwater seepage into the excavation and to ensure stability of excavation side slopes and base it may be necessary to lower groundwater levels in advance of excavation.
conversations.from: human
conversations.value: Provide the last four paragraphs.
conversations.from: assistant
conversations.value: Limit state design, ; see also Axial capacity; Durability; Negative skin friction; Pile group and piled raft capacity; Structural design aspects; Ultimate capacity
  Pile load testing, ; see also Dynamic load test; Osterberg cell test; Pile integrity tests; Pile load test instrumentation; Static vertical load test; Statnamic test
  Seismic events, ; see also Category 3 analysis methods; Earthquake effects; Ground condition assessment; Liquefaction effects, mitigation of; Liquefaction potential assessment; Seismic hazard estimation; Structural response spectra
  Serviceability limit state loadings, ; see also Category 3 analysis methods; Group effects; Lateral pile response estimation; Pile group settlements; Pile spring stiffness value assessment; Piled raft settlement; Settlement estimation; Shallow foundation and raft settlement; Single pile foundation settlement