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Georgios K. Bekasa, Georgios E. Stavroulakisb
a,b Department of Production Engineering and Management, Technical University of Crete, Greece
Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Outline
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Outline
Objectives Optimization scenarios Variables of the optimization problem Model
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Outline
Objective function Constraints Optimization methodology Conclusions
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Resources
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Resources
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Objectives
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Objectives
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Optimization scenarios
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Optimization scenarios
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Variables of the optimization problem
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Variables of the optimization problem
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Variables of the optimization problem
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model A multi-
storeyed building, located on Bahrain.
Plan view: Rectangular shaped, 30x35 m.
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model A depth equal to: 1.5B
+ Lp (where: B is the smaller dimension of the foundation and Lp is the length of piles) is used to estimate the depth, where the applied loads have a negligible effect (≈ 0.1q, where q is the applied load).
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model The efficiency
of the pile group is taken conservatively as equal to 1.
The soil layers are treated as one equivalent layer by following the method described by Bowles.
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model•The pressures below each column are calculated and compared with the ultimate bearing capacity of the soil. •The structural design of the raft is based on its division into 3 intermediate strips and 2 edge strips (that have half of the width of the intermediate strips).Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Model The adjusted elasticity method is used for
the estimation of the settlement caused by the raft assisted by a surrogate model for the calculation of the influence factor described in the formula.
The total settlement of the group of piles is calculated by the methodology proposed by Randolph and Worth.
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Objective function
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Objective functionTotal cost = Cost of raft forming +
Cost of the concrete and the steel reinforcement of the raft + Cost of the piles + Excavation costs related to the soil improvement layer + Filling costs related to the soil improvement layer + ∑pi
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Constraints
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Constraints
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Constraints
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Constraints
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Optimization methodology
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Optimization methodology Genetic
algorithms via the use of the optimization toolbox of Matlab.
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Conclusions
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Conclusions
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Conclusions Furthermore, for both scenarios, the optimal
number of piles for a typical row or a typical column of the pile group is closer to the lower limits than the upper limits.
A gradual relaxation of the limits of the variables can take place by accepting the solutions that appear with a higher frequency -as optimal solutions- and accordingly by excluding those that appear as not optimal.
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Georgios K. Bekasa, Georgios E. Stavroulakisb
a,b Department of Production Engineering and Management, Technical University of Crete, Greece
Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
Georgios K. Bekas and Georgios Stavroulakis - Cost optimization of a raft foundation including pile group design optimization and soil improvement considerations
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