Optimization of Pile Groups: A practical study using Genetic Algorithm and Direct Search with four different objective functions
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Piling is expensive but often necessary when building large structures, for example bridges. Some pile types, such as steel core piles, are very costly and it is therefore of great interest to keep the number piles in a pile group to a minimum. This thesis deals with optimization of pile groups with respect to placement, batter and angle of rotation in order to minimize the number of piles. A program has been developed, where two optimization algorithms named Genetic Algorithm and Direct Search, and four objective functions have been used. These have been tested and compared to find the most suitable for pile group optimization. Three real cases, two bridge supports and one culvert, have been studied, using the program. It has been difficult to draw any clear conclusions since the results have been ambiguous. This is probably because only three cases have been tested and the results are very problemdependent.The outcome depends, for example, on the starting guess and settings for the optimization. However, the results show that the Genetic Algorithm is somewhat more robust in its ability to remove piles than Direct Search and is therefore to prefer in pile group optimization.
Place, publisher, year, edition, pages
2014. , 105 p.
TRITA-BKN-Examensarbete, ISSN 1103-4297 ; 409
Pile Group Optimization, objective function, Genetic Algorithm, Direct Search, Pattern Search
Pålgruppsoptimering, målfunktioner, Genetic Algorithm, Direct Search, Pattern Search
IdentifiersURN: urn:nbn:se:kth:diva-146832OAI: oai:DiVA.org:kth-146832DiVA: diva2:725554
Subject / course
Structural Design and Bridges
Master of Science in Engineering - Urban Management
2014-06-02, ELU Konsult AB, Valhallavägen 117, Stockholm, 13:30 (Swedish)
Svedholm, Christoffer, Licentiat
Pacoste, Costin, Docent