Sains Malaysiana 41(7)(2012): 847–854

Penggunaan Kaedah Pengoptimuman Kelompok Zarah dalam Menilai Keboleharapan Analisis Kestabilan Cerun Tanah

(Application of Particle Swarm Optimization in Evaluating the Reliability of Soil Slope Stability Analysis)

Mohd Raihan Taha*, Mohammad Khajehzadeh & Ahmed El-Shafie

Jabatan Kejuruteraan Awam dan Struktur, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia

Diserahkan: 25 April 2011 / Diterima: 13 Februari 2012

ABSTRAK

Objektif kajian ini adalah untuk menunjukkan pembangunan kaedah berangka untuk menilai keboleharapan cerun tanah dan menentukan kebarangkalian permukaan gelonsoran genting. Fungsi prestasi dirumuskan menggunakan kaedah had keseimbangan Bishop mudah untuk mengira indeks keboleharapan. Indeks keboleharapan yang ditakrifkan oleh Hasofer dan Lind digunakan sebagai indeks ukuran keselamatan. Pencarian permukaan gelonsoran genting secara kebarangkaliannya yang berkaitan dengan indeks keboleharapan terendah dirumuskan sebagai masalah pengoptimuman. Seterusnya pengoptimuman kelompok zarah digunakan untuk mengira indeks keboleharapan Hasofer dan Lind dan kebarangkalian permukaan kegagalan genting. Penggunaan algorithma ini ditunjukkan melalui tiga contoh berangka daripada kajian terdahulu. Keputusan menunjukkan bahawa kaedah yang dicadangkan berupaya untuk memberikan penyelesaian yang lebih baik bagi analisis keboleharapan cerun tanah berbanding dengan kaedah yang dilaporkan dalam kajian-kajian terdahulu.

Kata kunci: Keboleharapan cerun; kestabilan cerun; pengoptimuman kelompok zarah

ABSTRACT

The objective of this research was to show the development of a numerical procedure to evaluate the reliability of earth slope and locating the critical probabilistic slip surface. The performance function is formulated using simplified Bishop’s limit equilibrium method to calculate the reliability index. The reliability index defined by Hasofer and Lind was used as an index of safety measure. Searching the critical probabilistic surface that was associated with the lowest reliability index was be formulated as an optimization problem. In this paper, particle swarm optimization was applied to calculate the minimum Hasofer and Lind reliability index and critical probabilistic failure surface. To demonstrate the applicability and to investigate the effectiveness of the algorithm, three numerical examples from the literature were illustrated. Results showed that the proposed method was capable of achieving better solutions for reliability analysis of slope compared with those reported in the literatures.

Keywords: Particle swarm optimization; slope reliability evaluation; slope stability

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*Pengarang untuk surat-menyurat; email: drmrt@eng.ukm.my