The North Ring Road of Lamongan Project Section I, which stretches from Sta. 0+000 to Sta. 3+265, is indicated to be built on soft silt soil. This paper discusses the effect of Prefabricated Vertical Drains (PVDs) length on the amount of settlement that occurs in soft soil. The method used was to compare the installation of PVDs at a quarter, half and three quarters of the thickness of the compressible soil layer. The varying lengths of PVDs were modeled on PLAXIS2D software. The results show that the longer PVDs are installed in the compressible soil, the greater settlement occurs.

Akan & Sert. 2021. “Investigation of the Consolidation Behaviour of Soft Soil Improved with Vertical Drains by Finite Element Method”. International Journal of Engineering & Applied Sciences (IJEAS). Vol.13, Issue 3 (2021) 93-105.

Al-Adhah, Kadhim & Naeem. 2019. “Reviewing the Most Suitable Soil Improvement Technique for Treating Soft Clay Soil”. Ahmed Raad Al-Adhadh Journal of Engineering Research and Application. ISSN:2248-9622 Vol. 9, Issue 8 (Series-V) Aug 2019, pp 01-11.

Fitriansyah, Anggarini, Muzaidi, Frandika & Sabrina. 2024. “Analisis Pengaruh Konfigurasi Prefabricated Vertical Drain (PVD) terhadap Waktu Konsolidasi dan Penurunan Tanah (Studi Tanah Lempung Lunak Banjarmasin)”. Agregat, Vol.9, No.2, November 2024.

Gulhane, Chaundhary, Kolte & Turukmane. Prefabrication Vertical Drain for Soft Soil Consolidation.

Hayati, Roesyanto & Iskandar. 2020. “Analisis Efek Smear Zone Akibat Pemasangan PVD terhadap Proses Konsolidasi Timbunan dengan PLAXIS 2D dan 3D”. Media Komunikasi Teknik Sipil. Volume 26, No.2, 2020, 140-149.

Jiang, Lu, Chen, Dai, Gao & Li. 2020. “Research Progress of Soft Soil Foundation Treatment Technology”. IOP Publishing. The 6th International Conference on Environmental Science and Civil Engineering. doi:10.1088/1755-1315/455/1/012081.

Lubis, Roesyanto & Hasibuan. 2023. “Analisis Pengaruh Preloading Kombinasi Prefabricated Vertical Drain pada Proses Konsolidasi di Proyek Reklamasi di Samping Tangki CPO antar Pulau Belawan Berdasarkan Bore Log BH-2. Syntax Admiration”. Vol.4, No.8, Agustus 2023.

Mariyana, Zaika & Harimurti. 2021. “The Effect of The Use Prefabricated Vertical Drain (PVD) on Soft Soil Construction of Bandung City Road with Finite Element Analysis”. Rekayasa Sipil. Volume 15, No.3 – 2021 ISSN 1978-5658.

Mohammad & Sharma. 2020. “An Experimental Study and Design of Vertical Drains for Ground Improvement”. International Journal for Technological Research in Engineering. Volume 7, Issue 5, January-2020.

Mochtar, I.B. 2012. Empirical Parameters for Soft Soil in Situ. Jurusan Teknik Sipil, ITS. Surabaya.

Najih & Hariyanto. 2020. “Studi Hidrokimia Air Tanah Dangkal di Kecamatan Deket Kabupaten Lamongan”. Swara Bhumi. Volume V Nomor 9 Tahun 2020, Halaman 83-89.

Reang, Pal & Paul. 2020. “Importance of Vertically of PVD in Consolidation Settlement of Prefabricated Drain-Improved Soft Soils”. Proceeding of Indian Geotechnical Conference 2020. Andhra University.

Widoanindyawaty, Wardani and Partono. 2016. Analisa Efektifitas Kedalaman Pemasangan PVD Studi Kasus Konstruksi Timbunan Apron Bandara Ahmad Yani Semarang.