Slurry Improvement by Direct Drainage Vacuum Preloading Method

2015 ◽  
Vol 744-746 ◽  
pp. 589-592
Author(s):  
Y.Z. Bai ◽  
Jian Chen ◽  
Bei Cheng
Keyword(s):  
Soil Depth ◽  
Soil Surface ◽  
Vacuum Preloading ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Horizontal Drainage ◽  
Stabilized Soil ◽  
Drainage Effect ◽  
Preloading Method ◽  
Sand Cushion

Traditional vacuum preloading method has two drainage parts: 1) horizontal drainage part-sand cushion; 2) vertical drainage part-(Prefabricated vertical drain (PVD) and so on). During vacuum preloading process, the drainage effect of horizontal sand cushion is strong near stabilized soil surface and decreases rapidly at deeper position, while drainage range of vertical drain includes whole stabilized soil depth and its drainage ability is higher. So, it is important to improve the drainage design of vacuum preloading system to transmit vacuum head to vertical drain more efficiently. This paper presents a new vacuum preloading method-direct drainage vacuum preloading method (DDVP method). Compared with traditional vacuum preloading method, this system cancels horizontal drainage part-sand cushion and uses sealed pipe to directly connect with PVDs. Vacuum head can be transmitted into PVD without attenuation. Field test is applied to study the effect of slurry improvement of this method.

scholarly journals Design Method and Verification of Electroosmosis-Vacuum Preloading Method for Sand-Interlayered Soft Foundation

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Yunliang Cui ◽  
Jianbo Tu ◽  
Xinquan Wang ◽  
Hongguo Diao ◽  
Qianru Ge
Keyword(s):  
Design Method ◽  
Simulation Method ◽  
Electrical Circuit ◽  
Test Results ◽  
Vacuum Preloading ◽  
Foundation Treatment ◽  
Vertical Drain ◽  
Soft Foundation ◽  
Prefabricated Vertical Drain ◽  
Preloading Method

The design method of electroosmosis-vacuum preloading for soft foundation treatment is not systematic and complete, thereby restricting the application of the technology in engineering. A design method for the electroosmosis-vacuum preloading treatment of sand-interlayered soft foundation is therefore presented. A compressible electrical prefabricated vertical drain is developed, and a vacuum sealing and draining system is designed for the application of the electroosmosis-vacuum preloading in sand-interlayered soft foundation. Calculation formulas of site resistance considering the interlayer and interface resistivity of the electrode are established to design the power supply and electrical circuit. A simple numerical simulation method is proposed to predict the ground settlement treated by electroosmosis-vacuum preloading. A field test of electroosmosis-vacuum preloading is designed using the suggested method, and comparison tests between the electroosmosis-vacuum preloading and the vacuum preloading are performed to verify the proposed technique. The test results show that the proposed design method is reasonable for the design of electroosmosis-vacuum preloading in engineering.

scholarly journals APPLICATION OF SUPER BOARD DRAIN (SBD) TO REPLACE THE SAND MAT IN SOFT SOIL TREATMENT BY USING PREFABRICATED VERTICAL DRAIN (PVD) WITH PRELOADING METHOD

2009 ◽  
Vol 12 (18) ◽  
pp. 76-84
Author(s):  
Phan Vo ◽  
Giang Thien Nguyen
Keyword(s):  
New Technology ◽  
Soft Soil ◽  
Construction Project ◽  
Soil Treatment ◽  
Horizontal Drain ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Horizontal Drainage ◽  
Preloading Method ◽  
East West

The report will introduce a new technology using Prefabricated Horizontal Drain (called Super Board Drain -SBD) which is replaced for Sand Mat in soft soil treatment by using Prefabricated Vertical Drain (PVD) with preloading method and sand filled layer (Sand Mat) designed as the horizontal drainage for PVD through East-West Highway Construction Project.

Application of a Modified Vacuum Preloading Method on a Dredged Fill Soft Foundation

2012 ◽  
Vol 170-173 ◽  
pp. 3130-3134 ◽  
Author(s):  
Yun Liang Cui ◽  
Ming Jun Gao ◽  
Zhi Hao Liu
Keyword(s):  
Bearing Capacity ◽  
Reinforcement Effect ◽  
Large Area ◽  
Vacuum Preloading ◽  
Soft Foundation ◽  
Short Period ◽  
Dredging Sludge ◽  
Made In China ◽  
Preloading Method ◽  
Sand Cushion

A lot of large area lands were made in China coastal areas by dredging sludge from the sea. The dredged fill ground had a very low bearing capacity which should be increased as soon as possible to meet the requirements of constructions. However, conventional vacuum preloading could not be used for this purpose because the sand cushion could not be laid on the sludge ground due to the very low bearing capacity. To solve this problem, a modified vacuum preloading method without sand cushion was proposed. This method has been successfully tested and applied in the reclamation project in Wenzhou. Based on this project, the technological process and the key technology were introduced and the reinforcement effect was analyzed. Project results showed the modified vacuum preloading method could achieve a good reinforcement effect on large area dredged fill ground in a short period. It is worth to promote the application of this method in coastal reclamation projects.

scholarly journals THE ANALYSIS OF HORIZONTAL DRAIN DESIGN IN SOFT SOIL REINCFORCEMENT

CERUCUK ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 35
Author(s):  
Hafiz Firmansyah ◽  
M. Afief Ma'ruf
Keyword(s):  
Soft Soil ◽  
Fine Sand ◽  
Soil Improvement ◽  
Quality Cost ◽  
Horizontal Drain ◽  
Vertical Drain ◽  
Access Road ◽  
Port Access ◽  
Prefabricated Vertical Drain ◽  
Horizontal Drainage

To help the process of consolidation of the soil, On the port access road Trisakti using Prefabricated Vertical Drain (PVD) materials. Of the work (PVD) thing to note is the horizontal drainage, because it was feared the absence of Horizontal Drain work item function of PVD become non-optimal even it might does not work, so the necessary design analysis of Horizontal Drain that can be used on the project. Analysis of Horizontal Drain design is intended to get the Horizontal Drain design alternatives the most optimal based on quality, cost and time.The methods used in the analysis of the design of Horizontal Drain this is a soft soil improvement method using PVD with attention to soil degradation and the planning of the heap.In the design of the installation of PVD method using static, obtained the degree of consolidation of 90% takes 9.33 months. The calculation of Horizontal Drain in the discharge value must be in flush in one horizontal drain line is  (minimum permeability). From the results of the analysis there is some material horizontal drain of qualified (in terms of time, cost and quality of workmanship) then get : Rough sand (10.93, Rp. 24.050.000.000,-, and 9.4 months), Fine sand (16.24, Rp-16,835,000,000.0, and 9.4 months), PHD (Horizontal Prefabricated Drain) (74.01, Rp-13,101,140,000.0, and 5.6 months) so that it can be concluded that the material PHD (Horizontal Prefabricated Drain) the most efficient in terms of quality, cost, and time. Keywords: Consolidation, Degrees of consolidation, Horizontal Drain, Preloading, Prefabricated Vertical Drain (PVD), Prefabricated Horizontal Drain (PHD).

scholarly journals ANALISIS PENGARUH METODE PERBAIKAN TANAH VACUUM PRELOADING TERHADAP STRUKTUR ABUTMENT DI SEKITARNYA

2021 ◽  
Vol 4 (3) ◽  
pp. 641
Author(s):  
Steven Djunawan ◽  
Andryan Suhendra
Keyword(s):  
Soft Soil ◽  
Soil Layer ◽  
Infrastructure Development ◽  
Lateral Movement ◽  
Vacuum Preloading ◽  
Consolidation Process ◽  
Distance Analysis ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Long Time

Soft soil in Indonesia is problematic in infrastructure development because of its low bearing capacity and takes a long time to consolidate. In general, the method used to overcome soft soil is vacuum preloading combined with prefabricated vertical drain, PVD. The purpose of the initial loading is to consolidate the soft soil layer with a load equal to or greater than the soil load during and after construction. Meanwhile, vertical can support the consolidation process. However, this method can also cause lateral movement which also affects the area outside the repair. Thus, it is necessary to model the influence distance analysis from the circumference of the repair area outside the repair. Analysis and modeling using 2D finite program elements that will be compared with results in field. The results of the comparison of the settlement for 260 days shows a different chart pattern but a corresponding final settlement. The modeling shows that the largest influence distance due to the lateral movement is cell 2, which is 11,23mTanah lunak di Indonesia menjadi problematika pada pembangunan infrastruktur dikarenakan daya dukung yang rendah serta memakan waktu penurunan konsolidasi yang lama. Pada umumnya, perbaikan tanah yang digunakan untuk mengatasi tanah lunak adalah vacuum preloading yang dikombinasikan dengan prefabricated vertical drain, PVD. Tujuan pembebanan awal adalah untuk mengkonsolidasikan lapisan tanah lunak dengan beban sama atau lebih besar dari beban tanah selama dan setelah konstruksi. Sementara drainase vertikal dapat mempercepat proses konsolidasi. Namun, metode ini juga dapat penyebabkan pergerakan lateral yang juga mempengaruhi area diluar perbaikan. Sehingga, dibutuhkan pemodelan analisis jarak pengaruh dari keliling daerah perbaikan ke daerah luar perbaikan. Analisis dan pemodelan menggunakan program elemen hingga 2D yang akan dibandingkan dengan hasil lapangan. Hasil perbandingan penurunan selama 260 hari menunjukan pola grafik yang berbeda namun penurunan akhir yang sesuai. Pemodelan menunjukan jarak pengaruh terbesar akibat pergerakan lateral berada pada cell 2 yaitu 11,23m.

CASE-BASED REASONING PEMILIHAN METODE KONSTRUKSI JALAN DI ATAS TANAH BERMASALAH KEDALAMAN 10 SAMPAI DENGAN 20 METER

2020 ◽  
Vol 6 (2) ◽  
pp. 77-89
Author(s):  
Maulana Iqbal ◽  
Anton Soekiman
Keyword(s):  
Soil Improvement ◽  
Soil Reinforcement ◽  
Case Based Reasoning ◽  
Vacuum Preloading ◽  
Horizontal Drain ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Case Based ◽  
Problematic Soil

Permasalahan konstruksi jalan di atas tanah bermasalah (problematic soil) tanpa adanya perbaikan  tanah (soil improvement) maupun perkuatan tanah (soil reinforcement), pada umumnya akan mengakibatkan instabilitas timbunan dan penurunan tanah dasar. Tidak sedikit jaringan jalan di atas tanah dasar bermasalah di beberapa area di Indonesia mengalami penurunan tingkat pelayanan yang drastis sebelum umur rencana. Kurangnya pemahaman karakteristik tanah dasar menyebabkan pemilihan metode konstruksi tidak efektif dan efisien. Kecenderungan pemilihan metode yang digunakan masih didasari ketersediaan pagu anggaran. Pemilihan metode konstruksi jalan di atas tanah dasar bermasalah dengan analisis Case-Based Reasoning (CBR), dapat menghemat waktu dalam pengambilan keputusan berdasarkan keahlian pakar, sehingga risiko ketidakakuratan pemilihan metode berakibat pada keputusan penanganan yang kurang tepat dapat diminimalisir. Berdasarkan hasil analisis dengan mengambil studi kasus tol Pemalang – Batang pada kedalaman tanah bermasalah antara 10 sampai dengan 20 meter dan menggunakan analisis CBR, didapatkan  gejala kecocokan (similarity) sebesar 97,74% pada metode Prefabricated Vertical Drain (PVD) yang dikombinasikan dengan metode pembebanan dengan vakum (vacuum preloading) dan Prefabricated Horizontal Drain (PHD).

scholarly journals ANALISIS DERAJAT KONSOLIDASI BERDASARKAN HASIL PEMBACAAN PIEZOMETER PADA PROYEK TOL TRANS SUMATERA

2021 ◽  
Vol 4 (2) ◽  
pp. 447
Author(s):  
Aditya Christiandi Sinulingga ◽  
Andryan Suhendra
Keyword(s):  
Theoretical Calculations ◽  
Soft Soil ◽  
Infrastructure Development ◽  
Vacuum Preloading ◽  
Goods And Services ◽  
Toll Road ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Long Time ◽  
Degree Of Consolidation

The development of toll road or expressway infrastructure in Indonesia is urgently needed because it can reduce inefficiencies due to congestion on main sections, as well as to improve the process of distribution of goods and services, especially in areas with high levels of development. Transportation infrastructure development on soft soils often experiences consolidation decline problems. Soft soil has a high moisture content and low bearing capacity. If the soft soil is saturated with water, it means that the water cannot be fully dissipated, causing the soil to take a long time to consolidate. If the construction work does not begin with land improvement, the construction has the potential to suffer damage before the planned age. To anticipate this, an alternative that can be done is to repair the soil with prefabricated vertical drain (PVD) and vacuum preloading. This study aims to determine the degree of consolidation based on the piezometer reading and to make initial predictions. As for the results of this study there is a difference of 5.79% in the degree of assessment from the results of theoretical calculations with the piezometer reading.Pembangunan infrastruktur jalan tol atau jalan bebas hambatan di Indonesia sangat dibutuhkan karena dapat mengurangi inefisiensi akibat kemacetan pada ruas utama, serta untuk meningkatkan proses distribusi barang dan jasa terutama di wilayah yang sudah tinggi tingkat perkembangannya. Pembangunan infrastruktur transportasi pada tanah lunak sering mengalami masalah penurunan konsolidasi. Tanah lunak memiliki kadar air yang tinggi dan daya dukung yang rendah. Jika tanah lunak jenuh air mengakibatkan air tidak dapat terdispasi secara penuh menyebabkan tanah membutuhkan waktu yang lama untuk terkonsolidasi. Apabila pekerjaan konstruksi tidak diawali dengan perbaikan tanah maka konstruksi tersebut berpotensi mengalami kerusakan sebelum umur yang telah direncanakan. Untuk mengantisipasi hal tersebut alternatif yang dapat dilakukan adalah melakukan perbaikan tanah dengan prefabricated vertical drain (PVD) dan vacuum preloading. Penelitian ini bertujuan untuk mengetahui besar derajat konsolidasi berdasarkan pembacaan piezometer serta melakukan prediksi awal. Adapun hasil dari penelitian ini terdapat perbedaan 5,79% derajat konsolidasi dari hasil perhitungan teoritis dengan pembacaan piezometer.

scholarly journals Analisis Alternatif Perbaikan Tanah Lunak dan Sangat Lunak pada Jalan Tol

2020 ◽  
Vol 3 (4) ◽  
pp. 1137
Author(s):  
Christian Eka Putra ◽  
Chaidir Anwar Makarim
Keyword(s):  
Bearing Capacity ◽  
Soft Soil ◽  
Soft Clay ◽  
Soil Improvement ◽  
High Water Content ◽  
Vacuum Preloading ◽  
Consolidation Process ◽  
Toll Road ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain

The existence of soft soil is one of the problems in the field of construction. Soft soil is soil that has high water content and low carrying capacity. In the case of this toll road, soil investigation at the site shows that the subgrade in the toll road planning is soft clay soil to a depth of 32 meters so that soil improvement is needed. High landfill built on soft subgrade without reinforcement will experience landslides. So it is necessary to strengthen the landfill and repair the subgrade to prevent road slides. The soil improvement methods in use are vacuum preloading and Prefabricated Vertical Drain with the vacuum functioning as an additional load. In addition to accelerating the consolidation process, the vacuum can also reduce the height of the embankment needed to achieve the desired planned road elevation. Strengthening with geotextile is also carried out on the landfill with a height of 5.94 meters so that there is no landslide on the fill. Using soil improvement methods such as vacuum preloading and prefabricated vertical drain will increase the bearing capacity of the soil so that differences in bearing capacity occur before and after repair. AbstrakKeberadaan tanah lunak menjadi salah satu masalah dalam bidang konstruksi. Tanah lunak adalah tanah yang memiliki kadar air yang tinggi dan daya dukung yang rendah. Pada kasus jalan tol ini, penyelidikan tanah di lokasi menunjukan bahwa tanah dasar pada perencanaan jalan tol merupakan tanah lempung lunak hingga kedalaman 32 meter sehingga dibutuhkan perbaikan tanah dasar. Timbunan tinggi yang dibangun di atas tanah dasar lunak tanpa perkuatan akan mengalami kelongsoran. Sehingga diperlukan perkuatan timbunan dan perbaikan tanah dasar untuk mencegah kelongsoran jalan. Metode perbaikan tanah yang digunakan adalah vacuum preloading dan Prefabricated Vertical Drain dengan vacuum berfungsi sebagai beban tambahan. Selain mempercepat proses penurunan, vacuum juga dapat mengurangi tinggi timbunan yang dibutuhkan untuk mencapai elevasi jalan rencana yang diinginkan. Perkuatan dengan geotextile juga dilakukan pada timbunan dengan tinggi yang mencapai 5.94 meter supaya tidak terjadi kelongsoran pada timbunan tersebut. Dengan menggunakan metode perbaikan tanah berupa vacuum preloading dan prefabricated vertical drain akan meningkatkan daya dukung tanah sehingga akan diketahui perbedaan daya dukung yang terjadi sebelum dan sesudah diperbaiki.

scholarly journals Influence of vertical drains on improving dredged mud by vacuum consolidation method

2018 ◽  
Vol 12 (5) ◽  
pp. 63-72
Author(s):  
Phan Huy Dong
Keyword(s):  
Soft Soil ◽  
Drainage System ◽  
Soil Improvement ◽  
Vacuum Consolidation ◽  
Vertical Drains ◽  
Fine Grained ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Reclamation Area ◽  
Preloading Method

Vacuum consolidation preloading method (VCM) has been widely adopted as an effective solution for soft soil improvement over the world. Recently, VCM has been successfully applied for improving the geotechnical properties of dredged mud, which is normally dumped at reclamation area by hydraulic pumping. However, it has been also reported that application of VCM for treatment of the dredged mud has been failed in some particular cases. The failures are mainly caused by clogging problem in vertical drains due to fine-grained soils that reduces the drainage efficiency of drainage system. To address this issue, a series of model tests have been conducted to investigate the performances of vertical drains among prefabricated vertical drain, sand drain and filter pipe. As the goal, the performances of types of the vertical drain solutions are analyzed based on the monitoring data of settlement, influencing zone surrounding the vertical drains. The test results reveal that sand drain shows the best performance among the others. In addition, the clogging problem is clearly shown in case of PVD. Keywords: dredging slurry; vacuum consolidation method; model test; PVD; filter pipe; sand drain.

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