scholarly journals PERANCANGAN EFEKTIVITAS PERBAIKAN TANAH DENGAN MENGGUNAKAN METODE PREFABRICATED VERTICAL DRAIN

Author(s):  
Priscilla Azzahra Chairani

<p><em>As a country that surrounded by active volcanoes, Indonesia has a very diverse clay soil content. However, in reality, clay soil is an unfavorable condition for construction activities because of its low-level of stability. Therefore, when the clay soil receives a static load on it, the soil will slowly have a settlement due to the dissipation of pore water. This settlement usually occurs over a very long period of time, thus, it is necessary to do the soil improvement using Prefabricated Vertical Drain (PVD) combined with preloading in order to shorten the time of soil consolidation so that the consolidation process becomes faster. Soil settlement analysis is calculated using two soil parameters derived from the NSPT correlation data and laboratory test data to determine the most efficient soil parameters. Furthermore, a theoretical soil improvement analysis was carried out by comparing Baron's theory and Hansbo's theory and using the Settle3D analysis program. The analysis results show that the calculation of consolidation settlement using soil parameters from laboratory test results has the closest value to the actual results in the field with a efficiency of 91%. Meanwhile, for soil improvement, the most effective PVD design was chosen using the Hansbo theory with a triangular installation pattern and a spacing of 150 cm combined with a gradual embankment.</em></p>

2015 ◽  
Vol 773-774 ◽  
pp. 1502-1507
Author(s):  
Saiful Azhar Ahmad Tajudin ◽  
Mohd Fairus Yusof ◽  
I. Bakar ◽  
Aminaton Marto ◽  
Muhammad Nizam Zakaria ◽  
...  

Construction, buildings and infrastructure founded on soft clays are often affected by settlement problem. Therefore, Prefabricated Vertical Drain (PVD) is one of the best solutions to accelerate soil consolidation by shortening the drainage path. In this study, numerical investigation was carried out to pursue a better understanding of the consolidation behavior of soft clay improved with PVD. The consolidation process accelerated by PVD with surcharge of 50 kPa was analysed using the ABAQUS software by adopting an elastic model. The aim of this study is to compare the settlement and the required time to fully consolidate the soft soil at different drain spacings (1.0 m, 1.5 m and 2.0 m) for two different thickness of the clay layer. The results shows that the time required to completely consolidate the soft soil for 12 m and 20 m thickness of clay layer with different spacings are in the range of 3 months to 66 months. The settlement rate and excess pore water pressure dissipation are increased when the spacing of the drain closer.


2016 ◽  
Vol 10 (1) ◽  
pp. 41-50
Author(s):  
Wimpie Agoeng Noegroho Aspara ◽  
Eka Nur Fitriani

AbstractIf a structure for reasons of technical, economic, social, or startegic is to be built on a soft ground, then there are usually two problems to be solved, namely the low geotechnical bearing capacity and large soil deformation with sometimes differential settlement. Pre-compression is a foundation soil compression process with the provision of temporary loading (preloading) before actually constructing a building. Pre-fabricated vertical drain is a synthetic drainage system installed vertically inside soft soil layers. Soil condition at the project activity is a relatively very soft clay soil with relatively high coefficient of consolidation resulting in very long period of consolidation process. Therefore, it is needed advance soil improvement by prealoding of pre-fabricated vertical drain. Spacings of installed PVD vary, those are 50 cm, 100 cm, 150 cm, and 200 cm with a pattern of triangles and rectangles. Based on the analytical calculation, it is resulted that optimum PVD distance to achieve 90% consolidation is 150 cm with a triangular pattern. The time of consolidation was achieved within four months. AbstrakKetika suatu struktur karena alasan-alasan teknis, ekonomi, sosial, atau strategis terpaksa didirikan di atas tanah lunak, maka biasanya ada dua masalah geoteknik yang harus dipecahkan yaitu daya dukung yang rendah dan penurunan serta beda penurunan yang besar. Prakompresi adalah suatu proses pemampatan tanah pondasi dengan jalan pemberian pembebanan sementara (prabeban/preloading) sebelum konstruksi yang sesungguhnya didirikan. Prefabricated vertical drain (PVD) adalah sistem drainase buatan yang dipasang vertikal di dalam lapisan tanah lunak. Kondisi tanah di lokasi kegiatan relatif sangat lunak dengan koefisien konsolidasi relatif sangat tinggi mengakibatkan proses konsolidasi berjalan relatif sangat lama. Untuk itu diperlukan perbaikan tanah terlebih dahulu dengan prealoading menggunakan PVD. Jarak spasi antar PVD yang dipasang bervaiasi yaitu 50 cm, 100 cm, 150 cm, dan 200 cm dengan pola konfigurasi segitiga dan segiempat. Berdasarkan hasil perhitungan secara analitis didapatkan jarak optimum PVD untuk mencapai konsolidasi 90% adalah 150 cm dengan pola segitiga dengan proses konsolidasi dicapai selama waktu penurunan 4 bulan.


2020 ◽  
Vol 3 (4) ◽  
pp. 1137
Author(s):  
Christian Eka Putra ◽  
Chaidir Anwar Makarim

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.


2020 ◽  
Vol 3 (1) ◽  
pp. 119
Author(s):  
Andreyan Prasetio ◽  
Aniek Prihatiningsih

Problem that often occurs in soft cohesive soils is settlement caused by consolidation process. If  construction activities doing when the soils has not been consolidated, settlement can occur. To accelerate  the consolidation process, soil improvement are usually do, one method of soil improvement to accelarate the consolidation process is vertical drain using prefabricated vertical drains (PVD). The soft soil layers in the field are not always continuous, sometimes found soft soil layers that have a lens layer. In this study, will discuss about the settlement and consolidation time of soft  soil layers that have a lens layer which has been improved by PVD with 1 meter distance. Infrastructure that stand on a location that is installed by PVD is taxiway and loading by Airbus A380 aircraft of 18,22ton/m2. Analysis using the 1 dimensional consolidation theory of Terzaghi. For PVD installation to a depth of 50 meters, preloading settlement of 234,80 cm with a consolidation time of  2260 days for the square pattern PVD and 1918 days for triangle pattern PVD. Post loading settlement for PVD installation depth of 50 meters by 2,50 cm. AbstrakMasalah yang sering terjadi pada tanah kohesif dan lunak adalah penurunan yang disebabkan proses konsolidasi. Penurunan dapat menyebabkan keretakan pada struktur konstruksi yang berada di atasnya. Jika suatu kegiatan konstruksi dilakukan saat tanah belum terkonsolidasi, maka konstruksi tersebut dapat mengalami penurunan.. Untuk mempercepat proses konsolidasi biasanya dilakukan perbaikan tanah, salah satu metode perbaikan tanah untuk mempercepat proses konsolidasi yaitu vertical drain dengan menggunakan prefabricated vertical drains (PVD). Lapisan tanah lunak yang terdapat di lapangan tidak selalu kontinu, terkadang ditemukan lapisan tanah lunak yang terdapat lapisan lensa. Pada penelitian ini, penulis akan membahas mengenai waktu konsolidasi yang dibutuhkan oleh lapisan tanah kohesif dan lunak yang terdapat lapisan lensa yang telah diperbaiki dengan menggunakan PVD berjarak 1 meter. Infrastruktur yang berdiri di atas lokasi yang dipasang PVD berupa taxiway dengan beban berupa pesawat Airbus A380 sebesar 18,22 ton/m2. Analisis dilakukan menggunakan teori konsolidasi 1 dimensi Terzaghi. Untuk pemasangan PVD hingga kedalaman 50 meter diperoleh penurunan pra pembebanan sebesar 234,80 cm dengan waktu konsolidasi selama 2260 hari untuk pemasangan PVD pola persegi dan selama 1918 hari untuk pola segitiga . Penurunan pasca pembebanan untuk pemasangan PVD hingga kedalaman 50 meter sebesar 2,5 cm.


Author(s):  
Murat Tonaroglu ◽  
Cem Akguner ◽  
Murat E. Selcuk

Prediction of long term settlement of soft soils below civil engineering structures is an important issue in geotechnical engineering. The data from laboratory consolidation tests are used to estimate the ultimate settlement and problems arise in predicting settlement-time behavior in the field. In order to overcome this difficulty some empirical models or adjustments have been proposed based on field settlement measurements, even if they are available at least for the early stages of loading. In this study, laboratory test results and field settlement measurements obtained for the long term settlement of clayey layers underlying the Alibey Dam in Istanbul, Turkey are used in conjunction with a model proposed by Edil and Mochtar (1984) for peat-like soils. The soil parameters of the proposed model have independently been obtained using both laboratory test data and field measurements, and model predictions are compared with actual recorded settlements. It is observed that the field measurements could be predicted more closely if the model parameters are obtained from field measurements, but predictions based on laboratory consolidation and creep test results also provide satisfactory results following the initial stages of loading.


2020 ◽  
Vol 3 (1) ◽  
pp. 69
Author(s):  
Tomy Gunawan ◽  
Alfred Jonathan S ◽  
Ali Iskandar

Investigation of soil is important to do in the planning of building construction such as foundations, piles, roads, etc. To find out the bearing capacity and parameters of the soil where a building will be built. Investigation of the soil can be done in various ways, one of which uses an electrical cone penetration test with pore water pressure. In the embankment project for the calculations on the soil so that it can be known about the settlement in soil and the length of time it reaches the hydrostatic level. Cone penetraton test is reqired and the results produce data in the form of cone resistance (qc), blanket friction (fs) and pore pressure (u) which will be processed in the CPET-IT program in order to produce soil parameters that will be used for soil settlement analysis. To find out the settlement of embankment soil, it will be supported by finite difference program. Results of studies on general is to find the effectiveness of embankment using prefabricated vertical drain (PVD) and without prefabricated vertical drain (PVD).AbstrakPenyelidikan terhadap tanah penting untuk dilakukan pada perencanaan konstruksi bangunan seperti pondasi, timbunan, jalan, dll. Untuk mengetahui daya dukung dan parameter-parameter tanah tempat akan dibangunnya sebuah bangunan Penyelidikan tanah dapat dilakukan dengan berbagai macam cara salah satunya adalah menggunakan  uji sondir elektrik dengan tekanan air pori. Pada proyek timbunan memerlukan perhitungan pada tanahnya agar dapat diketahui besarnya penurunan pada tanah dan lama waktu tanah mencapai keadaan hidrostatis. Sehingga dilakukan uji sondir secara elektrik dan dari hasil uji sondir menghasilkan data berupa tahanan konus (qc), gesekan selimut (fs) dan pore pressure (u) yang akan diolah kedalam program CPET-IT agar menghasilkan parameter-parameter tanah yang akan digunakan untuk analisis penurunan pada tanah.Untuk mengetahui besarnya penurunan pada tanah timbunan maka akan dibantu program berbasis elemen higga. Hasil studi secara umum menunjukkan seberapa besar efektivitas pada timbunan dengan menggunakan prefabricated vertical drain (PVD) dan tanpa prefabricated vertical drain (PVD).


2018 ◽  
Vol 4 (8) ◽  
pp. 1809
Author(s):  
Dao Huu Do ◽  
Nguyen Thi Phuong Khue ◽  
Phan Khac Hai

The paper builds a physical model of testing in the laboratory with the parametric tempered glass box 0.5  0.5 1.2 m (length  width  depth) containing saturated clay to study the settlement and consolidation when loading increased gradually over time. The research covers herein to present the monitoring of settlement and pore water pressure, settlement calculation, numerical simulation using PLAXIS software V8.2 based on the results of soil physical and mechanical tests before and after loading in case of having or not prefabricated vertical drain (PVD). In case of no PVD, the calculation and numerical simulation using the soil parameters before loading have the differential settlement from the monitoring data, approximately 3.86 mm (10.45%), 0.41 mm (1.11%) respectively. Meanwhile, the deviation in the case using data after loading is about 2.29 mm (6.20%), 0.21 mm (0.56%) respectively. In case of PVD, the calculation and numerical simulation with the testing result of before loading deviation from the settlement monitoring by subsidence meter is 2.91 mm (7.88%), 44.42 mm (120.28%), calculation and simulation with the testing result of after loading deviation is 0.80 mm (2.17%), 1.26 mm (3.41%). In the case of having PVD, the difference in calculation, subsidence observation, and numerical simulation between the mechanical properties before and after loading is significant, when using the mechanical data after loading then the results are quite close to the subsidence of observation and simulation rather than before loading. 


2012 ◽  
Vol 204-208 ◽  
pp. 1276-1281 ◽  
Author(s):  
Wen Tsung Liu ◽  
Chun Yi Lin

The study gives an example of the sinking pier case at Takeda Interchange of National Highway NO.3 in Taiwan. We got the monitoring data, explored the impact on the consolidation settlement of piled-raft foundation from construction procedure and soil improvement by finite element method「Plaxis8.2」and predicted the degree of post-settlement. Analytic results are shown as follows:Firstly, the soil consolidation settlement model is built by the estimated soil parameters using the data of soil exploration. The calculation value of settlement and the measured value are identical. Secondly, soil improvement only shows effective in initial stage. The pre-consolidation settlement is smaller when building embankment is before pier than when building pier is before embankment.


CERUCUK ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 35
Author(s):  
Hafiz Firmansyah ◽  
M. Afief Ma'ruf

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).


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