بررسی میزان افزایش کارآمدی در روش پیش بارگذاری با خلاء در پروژه بهسازی خاک رس‌های نرم: مطالعه موردی ماهشهر خوزستان

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده عمران، دانشگاه آزاد اسلامی واحد استهبان، استهبان، ایران

2 دانشکده کشاورزی، بخش مهندسی آب دانشگاه شیراز، شیراز، ایران

چکیده

تکنولوژی اعمال پیش بارگذاری به‌وسیله خلاء سال‌ها است که در اقصی‌نقاط دنیا به طور وسیعی مورداستفاده قرار می‌گیرد. متأسفانه در ایران، هنوز پس از گذشت سال‌ها در کارهای عملی همچنان کارآمدی و نحوه عملکرد این تکنولوژی ناشناخته باقی‌مانده است. باتوجه‌به ساخت‌وسازهای صنعتی گسترده در نوار ساحلی شمال و جنوب ایران، این تکنولوژی به‌خاطر کاهش زمان ساخت و در نتیجه افزایش بهره‌وری در کل سیستم بهسازی خاک، می‌تواند نقش مهمی در پیشبرد اهداف کلی پروژه و افزایش بهره‌وری ایفا نماید. استفاده از فشار خلاء به‌منظور افزایش بهره‌وری سیستم‌های مشتمل بر بار سربار و زهکش‌های عمودی بسیار مؤثر و کارآمد است و زمان موردنیاز برای رسیدن به درجه تحکیم موردنظر را کاهش می‌دهد. در این مقاله ابتدا خلاصه‌ای از تاریخچه و اساس کارکرد سیستم‌های تحکیم خاک با خلاء ارائه شده و سپس میزان کارآمدی این سیستم با فرض به‌کاربردن آن برای یک پروژه عملی نشان داده می‌شود. تحکیم بستر واحد زلال سازی ماهشهر به‌عنوان مطالعه موردی انتخاب شده است که در آن پروژه، از بار سربار به همراه زهکش‌های عمودی (PVD ) جهت بهسازی خاک مورداستفاده قرار گرفته بود. پس از تأیید مدل، بار خلاء به میزان 30، 60 و 75 کیلوپاسکال در مدل در سه حالت وجود سربار اولیه 6 متری، سربار کاهش‌یافته 3 متری و در حالت بدون سربار اعمال گردید و میزان افزایش کارآمدی مورد بررسی قرار گرفت. باتوجه‌به نتایج به‌دست‌آمده اعمال پیش بارگذاری خلاء به میزان قابل‌توجهی باعث افزایش میزان کارآمدی هم از نظر اقتصادی و هم از نظر زمانی در سیستم بهسازی خاک در پروژه‌های مشابه می‌گردد. حالت بار سرباره کاهش‌یافته 3 متری و فشار خلاء 30 کیلوپاسکالی به‌عنوان حالت بهینه در این مطالعه مشخص گردید.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

The investigation of the Efficiency of Vacuum preloading in the reclamation of the Weak clay soil Mahshahr Khuzestan Case Study

نویسندگان [English]

  • Mohammad Mehdi Pardsouie 1
  • Seyed Mohammad Ali Zomorodian 2
  • mehdi mokhberi 1
  • seyed alireza nasehi 1
  • Mohammad Hadi Pardsouie 1
1 Iran Shiraz 214315258 Iran
2 Water Eng. Dept., Shiraz University,
چکیده [English]

Vacuum preloading technology has been widely used all over the world for years. Unfortunately, in Iran, even after years of practical work, the efficiency and functioning of this technology remain unknown. Due to the extensive industrial constructions in the north and south coast of Iran, this technology can play an important role in advancing the overall goals of the project and increasing productivity due to the reduction of construction time and as a result of increasing the productivity of the entire soil improvement system. The use of vacuum pressure in order to increase the efficiency of systems containing surcharge loads and vertical drains is very effective and efficient and reduces the time required to reach the desired degree of consolidation. In this article, first, a summary of the history and basis of operation of vacuum soil consolidation systems is provided, and then the efficiency of this system is shown assuming its use for a practical project. Substrate consolidation of the Mahshahr clarification unit has been selected as a case study in which the project used surcharge along with vertical drains (PVD) for soil improvement. After confirming the model, a vacuum load of 30, 60, and 75 kPa was applied to the model in three states of initial surcharge of 6 meters, reduced surcharge of 3 meters, and no surcharge, and the increase in efficiency was investigated. According to the obtained results, the application of vacuum preloading significantly increases the efficiency both economically and time-wise in the soil improvement system in similar projects. The reduced slag load state of 3 meters and vacuum pressure of 30 kPa were determined as the optimal scenario in this study.

کلیدواژه‌ها [English]

  • Vacuum Preloading
  • Surcharge
  • Vertical Drains
  • Consolidation
  • Weak Clay

مراجع

[1] M.S. Pakbaz, R. Alipour, Influence of cement addition on the geotechnical properties of an Iranian clay,  (2012) 1-4.
[2] R. Alipour, J. Khazaei, M.S. Pakbaz, A. Ghalandarzadeh, Settlement control by deep and mass soil mixing in clayey soil, 170(1) (2017) 27-37.
[3] J. Chu, S. Yan, B. Indraratna, Vacuum preloading techniques-recent developments and applications,  (2008).
[4] C. Rujikiatkamjorn, B. Indraratna, Current state of the art in vacuum preloading for stabilising soft soil,  (2013).
[5] B. Indraratna, C. Rujikiatkamjorn, A. Balasubramaniam, G.J.G. McIntosh, Geomembranes, Soft ground improvement via vertical drains and vacuum assisted preloading, 30 (2012) 16-23.
[6] M.R. Motahari, H. Kiani vafa, Studying Performance of PVDs on Consolidation Behavior of soft Clayey Soils Using EFM, Mahshahr Oil Storages %J Journal of Civil Engineering and Materials Application, 4(2) (2020) 75-88.
[7] B. Indraratna, R. Zhong, P.J. Fox, C.J.J.o.G. Rujikiatkamjorn, G. Engineering, Large-strain vacuum-assisted consolidation with non-Darcian radial flow incorporating varying permeability and compressibility, 143(1) (2017) 04016088.
[8] B. Indraratna, I. Sathananthan, C. Rujikiatkamjorn, A. Balasubramaniam, Analytical and Numerical Modeling of Soft Soil Stabilized by Prefabricated Vertical Drains Incorporating Vacuum reloading,  (2005).
[9] W. Kjellman, Consolidation of clay soil by means of atmospheric pressure, in:  Proc. of Conf. on Soil Stabilization, 1952, 1952.
[10] W. Zhu, J. Yan, G.J.O.E. Yu, Vacuum preloading method for land reclamation using hydraulic filled slurry from the sea: a case study in coastal China, 152 (2018) 286-299.
[11] G. Kang, T.-H. Kim, S.-K.J.J.o.O.U.o.C. Yun, Measured Performance and Analysis of the Residual Settlement of a PVD-Improved Marine Soft Ground, 20(5) (2021) 1055-1066.
[12] Y. Wu, R. Zhou, Y. Lu, X. Zhang, H. Zhang, Q.C.J.G. Tran, Geomembranes, Experimental study of PVD-improved dredged soil with vacuum preloading and air pressure,  (2022).
[13] Z.J.S.E. Ji, Foundation, Application of Vacuum Preloading Method in Narrow Road on Soft Ground Treatment Project, 36(2) (2022) 131.
[14] A. de Lillis, G. Fasano, A. Flora, S.J.P.o.t.I.o.C.E.-G.I. Miliziano, A novel application of vacuum preloading: conception, analysis and performance evaluation,  (2022) 1-16.
[15] rncc.co, construction site vacuum preloading, in, 2022.
[16] B. Indraratna, Recent advances in the application of vertical drains and vacuum preloading in soft soil stabilisation,  (2010).
[17] J. Wang, Y. Cai, J. Ma, J. Chu, H. Fu, P. Wang, Y.J.J.o.G. Jin, G. Engineering, Improved vacuum preloading method for consolidation of dredged clay-slurry fill, 142(11) (2016) 06016012.
[18] J. Cognon, I. Juran, S. Thevanayagam, Vacuum consolidation technology-principles and field experience, in:  Proceedings of the Conference on Vertical and Horizontal Deformations of Foundations and Embankments. Part 2 (of 2), Publ by ASCE, 1994, pp. 1237-1248.
[19] A. Jacob, S. Thevanayagam, E. Kavazanjian, Vacuum-assisted consolidation of a hydraulic landfill, in:  Proceedings of the Conference on Vertical and Horizontal Deformations of Foundations and Embankments. Part 2 (of 2), Publ by ASCE, 1994, pp. 1249-1261.
[20] P. Izedi Preloading and wick drain installation at Emam khomeini port in:  the first conference on soil improvement in iran, undefined, 2001.
[21] T. Fakharian , Mehdi zade , Mohammad loo the numerical modelling of radial consolidation and callibration of instrumentation data in Sarbandar Decanter center in Mahshahr, in:  forth international conference of soil mechanic and geotechnic in iran, undefined, 2010.
[22] A. Tasalloti, K. Fakharian, A. Mehdizadeh, Preliminary investigation of instrumentation in decanter units preloading project in Mahshahr port (South-west of Iran), 2010.
[23] M.C. Yapriadi, I. Sumarli, A.J.J.J.M.T.S. Iskandar, Evaluasi Settlement Menggunakan Surcharge Preloading Dengan Pvd Pada Proyek Di Bandung Selatan, 3(3) (2020) 911-922.
[24] S.M.A.Z. Mohammad Mehdi Pardsouie the investigation of the percentage of improvement in the case of applying vacuum pressure along with PVD and surcharge (part 2), in:  the second Iranian national conference  on structure , earthquake and geotechnical engineering, Mazandaran, 2011.
[25] S.M.A.Z. Mohammad Mehdi Pardsouie The numerical investigation of soil improvement of Mahshahr decanter unit with surcharge and embankment preloading ( part 1), in:  the second Iranian national conference  on structure , earthquake and geotechnical engineering, Mazandaran, 2011.
[26] M.M. Pardsouie, M. Mokhberi, M.H.J.A.R.i.C.E. Pardsouie, The Importance of Incorporating Hydraulic Modifier Function versus Step Loading in Ground Improvements Including Vacuum Preloading, 4(2) (2022) 54-60.
[27] M.M. Pardsouie, M.H. Pardsouie, S.M.A. Zomorodian, M.J.J.o.C.E. Mokhberi, M. Application, Numerical Study of efficiency of the Vacuum Preloading in Weak Clay Treatment (a case study), 6(2) (2022).
[28] J. Shang, M. Tang, Z.J.C.G.J. Miao, Vacuum preloading consolidation of reclaimed land: a case study, 35(5) (1998) 740-749.
[29] D.T. Bergado, P. Jamsawang, P. Jongpradist, S. Likitlersuang, C. Pantaeng, N. Kovittayanun, F.J.G. Baez, Geomembranes, Case study and numerical simulation of PVD improved soft Bangkok clay with surcharge and vacuum preloading using a modified air-water separation system, 50(1) (2022) 137-153.
نشریه مهندسی عمران امیرکبیر
دوره 56، شماره 9
1403
صفحه 1147-1162

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