Evaluation of Total Stress and Arching Coefficient by Back Analysis with Result of Stepwise Construction (Case Study: Marvak Earth Dam)

Document Type : Original Article

Authors

1 Assistant Professor, Department of Civil Engineering, University of Ayatollah Ozma Boroujerdi, Boroujerd, Iran

2 Ms. Graduated, Water Engineering and Hydraulic Structures, Ayatollah Boroujerdi University

3 Assistant Professor, Water Engineering and Hydraulic Structure Ph.D., Department of Civil Engineering, Faculty of Engineering, University of Ayatollah ozma Borujerdi, Borujerd, Iran

Abstract

 
 Arching in core dam can reduce tension and create scour and clay scrub damage, so it is always a major issue in the earth's dams. In this research, Geostudio software, which is a powerful software for limited components, is used to study the total stress and aridity coefficient of Marvak earth dam. In modeling the dam, a Mohr-Coulomb behavioral model has been used and the effect of the construction has been considered. By analyzing the stress-strain during the construction of the dam and the effect of the construction, the results of total stress and arching coefficient were evaluated and compared with the results of the instrumentation. Multivariate regression and coefficient of determination were used to fit the observed and predicted data and the value of R2= 0.9834 was obtained, which is a very good agreement between the observed and predicted arching data. The results indicate that as the embankment increases, the total stresses also increase, and the highest arching percentage from the beginning to the end of the construction phase is 58 percent and at the third of the core of the foundation. Due to the great effect of consolidation on the arching severity, the speed of construction should be chosen in such a way as to be part of the consolidation of the underlying layers before the upper layers are applied. It is also possible to reduce arching by choosing the appropriate filter between the core and the shell and using materials with a Poisson's ratio.

Keywords

Main Subjects

References

جمال، ع.، نیکو، م.ر.، کریمی، ا.، 1390. افزایش ایمنی در برابر وقوع شکست هیدرولیکی در سدهای خاکی غیر همگن، هسته رسی قائم یا مایل، اولین کنفرانس بین المللی و سومین کنفرانس ملی سد و نیروگاه‌های برق آبی.
حشمتی، ع. ا.، یوسفی، م.، 1388. تحلیل عددی سد دریک و تأثیر پارامترهای مدل موهر-کولمب بر تنش‌های نرمال هسته رسی، مجله عمران شریف، 38 (2): 69-61
عساکره، ع.، آهنگ،م.، 1396. بررسی عددی پدیده قوس‌زدگی در هسته سد خاکی غیرهمگن بافت واقع در استان کرمان، عمران مدرس، 17(5): 168-161.
میرقاسمی. ع.ا.، توللی. ع.،  1379. تحلیل سه بعدی انتقال تنش در هسته رسی سدهای خاکی واقع در دره‌های تنگ، چهارمین کنفرانس سدسازی، تهران، ایران.
نوری قیداری، م.ح.، علی‌الهی، ح.، ملائی، ر.، 1393. بررسی تنش کل در سدخاکی گلابر با استفاده از تحلیل عددی و مقایسه آن با نتایج ابزاردقیق، همایش ملی معماری، عمران و توسعه نوین شهری، تبریز، ایران.
Dunicliff, j. 1993. Geotechnical Instrumentation for Monitoring Field Performance, Published by Wiley.
Gao, J.L., Chen, Y.X., 2012. Study on stress of closed cut-off wall in earth-rock Dam reinforcement
He, X.X., Wang, R.J., YAN, F., FAN, Y.X., 2016. Effect of seepage-stress coupling on
Kulhawy, F.H, 1976. Load Transfer and Hydraulic Fracturing in Zoned Dams. Journal of Geotechnical Engineering, 102(9): 963–967.
Liu, S., Wang, L., Wang, Z.J., Bauer, E., 2016. Numerical stress-deformation analysis of cut-off wall in clay-core rock fill dam on thick overburden, Water
Maksimovic, M, 1973.Optimal Position of Central Clay Core of Rock-Fill Dam in Respect to Arching and Hydraulic Fracture.  International Congress on Large Dam, pp. 789-800.
Overburden Dam. Advanced Materials Research, 393-395: 463-466
Science and Engineering, 9(3): 219-226
Sherard, J.L, 1986. Hydraulic Fracturing in Embankment Dam. Journal of Geotechnical Engineering, 112(100: 905-927.
Skibin, G.M., Chizh, I.N., 2016. Evaluation of Cutoff Walls Influence on Stresses Distribution
Stress and deformation of cutoff wall. 5th International Conference on Civil, Architectural and Hydraulic Engineering, Shaanxi, China, 843-850.
Szostak, A., Massie´ra,M. 2005.Use of deformation monitoring results in solving geotechnical problems case studies. Journal of engineering geology, 97:3-12.
Zhang, B., 2012. The Stress and Displacement Analysis of the Cut-Off Wall for the Deep under Adjacent Foundations. International Conference on Industrial Engineering, Novocherkassk, Russia, 150: 2261-2265.

Files

Share

How to cite

Statistics