Geometrical Effect of Under-reamed Pile in Clay under Compression Load Numerical-Study

Source:
By:Ahmed M. Nasr, Waseim R. Azzam, Ibrahim S. Harran

DOI: https://doi.org/10.30564/agger.v5i1.5276

Abstract:

Recently, the use of deep foundations has increased as a result of the expansion in the construction of high-rise buildings, train tracks, and port berths. As a result of this expansion, it was necessary to use deep foundations that have low cost, high bearing loads, low settlement, and construction time, and such foundations are subjected to different types of loads such as lateral, vertical compression, and tension loads. This research paper will present one of the most important types of deep foundations that are aptly used in such structures and the most important factors affecting their bearing capacity and settlement in stiff clay. This type of deep foundation is called an under-reamed pile. The factors used in this study are pile length to diameter ratio L/D = 30, bulb diameter ratio (Du/D = 1.5, 2, 2.25, and 2.5), number of bulbs (N = 1, 2, and 3), and spacing ratio (S/D = 2 to 8). To investigate the effects of these parameters and obtain optimal results, the PLAXIS 3D was used. The analysis shows that the increase in bulb diameter increases the bearing load by 43%. Bulb spacing controls the failure mechanisms, whether cylindrical shear failure or individual failure and increases the capacity by 66% and 99%, respectively, for two and three bulbs when the bulb spacing becomes S/D = 8. When the number of bulbs increases to three, the capacity increases by 90%. If each bulb works individually, the bearing capacity doubles

References:

[1] George, B.E., Hari, G. (editors), 2015. Numer ical investigation of under-reamed piles finite element analysis was carried out using. Sixth International Geotechnical Symposium 6 IGS Chennai, India. p. 4-7. [2] Pakrashi, S., 2017. A comparative study on safe pile capacity as shown in table 1 of IS 2911 (Part III): 1980. Journal of The Institution of Engineers (India): Series A. 98(1-2), 185-199. DOI: https://doi.org/10.1007/s40030-017-0189-z [3] Terzaghi, K., 1942. Discussion of the progress report of the committee on the bearing value of pile foundations. Proceedings of the American Society of Civil Engineers. 68, 311-323. [4] Vali, R., Mehrinejad-Khotbehsara, E., Saberian, M., et al., 2019. A three-dimensional numerical comparison of bearing capacity and settlement of tapered and under-reamed piles. International Journal of Geotechnical Engineering. 13(3), 236-248. DOI: https://doi.org/10.1080/19386362.2017.1336586 [5] Kurian, N.P., Srilakshmi, G. (editors), 2004. Studies on the geometrical features of under-reamed piles by the finite element method. Proceedings of International e-Conference on ‘Modern Trends in Foundation engineering: Geotechnical Challenges and Solutions, Madras; 2004 Jan. p. 14. [6] Golait, Y.S., Satyanarayana, V., Raju, S. (editors), 2009. Concept of under-reamed cemented stone columns for soft clay ground improvement. GeoTide. Guntur, Indian Geotechnical Society, IGC. New Delhi: Allied Publishers New Delhi. p. 356-360. [7] Alielahi, H., Mardani, Z., Daneshvar, S., 2014. Arrangement optimization of asymmetric under-reamed pile groups in order to evaluate tensile bearing capacity using numerical model. 8th National Congress on Civil Engineering; 2014 May 7-8; Babol, Iran. Babol: Babol Noshirvani University of Technology. [8] Mohan, D., Murthy, V.N.S., Jain, G.S., 1969. Design and construction of multi-under-reamed piles. Proceedings the Seventh International Conference on Soil Mechanics and Foundation Engineering, Session 2, Mexico. Mexico: Mexico City. pp. 183. [9] Martin, R.E., DeStephen, R.A., 2019. Large diameter double under-reamed drilled shafts. Journal of Geotechnical Engineering. 109(8), 1082-1098. DOI: https://doi.org/10.1061/(ASCE)0733-9410(1983)109:8(1082) [10]Jain, G.S., Gupta, S.P., 1972. Deformation of soil around a multi under-reamed pile. Indian Concrete Journal. 46(6), 239-241. [11] Peter, J.A., Lakshmanan, N., Manoharan, P.D., 2006. Investigation on static behavior of self compacting concrete under-reamed piles. Journal of Materials in Civil Engineering. 18(3), 408-414. DOI: https://doi.org/10.1061/(ASCE)0899-1561(2006)18:3(408) [12]Majumder, M., Chakraborty, D., Kumawat, V., 2022. Model test study on single and group under-reamed piles in sand under compression and tension. Innovative Infrastructure Solutions. 7, 129. doi: https://doi.org/10.1007/s41062-021-00725-4 [13]Yuan, L., Dai, G., Gong, W., 2014. Experimental investigation, calculation and analysis of compressive bearing capacity of squeezed branch piles. Hans Journal of Civil Engineering. 3, 103e9. [14]Tian, W., Qian, Y., Lu, T., et al., 2016. The undisturbed soil experiment of the comparison about the failure of the half and whole cross-section piles under the resistance compression. International Forum on Energy, Environment & Sustainable Development. 75, 296-300. DOI: https://doi.org/10.2991/ifeesd-16.2016.51 [15]Zhang, M., Xu, P., Cui, W., et al., 2018. Bearing behavior and failure mechanism of squeezed branch piles. Journal of Rock Mechanics and Geotechnical Engineering. 10(5), 935-946. DOI: https://doi.org/10.1016/j.jrmge.2017.12.010 [16]IS:2911, 1980. Indian standard code of practice for design and construction of pile foundations. Part III: Under-reamed piles (first revision). Soil and Foundation Engineering. New Delhi: Bu reau of Indian Standards. [17]No, P., 1990. Drilled shafts: Construction procedures and design methods. Tunnelling & Under ground Space Technology. 5(1-2), 156-157. DOI: https://doi.org/10.1016/0886-7798(90)90101-o [18]Qian, Y., Yi, Y., Wang, R., 2013. Research on in fluence factors of the ultimate bearing capacity of the soil of push-extend multi-under-reamed pile under compression. Advances in Materials Research. 671-674, 538-541. DOI: https://doi.org/10.4028/www.scientific.net/AMR.671-674.538 [19]Xie, X., Yin, X., 2012. The finite element analysis of plate’s distance on push-extend multi under-reamed pile. Advances in Materials Research. 468-471, 2517-2520. DOI: https://doi.org/10.4028/www.scientific.net/AMR.468-471.2517 [20]Qian, Y.M., Shan, L.J., Xu, G.H., 2014. Testing research on the shape of the bearing push-extend reamed affecting the bearing capability of the pile of push-extend multi-under-reamed pile. Advances in Materials Research. 962-965, 1091-1094. DOI: https://doi.org/10.4028/www.scientific.net/AMR.962-965.1091 [21]George, B., Hari, G., Alexander, C., 2022. Investigation on multi under-reamed piles with small bulb diameter in clay. International Journal of Geotechnical Engineering. 16(4), 462-470. DOI: https://doi.org/10.1080/19386362.2021.1959010 [22]Peter, J.A., Lakshmanan, N., Devadas Manoharan, P., 2006. Investigations on the Static Behavior of Self-Compacting Concrete Under-Reamed Piles. Journal of Materials in Civil Engineering. 18(3), 408-414. DOI: https://doi.org/10.1061/(ASCE)0899-1561(2006)18:3(408) [23]Qian, Y.M., Liu, X.L., Wang, R.Z., 2013. Research on the formula of the height of bearing push-extend under-reamed of the push-extend multi-under-reamed pile. Advances in Materials Research. 694(697), 883-886. DOI: https://doi.org/10.4028/www.scientific.net/AMR.694-697.883 [24]Qian, Y.M., Zhai, R.Z., Liu, X.L., 2014. Testing research is about the influence of the diameter of the bearing push-extend reamed to the bearing capability of the pile of push-extend multi under-reamed pile. Applied Mechanics and Materials. 578-579, 192-195. DOI: https://doi.org/10.4028/www.scientific.net/AMM.578-579.192 [25]Qian, Y.M., Zhao, D.P., Xie, X.W., 2014. The research on the ultimate bearing capacity of soil around the push-extend multi-under-reamed pile at sliding failure state. Applied Mechanics and Materials. 578-579, 232-235. DOI: https://doi.org/10.4028/www.scientific.net/AMM.578-579.232 [26]Qian, Y., Chen, X., Xie, X., 2014. Determine the stress calculating mode of sliding failure of soil mass under the push-extend multi-under-reamed pile. Engineering. 6(5), 254-259. DOI: https://doi.org/10.4236/Eng.2014.65029 [27]Qian, Y., Xu, G., Wang, R., 2013. Experimental research on failure behavior of soil around pile under compression. Telkomnika Indonesian Journal of Electrical Engineering. 11(4), 23-77. http://journal.esperg.com/index.php/tijee/article/view/2187 [28]Qian, Y.M., Yu, H., Wang, R.Z., 2013. Analyzing bearing capacity influence due to location of bearing push-extend reamed of the push-extend multi-under-reamed pile. Advanced Materials Research. 690(693), 1891-1894. DOI: https://doi.org/10.4028/www.scientific.net/AMR.690-693.1891 [29]Shrivastava, N., Bhatia, N., 2008. Ultimate bearing capacity of under-reamed pile—Finite element approach. 12th International Conference on Computer Methods and Advances in Geomechanics. 5, 3490-3497 [30]Liu, Y., Liu, H., Lin, D., 2011. Based on FEM in analysis of the performance of under-reamed pile expansion of the bottom. PACCS 2011 2011 3rd Pacific-Asia Conference Circuits, Communications & System; 2011 Jul 17-18; Wuhan,China. USA: IEEE. p. 5-8. DOI: https://doi.org/10.1109/PACCS.2011.5990151