Current Science

Open Access Open Access  Restricted Access Subscription Access

Behaviour of Interfering Embedded Footings Laid in Unreinforced and Reinforced Sand Medium


Affiliations
1 Department of Civil Engineering, BMS Institute of Technology and Management, Yelahanka, Bengaluru 560 064, India
2 Department of Civil Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826 004, India
 

According to the literature, the current understanding of the interference effect on the performance of footings is with respect to surficial footings. In practice, however, the footings are laid below the ground surface. In this study, the interference behaviour of two identical strip and square footings embedded in a cohesionless, homo­geneous soil medium was examined by performing 72 laboratory model tests. The sand bed was prepared using rainfall technique and reinforced with a single biaxial geogrid layer. Parameters such as footing shape, embedment depth and the spacing between the footings were altered. Using the observed data, multiple regression analysis established a relationship between interference variables related to load-carrying capacity/settlement footing spacing and embedment depth for unreinforced and reinforced soil medium. The test results show that the embedment depth of ultimate bearing capacity and settlement affects interfering footings more than surficial footings. Strip footings are affected to a greater extent than square footings. The load-carrying capacity of two footings increases due to the enhancement of the zone of interference by 12.2% and 39.6% for the strip and square footings respectively.

Keywords

Embedded Footings, Interference, Reinforced Soil, Settlement Characteristics, Ultimate Bearing Capacity.
User
Notifications
Font Size

  • Kumar, J. and Ghosh, P., Ultimate bearing capacity of two interfering rough strip footings. Int. J. Geomech., 2007, 7, 53–62.

  • Kumar, J. and Ghosh, P., Upper bound limit analysis for finding interference effect of two nearby strip footings on sand. Geotech. Geol. Eng., 2007, 25, 499.

  • Kouzer, K. M. and Kumar, J., Ultimate bearing capacity of a footing considering the interference of an existing footing on sand. Geotech. Geol. Eng., 2010, 28(4), 457–470; doi:10.1007/s10706-010-9305-9.

  • Kumar, J. and Bhattacharya, P., Bearing capacity of two interfering strip footings from lower bound finite elements limit analysis. Int. J. Numer. Anal. Methods, 2013, 37, 441–452.

  • Ghosh, P. and Sharma, A., Interference effect of two nearby strip footings on layered soil: theory of elasticity approach. Acta Geotech., 2010, 5, 189–198.

  • Mabrouki, A., Benmeddour, D., Frank, R. and Mellas, M., Numerical study of the bearing capacity for two interfering strip footings on sands. Comput. Geotech., 2010, 37, 431–439.

  • Nainegali, L., Basudhar, P. K. and Ghosh, P., Interference of strip footings resting on nonlinearly elastic foundation bed: a finite element analysis. IJST-T. Civ. Eng., 2018, 42, 199–206.

  • Nainegali, L., Basudhar, P. K. and Ghosh, P., Interference of proposed footing with an existing footing resting on non-linearly elastic dense and loose cohesionless soil bed. Eur. J. Environ. Civ. Eng., 2021, 25(14), 2574–2591; doi:https://doi.org.10.1080/19648189.2019.1638311.

  • Ekbote, A. G. and Nainegali, L., Interference of two closely spaced strip footings embedded in cohesionless fibre-reinforced foundation soil bed. In Geo-Congress 2019: Foundations (eds Meehan, C. L. et al.), ASCE, USA, 2019, pp. 454–464.

  • Ekbote, A. G. and Nainegali, L., Interference of two closely spaced footings embedded in unreinforced and reinforced soil medium: a finite element approach using ABAQUS. Arab. J. Geosci., 2019, 12, 683–703.

  • Kumar, A. and Saran, S., Closely spaced footings on geogrid-reinforced sand. J. Geotech. Geoenviron. Eng., 2003, 129, 660–664.

  • Kumar, J. and Bhoi, M. K., Interference of two closely spaced strip footings on sand using model tests. J. Geotech. Geol. Eng., 2009, 135, 595–604.

  • Ghosh, P., Basudhar, P. K., Srinivasan, V. and Kunal, K., Experimental studies on interference of two angular footings resting on surface of two-layer cohesionless soil deposit. Int. J. Geotech. Eng., 2015, 9, 422–433.

  • Salamatpoor, S., Jafarian, Y. and Hajiannia, A., Bearing capacity and uneven settlement of consecutively constructed adjacent footings rested on saturated sand using model tests. Int. J. Civ. Eng., 2018, 17, 737–749.

  • Srinivasan, V. and Ghosh, P., Experimental investigation on interaction problem of two nearby circular footings on layered cohesionless soil. Geomech. Geoeng., 2018, 8, 97–106.

  • Saha Roy, S. and Deb, K., Interference effect of closely spaced footings resting on granular fill over soft clay. Int. J. Geomech., 2018, 19, 04018181.

  • Saha Roy, S. and Deb, K., Closely spaced rectangular footings on sand over soft clay with geogrid at the interface. Geosynth. Int., 2018, 25, 412–426.

  • Lavasan, A. A. and Ghazavi, M., Behavior of closely spaced square and circular footings on reinforced sand. Soils Found., 2012, 52, 160–167.

  • Ghazavi, M. and Dehkordi, P. F., Interference influence on behavior of shallow footings constructed on soils, past studies to future forecast: a state-of-the-art review. Trans. Geotech., 2021, 27, 100502.

  • Ghosh, P., Rajesh, S. and Sai Chand, J., Linear and nonlinear elastic analysis of closely spaced strip foundations using Pasternak model. Front. Struct. Civ. Eng., 2017, 11, 228–243.

  • Fuentes, W., Duque, J., Lascarro, C. and Gil, M., Study of the bearing capacity of closely spaced square foundations on granular soils. Geotech. Geol. Eng., 2019, 37, 1401–1410.

  • IS 650, Standard Sand for Testing Cement – Specification, Bureau of Indian Standards, New Delhi, 1991.

  • Patra, C. R., Das, B. M. and Atalar, C., Bearing capacity of embedded strip foundation on geogrid-reinforced sand. Geotext. Geomembr., 2005, 23(5), 454–462.

  • Meyerhof, G. G., Some recent research on the bearing capacity of foundations. Can. Geotech. J., 1963, 1, 16–26.

  • Das, B. M. and Larbi-Cherif, S., Bearing capacity of two closely-spaced shallow foundations on sand. Soils Found., 1983, 23(1), 1–7.

  • Boufarh, R., Abbeche, K. and Abdi, A., Experimental investigation of interference between adjacent footings on layered cohesionless soil. Soil Mech. Found. Eng., 2019, 56(2), 128–135.

  • Ghosh, P. and Kumar, P., Interference effect of two nearby strip footings on reinforced sand. Contemp. Eng. Sci., 2009, 2(12), 577–592.


Abstract Views: 85

PDF Views: 51




  • Behaviour of Interfering Embedded Footings Laid in Unreinforced and Reinforced Sand Medium

Abstract Views: 85  |  PDF Views: 51

Authors

Anupkumar G. Ekbote
Department of Civil Engineering, BMS Institute of Technology and Management, Yelahanka, Bengaluru 560 064, India
Lohitkumar Nainegali
Department of Civil Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826 004, India

Abstract


According to the literature, the current understanding of the interference effect on the performance of footings is with respect to surficial footings. In practice, however, the footings are laid below the ground surface. In this study, the interference behaviour of two identical strip and square footings embedded in a cohesionless, homo­geneous soil medium was examined by performing 72 laboratory model tests. The sand bed was prepared using rainfall technique and reinforced with a single biaxial geogrid layer. Parameters such as footing shape, embedment depth and the spacing between the footings were altered. Using the observed data, multiple regression analysis established a relationship between interference variables related to load-carrying capacity/settlement footing spacing and embedment depth for unreinforced and reinforced soil medium. The test results show that the embedment depth of ultimate bearing capacity and settlement affects interfering footings more than surficial footings. Strip footings are affected to a greater extent than square footings. The load-carrying capacity of two footings increases due to the enhancement of the zone of interference by 12.2% and 39.6% for the strip and square footings respectively.

Keywords


Embedded Footings, Interference, Reinforced Soil, Settlement Characteristics, Ultimate Bearing Capacity.

References





DOI: https://doi.org/10.18520/cs%2Fv125%2Fi4%2F392-400