An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration
The evaluation of the bearing capacity of strip footings generally assumes that the soil is either dry or fully saturated, which contradicts the actual condition in nature where the soil is often in a partially saturated state. Furthermore, infiltration has a significant impact on the shear strength...
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MDPI AG
2023-08-01
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| Series: | Mathematics |
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| Online Access: | https://www.mdpi.com/2227-7390/11/16/3480 |
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| author | Sheng Xu De Zhou |
| author_facet | Sheng Xu De Zhou |
| author_sort | Sheng Xu |
| collection | DOAJ |
| description | The evaluation of the bearing capacity of strip footings generally assumes that the soil is either dry or fully saturated, which contradicts the actual condition in nature where the soil is often in a partially saturated state. Furthermore, infiltration has a significant impact on the shear strength of the soil. Following the upper bound theory of the limit analysis, this article provides a theoretical framework for assessing the bearing capacity under transient flow with linear variation in infiltration intensity for the first time. Firstly, the closed form of suction stress under linear transient infiltration is derived using Laplace transform and introduced into the Mohr–Coulomb criterion. A discrete failure mechanism with fewer variables and higher accuracy is provided to ensure kinematic admissibility. The upper bound solution for bearing capacity is obtained by solving the power balance equation. The present results are compared with results from the published literature and the finite element, confirming the validity and superiority of the theoretical framework provided. A parametric analysis is also conducted on three hypothetical soil types (fine sand, silt, and clay), and the results show that unsaturated transient infiltration has a positive influence on increasing the foundation bearing capacity. The magnitude of the influence is comprehensively controlled by factors such as soil type, saturated hydraulic conductivity, infiltration intensity, infiltration time, and water table depth. The increase in bearing capacity due to unsaturated transient infiltration can be incorporated into Terzaghi’s equation as a separate component presented in tabular form for engineering design purposes. |
| first_indexed | 2024-03-10T23:46:06Z |
| format | Article |
| id | doaj.art-f79dbb1450514a6584b512111ba2afa1 |
| institution | Directory Open Access Journal |
| issn | 2227-7390 |
| language | English |
| last_indexed | 2024-03-10T23:46:06Z |
| publishDate | 2023-08-01 |
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| spelling | doaj.art-f79dbb1450514a6584b512111ba2afa12023-11-19T02:02:39ZengMDPI AGMathematics2227-73902023-08-011116348010.3390/math11163480An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient InfiltrationSheng Xu0De Zhou1School of Civil Engineering, Central South University, Changsha 410075, ChinaSchool of Civil Engineering, Central South University, Changsha 410075, ChinaThe evaluation of the bearing capacity of strip footings generally assumes that the soil is either dry or fully saturated, which contradicts the actual condition in nature where the soil is often in a partially saturated state. Furthermore, infiltration has a significant impact on the shear strength of the soil. Following the upper bound theory of the limit analysis, this article provides a theoretical framework for assessing the bearing capacity under transient flow with linear variation in infiltration intensity for the first time. Firstly, the closed form of suction stress under linear transient infiltration is derived using Laplace transform and introduced into the Mohr–Coulomb criterion. A discrete failure mechanism with fewer variables and higher accuracy is provided to ensure kinematic admissibility. The upper bound solution for bearing capacity is obtained by solving the power balance equation. The present results are compared with results from the published literature and the finite element, confirming the validity and superiority of the theoretical framework provided. A parametric analysis is also conducted on three hypothetical soil types (fine sand, silt, and clay), and the results show that unsaturated transient infiltration has a positive influence on increasing the foundation bearing capacity. The magnitude of the influence is comprehensively controlled by factors such as soil type, saturated hydraulic conductivity, infiltration intensity, infiltration time, and water table depth. The increase in bearing capacity due to unsaturated transient infiltration can be incorporated into Terzaghi’s equation as a separate component presented in tabular form for engineering design purposes.https://www.mdpi.com/2227-7390/11/16/3480bearing capacitystrip footingsupper boundunsaturated soilstransient infiltration |
| spellingShingle | Sheng Xu De Zhou An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration Mathematics bearing capacity strip footings upper bound unsaturated soils transient infiltration |
| title | An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration |
| title_full | An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration |
| title_fullStr | An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration |
| title_full_unstemmed | An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration |
| title_short | An Analytical Framework for Assessing the Unsaturated Bearing Capacity of Strip Footings under Transient Infiltration |
| title_sort | analytical framework for assessing the unsaturated bearing capacity of strip footings under transient infiltration |
| topic | bearing capacity strip footings upper bound unsaturated soils transient infiltration |
| url | https://www.mdpi.com/2227-7390/11/16/3480 |
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