Analysis and Modelling of Stiffened Slab Foundation on Expansive Soils

Shams, Mohamed A.; Shahin, Mohamed A.; Ismail, M.A.

doi:10.1007/978-3-319-61905-7_22

Cited by 3 publications

(1 citation statement)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among them, in terms of writing coupled seepage-soil deformation model, Wu and Vanapalli [4] developed five user material subroutines (USDFLD, UMAT, UMATHT, UEXPAN, FRIC) in ABAQUS, which were used for accessing and transmitting the stress and strain, and for calculating the stress-deflection, hydraulic behavior, expansive strains and pile-soil interface behavior, respectively. In terms of defining the wetswelling characteristics, IOP Publishing doi:10.1088/1755-1315/1330/1/012055 2 Shams and other scholars [5,6] considered the total strain of the soil as a superposition of the bulk variation due to moisture change and effective stress change, and defined soil as an elastic porous medium with wet swelling characteristic in order to study the structural deformation in expansive soils.…”

Section: Introductionmentioning

confidence: 99%

Numerical modeling bearing capacity in wetting unsaturated expansive soils

Yu,

Peng,

Qian

2024

IOP Conf. Ser.: Earth Environ. Sci.

View full text Add to dashboard Cite

To address the load-bearing deterioration of expansive soils uplift pile foundation after moisture absorption, a coupled seepage-soil deformation model for unsaturated expansive soils is implemented into ABAQUS. This modeling work consists primarily of two aspects: (1) The total strain of expansive soils has been decoupled into two parts, i.e., one caused by external loads and calculated by using Mohr-Coulomb plasticity model, and the other induced by wetting swelling and modeled by defining the moisture-swelling relation curve of expansive soils; (2) User-defined field subroutine (USDFLD) is developed by defining suction-dependent soil’s parameters (elastic modulus, cohesion and internal friction angle), and employed to simulate softening behaviors of expansive soils after moisture absorption. he above model is subsequently used to perform 3D finite element modeling and hydraulic-stress coupling analysis on the bearing capacity of pile in expansive soils before and after rainfall. Eventually, the proposed numerical method is validated by simulating a group of full-scale tests.

show abstract

Section: Introductionmentioning

confidence: 99%

Numerical modeling bearing capacity in wetting unsaturated expansive soils

Yu,

Peng,

Qian

2024

IOP Conf. Ser.: Earth Environ. Sci.

View full text Add to dashboard Cite

show abstract

Experimental Justification of the Parameters of the Soil Foundation Model Of Large-Size Slab Foundations of Multi-Story Buildings

Krotov,

Havryliuk

2024

MEC

View full text Add to dashboard Cite

In practice, the model of a linearly deformed layer of finite distribution capacity is the most widespread. The possibility of using this model for slab foundations should be confirmed by calculations with a scientific and technical justification of the accepted soil base model and its parameters. Based on observations of subsidence during the construction of a 16-story building on a slab foundation, the use of a model of the soil base in the form of a linearly deformed layer of finite distribution capacity and its parameters is demonstrated. A comparison of the measured and calculated values of the base deformation was made. The object of the study is the ground base and foundation of a 16-story residential building with an underground floor and a parking lot. During the construction, the subsidence of the building was monitored by the method of high-precision leveling of the II class. With the help of the SOFiSTiK software complex, modeling and calculation of the "foundation - foundation - building" system was performed. The soil base model is adopted as a linearly deformed layer of finite distributive capacity. The strength of the layer was limited by the size of the compressible layer. For the soil massif, the boundary conditions in the plan were adopted so that the influence of elm restrictions was minimal. The width of the model was initially set so that the distribution of compressive stresses along the depth was at an angle of distribution α=45º to the vertical from the edges of the loaded foundation. During further modeling, the distribution angle α was changed to 25º. The numerical calculation was performed using the finite element method, which is based on the solution of the theory of elasticity using the SOFiSTiK software calculation complex for the first and second groups of limit states. The possibility of applying the model of the soil base in the form of a linearly deformed layer of finite width for predicting the deformations of the building on a large-sized slab foundation based. It was established that the nature of the development of deformations determined by the calculation for the angles of distribution α=45º and α=25º is proportional to the nature of the development of subsidence determined during field observations. It has been demonstrated that the angle of distribution α=25º is optimal for modeling the soil massif of the foundation, ensuring the reliability of moment stress values.

show abstract

Numerical Analysis of Piled-Raft Foundations on Multi-Layer Soil Considering Settlement and Swelling

et al. 2022

View full text Add to dashboard Cite

Numerical modelling can simulate the interaction between structural elements and the soil continuum in a piled-raft foundation. The present work utilized a two-dimensional finite element Plaxis 2D software to investigate the settlement, swelling, and structural behavior of foundations during the settlement and swelling of soil on various soil profiles under various load combinations and geometry conditions. The field and laboratory testing have been performed to determine the behavior soil parameters necessary for numerical modelling. The Mohr–Coulomb model is utilized to simulate the behavior of soil, as this model requires very few input parameters, which is important for the practical geotechnical behavior of soil. From this study, it was observed that, as soil is soft and has less stiffness, the un-piled raft was not sufficient to resists and higher loads and exceeds the limits of settlement. Piled raft increases the load carrying capacity of soil, and the lower soil layer has a higher stiffness where the pile rests, decreasing the significant settlement. Further, the effects of (L/d) and (s/d) of the pile and Krs on the settlement are also discussed, detailed numerically under different scenarios. The swelling of expansive soil was also simulated in Plaxis 2D with an application of positive volumetric strain. The above-mentioned parametric study was similarly implemented for the heaving of foundation on expansive soil.

show abstract

Analysis and Modelling of Stiffened Slab Foundation on Expansive Soils

Cited by 3 publications

References 4 publications

Numerical modeling bearing capacity in wetting unsaturated expansive soils

Numerical modeling bearing capacity in wetting unsaturated expansive soils

Experimental Justification of the Parameters of the Soil Foundation Model Of Large-Size Slab Foundations of Multi-Story Buildings

Numerical Analysis of Piled-Raft Foundations on Multi-Layer Soil Considering Settlement and Swelling

Contact Info

Product

Resources

About