تحلیل عددی

Due to rapid growth in infrastructure sector, the construction of high-rise buildings is becoming very popular among all the countries. Engineers face significant issues with high rise buildings, particularly in terms of structural and foundation aspects. Many old design approaches can't be used with certainty since they involve extrapolation far beyond the domains of existing experience, hence structural and geotechnical engineers are being compelled to use more advanced analysis and design methodologies. The current study is an attempt to predict the bearing capacity and settlement behavior of piled-raft footing when embedded into cohesionless deposit. The numerical analysis has been carried out to examine the effect of numerous key parameters of pile and raft such as pile length (10, 15, 20 m), pile diameter (0.3, 0.4, 0.5 m), pile number (16, 20, 24), pile spacing (2D, 3D, 4D) (where “D” is diameter of the pile), raft thickness (0.4, 0.5, 0.6 m), and angle of internal friction of soil (25°, 30°, 35°) on load-settlement behavior of the piled- raft foundation using ABAQUS software. A constant spacing between the piles, i.e. 3D was used throughout the analysis. The results of numerical investigation revealed an improvement in bearing capacity and a reduction in settlement value on increasing length, diameter and number of piles and also with increasing angle of internal friction. The current study not only increases the bearing capacity of the foundation but provides a cost-effective foundation technique to engineers.

According to the wide application of segmental lining in mechanized tunneling, recognizing the behavior of segmental lining joints is important in tunnels designing. In the structural analysis of the tunnel segmental lining, segmental joints can be considered as elastic joints, and their stiffness characteristics are affected by the rotational, shear, and axial stiffness. The purpose of this work is to investigate the effect of the rotational, shear, and axial stiffness of segmental lining joints on the internal forces (bending moment and axial force)under the static conditions. For this purpose, a 3D numerical analysis was carried out using the ABAQUS software. The results obtained show that by increasing the rotational stiffness of the segmental joint, the bending moment increases, and for lower values of rotational stiffness, the bending moment variations are higher, while the axial force variations are very slight in comparison with the bending moment. By increasing the axial and shear stiffness of the segmental joint, changes of the bending moment and axial force in segmental lining are negligible.