Enlarged base stone columns

Other Title(s)

الأعمدة الحجرية ذات القاعدة الواسعة

Dissertant

al-Sudani, Kawthar Yali Husayn

University

University of Technology

Faculty

-

Department

Department of Building and Construction Engineering

University Country

Iraq

Degree

Master

Degree Date

2006

English Abstract

The present work is focused towards investigating the feasibility of using enlarged base stone column to achieve further improvement in terms of bearing capacity and settlement as compared to the ordinary stone column.

The parameters involved in this study are the area replacement ratio, length of stone column to diameter ratio, diameter of enlarged base to length of column ratio.

In addition to the evaluation of the stress concentration ratio for both traditional and enlarged base stone column.

Model tests were performed using steel container (600 x 600 x 500 mm).

The bed of soft soil with untrained shear strength ranging from (ll-14kN / m2) was prepared in this container and different configurations of stone columns were constructed in these beds of soil.

Model footing was selected according to the specified area replacement ratio and placed centrally on the bed of soil.

These model footing were loaded statically and the generated settlement were recorded.

Results are presented in terms of bearing improvement ratio defined as (the ratio of applied stress to the untrained shear stern: treated models to same ratio for the untreated soil).

On the other hand the results of the generated settlement are represented as the settlement reduction ratio defined as (the ratio of the settlement of the treated soil to the settlement of the untreated soil).

Both terms are used for enlarged base and traditional stone columns.

The optimum results of enlarged base stone columns provided bearing improvement ratio of 2.45, 2.74, 3.27 and 3.82 for Ls / Ds ratio is 1, 2, 4 and 6 respectively at area replacement ratio Ar = 0.4, and the bearing improvement ratio of 3.57, 4.14, 4.76 and 5.62 for L s / Ds ratio is 0.76, 1.52, 3.U4.and 4.jp respectively at area replacement hose results as compared to the corresponding tradition column show 1.17, 1.31, 1.46, 1.64, 1.81, 2 and 2.2 in bearing improvement ratio for Ls / Ds ratio is 1, 2, 3, 4, 5, 6 and 7 respectively at area replacement ratio Ar = 0.4, and show 1.87, 2.0, 2.15 and 2.42 in bearing improvement ratio for Ls / Ds ratio is 0.76, 1.52, 3.04 and 4.56 respectively at area replacement ratio Ar = 0.69.

The corresponding settlement reduction ratio reached 0.53, 0.48, 0.24 and 0.19 for Ls / Ds ratio is 1, 2, 4 and 6 respectively at area replacement ratio Ar = 0.4, and the settlement reduction ratio of 0.27, 0.24, 0.2 and 0.17 for Ls / Ds ratio is 0.76, 1.52, 3.04 and 4.56 respectively at area replacement ratio Ar = 0.69.

Main Subjects

Civil Engineering

Topics

• Mechanics
• Soil physics
• Soil mechanics
• Columns

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-305918