Expansive soils are the most problematic soils due to their property of swelling and expansion with the influence of variable moisture, a number of civil engineering structures were destroyed. A billions of US dollars spent worldwide each year to mitigate the problem. The presence of expansive sub-grade soil results pavement distress and damage. Removing the expansive soil and replacing with the competent material is applied to mitigate the problem which is very expensive and time consuming for long hauling distance and thick layer expansive soil. This study presented stabilization of local expansive sub-grade soil using marble waste powder with lime.
The marble waste powder was collected in Addis Ababa from Ethiomarble processing enterprise Gulele branch and the lime was collected at Gast Solar Mechanics in Addis Ababa. Free swell index test, Atterberg limit test, Proctor test, unconfined compressive test, California Bearing Ratio Tests, swelling potential and swelling pressure test were used to evaluate properties of treated and untreated soils. The expansive subgrade soil was treated using 5%, 10%, 15%, 20%, and 25% marble waste powder with fixed 3% lime respective combinations by weight of the soil. The optimum percent combination for this study was 10% marble waste powder with 3%lime based on soaked CBR swell, soaked CBR, swelling pressure and swelling potential test result values. Optimum proportion of stabilizers improve CBR Value from 0.65% to 4.19%, reduce swelling pressure from 1000kpa to 440kpa, increases MDD from 1.21 to 1.29, and reduce PI from 78% to 48.4%. Keywords: marble waste powder, lime, expansive soil, CBR, UCS, swelling pressure, MDD, OMC
Table of Contents
1. INTRODUCTION
1.1. Background
1.2. Problem statement
1.3. Objective
1.4. Justification
1.5. Scope of the work
1.6. Methodology of the report
1.7. Organization of the report
2. LITERATURE REVIEW
2.1. Distribution of expansive soil
2.1.1. Worldwide distribution of expansive soil
2.1.2. Distribution of expansive soil in Ethiopia
2.2. Mineralogical composition of expansive soils
2.3. Identification
2.3.1. Field identification
2.3.2. Laboratory identification
2.4. Damaging effect of expansive sub-grade soils
2.5. Mitigating the effect of expansive sub-grade soils
2.5.1. Soil replacement
2.5.2. Surcharge loading
2.5.3. Pre-wetting
2.5.4. Moisture control
2.5.5. Compaction control
2.5.6. Grouting
2.5.7. Mechanical stabilization
2.5.8. Chemical stabilization
2.5.9. Lime stabilization
2.5.10. Marble waste powder stabilization
3. METHODOLOGY
3.1. Materials used for testing
3.1.1. Expansive subgrade soil sample
3.1.2. Lime
3.1.3. Marble Waste Powder
3.1.4. Availability of marble waste powder in Ethiopia
3.2. Preparation and designation of test samples
3.3. Test procedure
3.3.1. Atterberg limits test
3.3.2. Grain size analysis test
3.3.3. Specific gravity test
3.3.4. Compaction test
3.3.5. California bearing ratio test
3.3.6. Twenty four hour free swell test
3.3.7. Unconfined compressive strength
3.3.8. One-dimensional swell consolidation
4. RESULTS AND DISCUSSION
4.1. Property of Bole-arabsa condominium project-13 untreated soil
4.1.1. Particle size analysis
4.1.2. Laboratory compaction test
4.1.3. Specific gravity of soil solids by water pycnometer
4.1.4. Atterberg limits
4.1.5. Classification
4.1.6. Free swell index
4.1.7. Unconfined comprehensive strength
4.1.8. California Bearing Ratio
4.2. Effect of lime on soil PH
4.3. Effect of stabilizer on Atterberg limit test
4.4. Effect of stabilizers on moisture density relationship characteristics
4.5. Effect of stabilizers on unconfined compressive strength (UCS) of soil
4.6. The effect of stabilizers on 24hour free swell index (FSI)
4.7. Effect of stabilizers on California Bearing Ratio (CBR)
4.8. Effect of stabilizers on swelling pressure test
5. CONCLUSIONS
6. RECOMMENDATION
Objective and Thematic Scope
This study aims to investigate the stabilization of local expansive subgrade soils by utilizing marble waste powder in combination with lime to minimize pavement damage and identify the optimal mix proportions for enhancing engineering properties.
- Stabilization of expansive subgrade soils using industrial byproducts (marble waste powder and lime).
- Characterization of untreated and treated soil through index and mechanical laboratory tests.
- Evaluation of engineering properties including CBR, UCS, and swelling potential.
- Development of a sustainable and cost-effective waste disposal and soil improvement strategy for road construction in Ethiopia.
Excerpt from the Book
1.1. Background
Almost every civil engineering structures, bridges, highways, buildings, canals, dams, walls, or tunnels, must be in or on the surface of the earth. For satisfactory performance, each structure must have suitable foundation soil.
Expansive soils are soils that swell when subjected to moisture and shrink when they dry. The presence of expansive soil doesn’t cause a problem at constant moisture content. However, at the situation of repeated moisture variations swelling and shrinkage are not fully reversible processes. The process of shrinkage causes cracks, which on re-wetting, do not close-up perfectly and hence cause the soil to bulk-out slightly, and also allow enhanced access to water for the swelling process. In geological time scales shrinkage cracks may become in-filled with sediment, thus imparting heterogeneity to the soil. When material falls into cracks the soil is unable to move back, thus resulting in enhanced swelling pressures. This cyclic movement create a problem for civil engineers to construct on expansive soils and cause considerable damages to civil engineering structures including pavements. Construction of pavements over expansive soils leads poor performance due to development of cracks induced by moisture variation. The presence of clay mineral montmorillonite is known to be responsible for expansive nature of these soils.
Summary of Chapters
1. INTRODUCTION: This chapter outlines the thesis background, problem statement, research objectives, scope, and the methodology employed for the study.
2. LITERATURE REVIEW: This chapter provides an overview of expansive soils, their worldwide and local distribution, damaging effects, and various existing mitigation measures.
3. METHODOLOGY: This chapter details the materials used, experimental designs, standard testing procedures, and parameters adopted for both treated and untreated soil samples.
4. RESULTS AND DISCUSSION: This chapter presents the laboratory test findings, providing a detailed analysis and discussion regarding the performance of the stabilized soils.
5. CONCLUSIONS: This chapter summarizes the findings regarding the impact of marble waste powder and lime on the index and engineering properties of the soil.
6. RECOMMENDATION: This chapter offers suggestions for practical application and outlines directions for future research on the stabilization of expansive soils.
Keywords
marble waste powder, lime, expansive soil, CBR, UCS, swelling pressure, MDD, OMC, stabilization, subgrade, pavement, soil mechanics, civil engineering, geotechnical engineering, Addis Ababa.
Frequently Asked Questions
What is the core focus of this research?
The research focuses on the stabilization of weak, locally sourced expansive subgrade soils using a combination of marble waste powder and lime to prevent pavement damage.
What are the primary fields covered in this document?
The document covers geotechnical engineering, soil stabilization techniques, road construction materials, and environmental waste management practices.
What is the main objective of this study?
The main objective is to characterize the behavior of stabilized versus non-stabilized expansive soils and to determine an optimal mix ratio of marble waste powder and lime to enhance engineering characteristics.
Which scientific methods are applied in this work?
The study employs a range of standard laboratory tests, including Atterberg limits, Proctor compaction tests, CBR, unconfined compressive strength, and one-dimensional swelling pressure tests.
What topics are discussed in the main body?
The main body discusses the background of expansive soils, their mineralogical properties, existing mitigation techniques, the specific material testing procedures, and an analysis of how stabilizers affect soil density, strength, and swelling potential.
Which keywords best characterize this work?
Key terms include marble waste powder, expansive soil, CBR, UCS, swelling pressure, soil stabilization, and subgrade material.
What was the identified optimal mix ratio?
The study concluded that the optimal mix for the specific local expansive soil is 87% soil, 10% marble waste powder, and 3% lime.
How does the addition of marble waste powder affect soil properties?
The study indicates that proper addition of the stabilizers increases Maximum Dry Density (MDD), enhances CBR values, and significantly reduces the plasticity index and swelling pressure of the expansive soil.
- Arbeit zitieren
- Amdegebreal Endalew (Autor:in), 2016, Stabilization of Local Expansive Subgrade Soil using Marble waste powder with Lime, München, GRIN Verlag, https://www.grin.com/document/520373
