The Effect of Metakaolin Usage in Subgrade on Flexible Pavement Design

Tacettin Geçkil; Talha Sarıcı; Bahadır Karabaş

Article Details

The Effect of Metakaolin Usage in Subgrade on Flexible Pavement Design

Authors:

Tacettin Geçkil | Talha Sarıcı | Bahadır Karabaş

Publisher:

Giresun University

Main Topics:

İnşaat Geoteknik Mühendisliği | Ulaştırma Mühendisliği

Journal:

Karadeniz Fen Bilimleri Dergisi Vol.15 Issue 1, pp.99-118

Document Type:

Article

Publication Date:

3/2025

Document Language:

Turkish

Document ID (Org No.):

2001342303

pISSN:

2564-7377

Keywords:

Abstract:

 In this study, the effects of a road subgrade stabilized with metakaolin obtained from kaolin clay on the flexible pavement layers designed above it were examined in terms of layer thickness and construction costs. In the first stage of the research, tests were conducted to determine the properties of the soil samples. Subsequently, proctor compaction tests were performed on samples prepared by adding metakaolin to the soil at weight ratios of 3, 6, 9, and 12. Following these tests, unconfined compression test samples were prepared and tested after a 28-day curing period. The results showed that the highest compressive strength was achieved in mixtures containing 6 metakaolin. Additionally, unmodified and 6 metakaolin-modified samples were subjected to California bearing ratio CBR tests after a 28-day curing period. It was found that the CBR value of samples containing 6 metakaolin increased by 95.44. Using these CBR values, the thickness and costs of pavement layers were calculated based on the 1993 flexible pavement design principles of the American Association of State Highway and Transportation Officials AASHTO. The calculations revealed that stabilizing the subgrade with 6 metakaolin reduced the pavement layer thicknesses by 35.29 and construction costs by 5.59.

 In this study, the effects of a road subgrade stabilized with metakaolin obtained from kaolin clay on the flexible pavement layers designed above it were examined in terms of layer thickness and construction costs. In the first stage of the research, tests were conducted to determine the properties of the soil samples. Subsequently, proctor compaction tests were performed on samples prepared by adding metakaolin to the soil at weight ratios of 3, 6, 9, and 12. Following these tests, unconfined compression test samples were prepared and tested after a 28-day curing period. The results showed that the highest compressive strength was achieved in mixtures containing 6 metakaolin. Additionally, unmodified and 6 metakaolin-modified samples were subjected to California bearing ratio CBR tests after a 28-day curing period. It was found that the CBR value of samples containing 6 metakaolin increased by 95.44. Using these CBR values, the thickness and costs of pavement layers were calculated based on the 1993 flexible pavement design principles of the American Association of State Highway and Transportation Officials AASHTO. The calculations revealed that stabilizing the subgrade with 6 metakaolin reduced the pavement layer thicknesses by 35.29 and construction costs by 5.59.

 In this study, the effects of a road subgrade stabilized with metakaolin obtained from kaolin clay on the flexible pavement layers designed above it were examined in terms of layer thickness and construction costs. In the first stage of the research, tests were conducted to determine the properties of the soil samples. Subsequently, proctor compaction tests were performed on samples prepared by adding metakaolin to the soil at weight ratios of 3, 6, 9, and 12. Following these tests, unconfined compression test samples were prepared and tested after a 28-day curing period. The results showed that the highest compressive strength was achieved in mixtures containing 6 metakaolin. Additionally, unmodified and 6 metakaolin-modified samples were subjected to California bearing ratio CBR tests after a 28-day curing period. It was found that the CBR value of samples containing 6 metakaolin increased by 95.44. Using these CBR values, the thickness and costs of pavement layers were calculated based on the 1993 flexible pavement design principles of the American Association of State Highway and Transportation Officials AASHTO. The calculations revealed that stabilizing the subgrade with 6 metakaolin reduced the pavement layer thicknesses by 35.29 and construction costs by 5.59.

 Bu çalışmada, kaolin kilinden elde edilen metakaolin kullanılarak stabilize edilen yol tabanının üzerine tasarlanan esnek bir üstyapıda, bu ıslahın etkileri, tabaka kalınlığı ve yapım maliyeti açısından incelenmiştir. Araştırmanın ilk aşamasında, zemin örneklerinin özellikleri deneysel çalışmalar ile belirlenmiştir. Ardından, zemin örneklerine ağırlıkça 3, 6, 9 ve 12 oranlarında metakaolin ilave edilerek hazırlanan numunelere proktor deneyleri uygulanmıştır. Bu işlemleri takiben, hazırlanan serbest basınç deneyi numuneleri, 28 gün kür sonrasında test edilmiştir. Deneyler sonucunda, en yüksek basınç dayanımının 6 metakaolin içeren karışımlarda elde edildiği belirlenmiştir. Ayrıca, katkısız ve 6 metakaolin katkılı numuneler, 28 gün kür sonrası Kaliforniya taşıma gücü oranı CBR deneyine tabi tutulmuş ve 6 metakaolin içeren numunelerin CBR değerinin 95,44 oranında arttığı tespit edilmiştir. Elde edilen bu CBR değerleri kullanılarak, Amerikan Devlet Karayolları ve Ulaştırma Birliği AASHTO 1993 esnek yol üstyapı tasarım esaslarına göre üstyapı tabaka kalınlıkları ve maliyetleri hesaplanmıştır. Yapılan hesaplamalar sonucunda, 6 metakaolin ile stabilize edilen yol tabanı sayesinde üstyapı tabaka kalınlıklarının 35,29 oranında, maliyetlerin ise 5,59 oranında azaldığı belirlenmiştir.

Article Details

The Effect of Metakaolin Usage in Subgrade on Flexible Pavement Design

Authors:

Tacettin Geçkil | Talha Sarıcı | Bahadır Karabaş

Publisher:

Giresun University

Main Topics:

İnşaat Geoteknik Mühendisliği | Ulaştırma Mühendisliği

Journal:

Karadeniz Fen Bilimleri Dergisi Vol.15 Issue 1, pp.99-118

Document Type:

Article

Publication Date:

3/2025

Document Language:

Turkish

Document ID (Org No.):

2001342303

pISSN:

2564-7377

Low plasticity clay

Metakaolin

stabilization

CBR

Flexible pavementDüşük plastisiteli kil

Metakaolin

Stabilizasyon

CBR Esnek üst yapı

Issues

Article Details

Authors: Tacettin Geçkil | Talha Sarıcı | Bahadır Karabaş

Publisher: Giresun University

Main Topics: İnşaat Geoteknik Mühendisliği | Ulaştırma Mühendisliği

Journal: Karadeniz Fen Bilimleri Dergisi Vol.15 Issue 1, pp.99-118

Document Type: Article

Publication Date: 3/2025

Document Language: Turkish

Document ID (Org No.): 2001342303

pISSN: 2564-7377

Issues

Authors:

Tacettin Geçkil | Talha Sarıcı | Bahadır Karabaş

Publisher:

Giresun University

Main Topics:

İnşaat Geoteknik Mühendisliği | Ulaştırma Mühendisliği

Journal:

Karadeniz Fen Bilimleri Dergisi Vol.15 Issue 1, pp.99-118

Document Type:

Article

Publication Date:

3/2025

Document Language:

Turkish

Document ID (Org No.):

2001342303

pISSN:

2564-7377