KİL ZEMİNLERİN MEKANİK DAVRANIŞINA TUZ ÇÖZELTİLERİ ETKİSİ

Öz

Kil zeminlerin kohezif karakterli olması ve su tutma davranışının non-plastik zeminlere kıyasla farklı mekanizmalarla işliyor olması nedeniyle yük altındaki mekanik davranışı da farklı mekanizmalarla açıklanmaktadır. Non-plastik zeminlerden farklı olarak killerin sıkışma, makaslama kuvvetlerine dayanma, su tutma gibi mekanik davranışında elektriksel ve moleküler kuvvetler etkindir. Kil daneleri arasındaki etkileşime etki eden kuvvetler üzerinde değişime yol açabilecek tüm dış etkiler kilin mekanik davranışna da etki etmektedir. Dolayısıyla killerin mekanik davranışları boşluk suyu kompozisyonundan etkilenmektedir. Kohezif zeminlerin su tutma davranışını etkileyen ortam sıcaklığı, pH, boşluk suyunun yalıtkanlık sabiti (dielectric constant – DC), iyon konsantrasyonu (çözünmüş tuz miktarı) gibi etkenler aynı zamanda mekanik davranışına da etki etmektedir. Yazı kapsamında kil zeminlerin mekanik davranışına etkiyen bu etkenlerden sadece boşluk suyundaki tuz yoğunluğunun etkisi incelenecektir. Bu amaçla öncelikle başucu niteliğindeki kitaplardan yola çıkarak kil-tuz etkileşimin temel mekanizması ana hatlarıyla açıklanmaya çalışılmıştır. Sonrasında yakın dönemde yapılmış güncel yayınlardaki bulgularlar, kil – kimyasal etkileşiminin temel mekanizmalarıyla irdelenerek etkileşimin genelden özele izahına çalışılmıştır.

Anahtar Kelimeler

• Su adsorpsiyonu
• Kil-kimyasal etkileşimi
• DDL
• sıkışabilirlik
• kayma dayanımı

Effect of Salt Solutions on the Mechanical Behavior of Clay Soils

Öz

The mechanical behavior of clay soils under load is also explained by different mechanisms, since they have a cohesive character and their water retention behavior works by different mechanisms compared to non-plastic soils. Unlike non-plastic soils, electrical and molecular forces are effective in the mechanical behavior of clays such as compression, resistance to shear forces, and water retention. All external effects that may cause a change on the forces acting on the interaction between clay particles also affect the mechanical behavior of the clay. The mechanical behavior of clays is affected by the pore water composition. Factors such as ambient temperature, pH, dielectric constant of pore water (dielectric constant – DC), ion concentration (amount of dissolved salt) that affect the water holding behavior of cohesive soils also affect their mechanical behavior. Within the scope of the article, only the effect of salt concentration in the pore water will be examined among these factors affecting the mechanical behavior of clay soils. For this purpose, the basic mechanism of clay-salt interaction has been tried to be explained with the main lines, starting from the books that have the quality of a bedside book. Afterwards, the findings in recent publications were examined with the basic mechanisms of the clay-chemical interaction, and the interaction was tried to be explained from general to specific.

Anahtar Kelimeler

• Water Adsorption
• Clay-Chemical Interaction
• DDL
• Compressibility
• Shear Strength

Kaynakça

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