Kum Zeminlerdeki Kazıklı Radye Temellerin Optimum Kazık Aralığının Deneysel Olarak İncelenmesi

Abstract

Kazıklı temeller, yapı yüklerinin yüzeysel temellerle güvenle taşıtılamadığı durumlarda kullanılmaktadır. Kazıklı radye temeller, kazık ve radyenin yük taşıma kapasitelerini birleştiren bir temel sistemi olması sebebiyle son yıllarda ön plana çıkmıştır. Bu sebeple söz konusu temel sistemlerinin güvenilir ve ekonomik tasarımı için kapsamlı teorik ve deneysel çalışmalar yapılmaktadır. Bu çalışmada, kum zemin içerisinde yer alan kazıklı radye temellerin tasarım parametrelerinin etkileri (kazıklar arası mesafe, kazık çapı, kazık uzunluğu ve rölatif sıkılık, vb.) deneysel olarak araştırılmıştır. Laboratuvar deneylerinde, çapı 20 ve 30 mm, uzunluğu 200 ve 300 mm olan model kompozit (çelik ve beton) kazıklar kullanılmıştır. Plan boyutları 160x160 mm, 240x240 mm ve kalınlığı 6 mm olan model radyeler, çelik plakadan imal edilmiştir. Farklı tasarım parametrelerine sahip model kazıklı radye temeller test edilmiştir. Deney sonuçlarından, kazıklı radye temellerde kazıklar arası mesafe arttıkça taşıma gücünün bir sınır değer kadar arttığı ve kazıklar arası optimum mesafenin 4D olduğu belirlenmiştir. Temel mühendisliği uygulamalarında kullanılmak üzere tasarım parametreleri önerilmiştir.

Keywords

• Kazıklı radye temel
• Kazık tasarım parametreleri
• Optimum kazık aralığı

Experimental Investigation of Optimum Piles Spacing for Piled Raft Foundation in Sandy Soils

Abstract

Piled foundations are used in the cases where the structural loads cannot be carried safely with the shallow foundations. Piled raft foundation has become a prominent foundation system in recent years due to that it combines load bearing capacities of piles and raft. Therefore, comprehensive analytical and experimental studies have been carried out for reliable and economic design of piled raft foundations. In this study, the effects of design parameters of piled raft foundations in sand (pile spacing, pile diameter, pile length and relative density etc.) have been investigated experimentally. In the laboratory tests, model composite (steel and concrete) piles with diameters of 20, 30 mm and lengths of 200, 300 mm were used.The raft was made of steel plate with plan dimensions of 160x160, 240x240 mm and a thickness of 6 mm. The model piled raft foundations with different design parameters were tested. From the tests results, as the pile spacing getting larger, the bearing capacities of the model pile raft foundation increased up to a limit value and the optimum distance between the piles was determined to be 4D. Some design parameters are suggested for use in foundation engineering applications.

Keywords

• Piled raft foundation
• Design parameters of pile
• Optimum pile spacing

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