SUGGESTING CONVERSION FACTOR COEFFICIENTS for ESTIMATING DIFFERENT TYPES of SCHMIDT HAMMER REBOUND HARDNESS VALUES

Abstract

Mechanical properties of rocks such as uniaxial compressive strength, tensile strength, shear strength are the properties that determine their behavior under load. These properties of rocks are often determined by difficult, complex, time-consuming and expensive test methods. Therefore, instead of determining these properties directly, these properties can be estimated indirectly by using relatively inexpensive, fast and easily applicable methods. The surface hardness parameter of Schmidt hammer rebound hardness is fast, inexpensive, and easy to apply to determine the hardness of rocks and concrete. It is also used to indirectly determine the mechanical properties of rocks. It is seen that two different types of hammers (N-type and L-type) with different impact energies are commonly used in the literature. In this study the correlations between the surface hardness of different rocks obtained using N-type and L-type Schmidt hammers were analyzed. For this purpose, data were compiled from studies in the literature, which included both N-type and L-type Schmidt hammer rebound hardness of different rock types, and the collected data were analyzed statistically. Coefficients have been proposed for the conversion of N-type and L-type Schmidt hammer rebound hardness to each other.

Keywords

• Schmidt Hammer Rebound Number
• Conversion Factor Coefficient
• Rock

KAYALARIN FARKLI TİP SCHMİDT ÇEKİCİ GERİ TEPME SERTLİK DEĞERLERİNİN TAHMİNİ İÇİN DÖNÜŞÜM KATSAYISI ÖNERİLMESİ

Abstract

Kayaların tek eksenli basınç dayanımı, çekme dayanımı, makaslama dayanımı gibi mekanik özellikleri yük altındaki davranışlarını belirleyen özellikleridir. Kayaların bu özelliklerini çoğu zaman zor, karmaşık, zaman alıcı, pahalı deney yöntemleri ile belirlenmektedir. Bu yüzden bu özellikleri doğrudan belirlemek yerine nispeten ucuz, hızlı ve kolay uygulanabilir yöntemlerle belirlenen kaya özellikleri ile bu özellikler dolaylı olarak tahmin edilebilir. Schmidt çekici geri sıçrama sertliği de kayaların ve betonun yüzey sertliğini tespit etmek için kullanılan bir yöntemdir. Schmidt çekici testi hızlı, görece ucuz ve kolay uygulanabilirdir. Aynı zamanda kayaların mekanik özelliklerinin dolaylı olarak belirlenmesinde kullanılır. Yöntemin hem arazide hem laboratuvarda uygulanabiliyor olması yöntemin diğer avantajlı yönüdür. Literatürde yaygın olarak kullanılan farklı darbe enerjilerine sahip iki farklı çekiç tipinin (N-tipi ve L-tipi) kullanıldığı görülmektedir. Bu çalışma kapsamında N-tipi ve L-tipi Schmidt çekici kullanılarak elde edilmiş sertlik değerlerinin birbiri ile arasındaki ilişkiler incelenmiştir. Bunun için literatürde farklı kaya türlerine ait hem N-tipi hem de L-tipi Schmidt çekici geri sıçrama sertliklerinin yer aldığı çalışmalardan veriler derlenmiş, derlenen veriler istatistiksel olarak incelenmiştir. N-tipi ve L-tipi Schmidt çekici geri sıçrama sertliklerinin birbirine dönüşümü için katsayılar önerilmiştir.

Keywords

• Schmidt Çekici Geri Tepme Sertliği
• Dönüşüm Katsayısı
• Kaya

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