Pamukkale Univ Muh Bilim Derg. Ahead of Print: PAJES-26895 | DOI: 10.5505/pajes.2023.26895

Determination of Surface Color and Solar Reflectance Index (SRI) Values of Magmatic Stones Based on Freeze-Thaw and Thermal Shock Aging, and Their Impact on Heat Island Occurance

Murat Sert¹, Rasit Altindag^2
1Department Of Mining Engineering, Afyon Kocatepe University, Afyonkarahisar
²Department Of Mining Engineering, Suleyman Demirel University, Isparta

In this study, 20 different types of magmatic-origin natural stones commonly used in the construction sector were subjected to the most prevalent aging effects in nature, namely freeze-thaw and thermal shock. Prior to and after the aging tests, the Solar Reflectance Index (SRI) values of each sample were calculated by measuring their solar light reflectance values and solar light scattering values. Additionally, the surface color measurements of each sample were taken according to the CIA color index, and the color change (∆E) values were calculated.
The primary objective of this study is to determine the changes in SRI and ΔE values of natural stones due to freeze-thaw and thermal shock aging and to examine the impact of the findings on the formation of urban heat islands.
As a result of the study, it was determined that the SRI values of the samples were higher after both aging experiments compared to before the aging experiments. When examining ΔE values, it was found that thermal shock experiments caused more significant color changes compared to freeze-thaw experiments. It has been determined that the overall increase in both SRI and ΔE values will contribute to the reduction of the urban heat island effect.

Keywords: Natural stones, freeze-thaw, thermal shock, heat island, solar reflectance index (SRI), color determination.

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Magmatik Taþlarýn Donma Çözülme ve Termal Þok Yaþlanmasýna Baðlý Olarak Yüzey Renk ve Güneþ Iþýðý Yansýtma Ýndeks (SRI) Deðerlerinin Belirlenmesi ve Isý Adasý Oluþumlarýna Etkisi

Murat Sert¹, Rasit Altindag^2
1Afyon Kocatepe Üniversitesi Maden Mühendisliði Bölümü, Afyonkarahisar
²Süleyman Demirel Üniversitesi Maden Mühendisliði Bölümü, Isparta

Bu çalýþmada yapý sektöründe sýklýkla kullanýlan 20 çeþit magmatik kökenli doðal taþ, doðada en yaygýn gerçekleþen yaþlandýrma etkilerinden donma çözülme ve termal þok etkilerine maruz býrakýlmýþtýr. Yaþlandýrma testleri öncesinde ve sonrasýnda her bir numunenin Güneþ ýþýðý yansýtma deðerleri ve güneþ ýþýðý yayýlým deðerleri ölçülerek Güneþ Iþýðý Yansýtma Ýndeks (SRI) deðerleri hesaplanmýþtýr. Ayrýca numunelerin her birinin yüzey renk deðerleri CIA renk indeksine göre ölçülmüþ ve renk deðiþim (∆E) deðerleri hesaplanmýþtýr. Çalýþmanýn temel amacý doðal taþlarýn donma çözülme ve termal þok yaþlanmalarýna baðlý olarak SRI ve ΔE deðiþimlerini belirlemek ve elde edilen bulgularýn ýsý adasý oluþumlarýna etkilerini incelemektir.
Çalýþma sonucunda numunelerin her iki yaþlandýrma deneyi sonrasýndaki SRI deðerlerinin yaþlandýrma deneyleri öncesine göre daha yüksek olduðu tespit edilmiþtir. ΔE deðerlerine bakýldýðýnda ise termal þok deneylerinin donma çözülme deneylerine göre daha fazla renk deðiþimine neden olduðu belirlenmiþtir. Hem SRI deðerlerindeki hem de ΔE deðerlerindeki genel artýþýn kentsel ýsý adasý etkisinin azalmasýna katkýda bulunacaðý belirlenmiþtir.

Anahtar Kelimeler: Doðal taþlar, donma çözünme, termal þok, ýsý adasý, güneþ ýþýðý yansýtma indeksi (SRI), renk tayini

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