Effect of heat capacity and physical behavior on strength and durability of shale, as building material

Increasing use of rock materials like shale in building, roofing, embankment filling, brick manufacturing, and in other civil structure application makes it an important rock to consider in construction engineering. Knowledge of thermal and physical properties of shale as building material is required to predict the rock\u27s strength and permanence against weathering. Inconsistent heat capacity of anisotropic rock can result in differential heat flow. This tendency can expand the building materials leading to reduction in strength and initiate disintegration. Authors have studied various thermo-physical properties of anisotropic shale from Tennessee, which is commonly used as building stones and bricks. Experiment was designed to measure the basic thermal property, \u27heat capacity\u27 of shale. Series of laboratory tests including durability, strength, specific gravity, moisture content, and porosity were conducted to determine the physical and mechanical behavior of the samples. Results indicated that properties like porosity, strength and heat capacity varied significantly within samples, where as specific gravity and moisture content yielded steady values. Multivariate regression analysis was performed to evaluate possible correlations among the tested properties. Strong positive relationship was evident between heat capacity, and porosity. Heat capacity and Unconfined Compressive Strength of shale were inversely related. This study emphasized that physical and thermal properties of shale are directly linked with strength and durability of the rock mass

Surface runoff and carbonates-based definition of protection zones for Egirdir Lake in western Turkey

Freshwater of Isparta and Egirdir is supplied from the Egirdir Lake, which is the second largest freshwater lake of the Lakes District in Western Turkey. The Egirdir Lake has been studied within the framework of the Basin Protection Plan Special Provisions of the Egirdir Lake. The impact of runoff is taken into account in determining protection zones of the surface water reservoirs in Turkey. An approach that emphasizes the impact of groundwater flow in addition to the surface runoff has been adopted in this study. Water in Lake Egirdir is often classified as the Class II water according to terrestrial water resources quality criteria in Water Pollution Control Regulation of Turkey. The geological and hydrogeological studies reveal a significant amount of groundwater recharge into the Egirdir Lake through carbonate rocks and alluvial deposits outcropping in the basin, which is why Egirdir Lake still has a less contaminated water quality in spite of heavy pollutants. For this purpose, groundwater flow is prominently used in defining protection zones and surface runoff as well. The inner protection zone, which is defined as the 50-day travel time, and the outer protection zone, defined as the 400-day travel time, were estimated by infiltrometer and pumping tests in alluvium. Pumping tests results were used for the determination of hydraulic conductivities and groundwater levels for the determination of hydraulic gradients. Protection zones in karstic areas are based on the vulnerability map and large karstic springs

On the technical properties of the Carovigno stone from Apulia (Italy): physical characterization and decay effects by means of experimental ageing tests

Apulia (southern Italy) is typified by widespread outcrops of rocks exploited in the last centuries in historical architectures and religious constructions, as building and decorative stone. Today, as in the past, these stones represent an important source for region economy and prestige, due to their uses for modern works, restoration of local medieval churches and also exporting abroad. Among these, a noteworthy and still poorly known material is the Carovigno stone. In this paper, firstly an overall view on the, mineralogical and petrophysical features of the stone was reached through a multianalytical approach based on several investigation procedures and techniques, including ultrasonic test, X-ray diffractometry, scanning electron microscopy, optical microscopy, mercury intrusion porosimetry. In order to simulate decay phenomena, the Carovigno stone samples were processed to three different ageing tests: cycles of thermal treatments at different high temperatures, cycles of heatingâcooling and cycles of exposure to decahydrate sodium sulphate and sodium chloride saline solutions. During and after each ageing processes, mineralogical transformations and petrophysical changes were evaluated. Results suggested that the Carovigno stone is a fine-grained calcarenite, pure or nearly pure, characterized by high porosity and, consequently, very notable thermal stress resistance. Conversely, the type and amount of porosity causes stone predisposition to salt crystallization decay