ABSTRACT
The data presented in the article consist of petrographic types and grain shape parameters of beach gravels collected along the Pogorzelica-Dziwnów coast section (363.0 to 391.4 km of the coastline), southern Baltic Sea, Poland. Representative gravels with the diameter of 2-5 cm were sampled at 0.25 km intervals, in the middle part of the beach. The contribution of mechanically high resistant crystalline components (igneous and metamorphic rocks: granites and gneisses) and low resistant (sedimentary rocks: limestones, sandstones, and shales) has been presented. The Cailleaux and Zingg grain shape parameters were estimated taking laboratory measurements (3D-axis dimensions, flatness/roundness indices). The calculations have been provided based on the gravels weight and quantity. The obtained grain shape parameters depend on factors such as resistance to mechanical destruction or increased chemical weathering, being evidenced by several indices, such as the proportions between discoidal and ellipsoidal grains, or amount of spindle-shaped gravels. The calculated indices may serve as potential indicators of coastal lithodynamics, including intensity of sediment redeposition or mechanical reworking of the beach.
ABSTRACT
Using the waste materials in the production of the building materials limits the storage of the wastes, burdensome for the environment and landscape, and makes possible to manufacture the materials and products with the use of the less volume of the raw materials. Cement concretes and mortars as the basic building materials offer the broad prospects of utilization of the recyclable or waste materials. The wastes from the iron ore processing are the solid wastes resulting from the process of enrichment of the ore concentrate. The paper presents the results of testing three mortars, in which a part of fine aggregate was replaced with the iron oxide concentrate (IOC) resulting from such a process. IOC has been used as a substitute of 10%, 20% and 30% (by mass) of the fine aggregate. The effect of the concentrate on the mechanical performance of the mortars at the high temperature (up to 600 °C) was also investigated. The IOC is a neutral material, not affecting chemically the process of cement hydration. The addition of IOC slightly improves the strength of the cement mortars (by 5% to 10%). In the case of the larger amount (20-30%) of the addition, the use of superplasticizer is necessary. The IOC significantly improves the high temperature resistance of the cement mortars (300 °C). The cement mortars containing 30% of the IOC addition keep 80% of the initial flexural and compressive strength when exposed to the temperature 450 °C.
