Many variations of natural stones like basalt, marble, limestone, sandstone, quartzite, travertine, slate, gneiss, laterite, and granite can be used as a beneficial construction material. The stones which are used for building construction projects should have strength, durability, toughness, also they should be clean out of weathered soft patches of material, cracks, and some other defects that can the decrease the strength and durability. Stones used for construction projects are often obtained by quarrying and mining out of solid massive rocks.
Stones as Construction Materials
The need for development in innovation of materials is beneficial in every stage of societal improvements, it results in development of countries. One of such material with abundant sources is basalt. Basalt has captured the attention of societies from the 20th century onwards; it can be used in different forms such as fibre, rod, grid and laminates. Due to its properties such as high modulus of elasticity, high elastic strength, corrosion resistance, high-temperature resistance, extended operating temperature range and ease of handling; basalt fibres has attracted interests as a construction material. With a rich historical background and different subcategories; basalt is used in the construction industries from fibre development and different chemical and mechanical fibre properties to its applications in the field projects. There are studies that can show the possible applications use of basalt towards sustainable construction.
Based on the properties of each variation of stones, they can have different types of construction applications. For example, some types such as basalt and granite have superior characteristics like high compressive strength and durability so they are mostly used in major construction works. However, there are stones that because of their characteristics like gneiss with low compressive strength or presence of deleterious materials in their constituents, can only make them suitable and fit for minor construction process. Thus stones can also be used as building materials and some other decorative purposes to.
Basalt, a Construction Material
Basalt is one of the most important and common extrusive volcanic rocks. Based on how rapid cooling of lava at the surface of earth is, it usually is in grey to black colors. Basalt is an igneous rock and it is mainly composed out of plagioclase and pyroxene minerals, similarly to gabbro. the difference between them is that basalt has a fine-grained texture while gabbro is a coarse-grained rock. Basalt can form as an extrusive rock from lava flow or it can form in small intrusive bodies like a thin sill. Most of basalts specimens are compact, fine-grained, and glassy. the holes left by gas bubbles in its texture, can give it a coarsely porous look.
The compression strength of basalt has a range of 200MPa to 350Mpa. Its weight is between 18KN/m3 and 29KN/m3. Basalt is impervious to moisture so has a good resistance facing weather. It is tough and very difficult to saw in fine shapes. Based on its formation process, its color changes from different shades of dark gray to black.
Basalt Formation Processes
One of the important facts about basalt is that, it is the most abundant bedrock on earth which means that it covers the most of the surface of earth. For instance, ocean basins most areas are underlain by basalt. Earth’s basalt can mostly be found on three environments, In order of oceanic divergent boundaries, oceanic hotspots, and mantle plumes or hotspots under the continents. Most of the basalt on Earth is built on the mid-ocean ridge system at divergent plate boundaries. in this process, convection currents will deliver hot rocks out of deep in the mantle. This hot rock melts and pulls apart at the divergent boundary then molten rocks erupt in to the sea floor. These eruptions often produce basalt rocks with shapes like pillow. The repeated fissure eruptions happen, mostly in the active mid-ocean ridges. by being under the deep waters, most of these activities are unnoticed and anything made out of this process like ash, steam or gas is absorbed by the water and cannot reach the sea level. the only notice able sign for humans is earthquakes. except for the Iceland because it is a location where a mid-ocean ridge is sea level and visible to the naked eye; so people can see the volcanic activities directly. Second place where great amounts of basalt are produced is on the oceanic hotspots. In These locations, a small plume of hot rock rises up out of the mantle from a hotspot on Earth’s core. This process starts with a great eruption on the ocean floor. If the process of eruption happens repeatedly, these hotspots can make the volcanic cone larger enough to build an island. For instance, the Hawaiian Islands have been built from this process above one of the oceanic hotspots. The last basalt-forming environment is in a continental environment. On this process a mantle hotspot surrenders enormous amounts of basaltic lava out of the continental crust on to Earth’s surface, Vents or fissures can form these eruptions. These eruptions can repeatedly happen for millions of years and produce layers of basalt stacked in a vertical formation.
basalt stone uses in construction/Weathering
Basalt is rich with iron and magnesium and it has a main composition of olivine, pyroxene, and plagioclase. In Comparison to other rocks on earth, basalts can weather rapidly. Due to the fact that the iron-rich typed of minerals oxidize fast in water and air. Because of the rust, it leaves a brownish to red color stain on the rock. Chemical weathering can quickly release water-soluble cations such as calcium, sodium and magnesium, which gives the basaltic areas a great buffer capacity upon the acidification. We should note that these eruptions of basalt can release of large amount of quantities of CO2 into the atmosphere from volcanic gases.
Basalt on Moon and Mars
Another strange fact about basalt is that a large area of the moon is covered by basalt. “Maria Ghamari” is the name given to these areas on the moon. One of the factors determining the age of a lunar Maria is the density of its impact craters to the ground. Newer basalt streams will have smaller openings.
Olympus Mons is the name of a volcano on Mars that, like other volcanoes on Mars, has basaltic lava flows. Olympus Mons is also the highest mountain on Mars and the largest volcano in the solar system.
ٍIn the end,basalt stone uses in construction, basalt stone has medium to fine grained and compact structure which makes it a common use in road construction projects, as aggregate in concrete productions, rubble masonry works for bridge piers, river walls, and dams.
Basalt stone from Unikastone is available in several colors. Choose from among over a dozen finishes for your stone project. Unilastone can have hand and machine finishes applied economically to basalt stone at the factory and then shipped to your job site ready to install.
