Cast Basalt Research Articles

Field monitoring and modelling of sediment transport, hydraulics and hydroabrasion at Sediment Bypass Tunnels

Sediment Bypass Tunnels (SBTs) are proven to be an effective measure to reduce or even stop reservoir sedimentation by bypassing sediment laden flows around reservoir dams to the downstream river reach. They are mostly used in Switzerland, Japan, and Taiwan. However, hydraulic and sedimentological operating conditions and the resistance of the invert materials against hydroabrasive erosion affect their cost-effectiveness. Hydroabrasion is a pressing issue at SBTs, other hydraulic structures and steep bedrock rivers exposed to high sediment transport rates under supercritical flow conditions. The present study was therefore conducted to address this issue by aiming at improving knowledge on abrasion mechanics and calibrating a mechanistic saltation abrasion model enhanced by Demiral-Yüzügüllü (2021). To this end, the abrasion resistance of fourteen different invert materials installed at Solis, Pfaffensprung and Runcahez SBTs in Switzerland was quantified by annual 3D laser scanning and the hydraulic conditions and sediment transport rates were regularly monitored between 2017 and 2021. The analysis of invert scans and hydraulic conditions revealed that Prandtl’s first and second kinds of secondary currents occurring in the bends and straight sections of the SBTs, respectively, and the observed abrasion patterns were strongly interrelated. The tested potassium aluminate cement and steel fibre concretes, granite, cast basalt and steel plates had better abrasion resistance against impact of sediment-laden flows compared to other materials. Sediment mineralogical composition i.e., bulk hardness relative to the invert material properties significantly affected hydroabrasion. The enhanced abrasion prediction model was calibrated with the present data and a quasi-constant abrasion coefficient of kv = (4.8 ± 2.2) × 104 was obtained. The enhanced model is well-suited for both laboratory and field scales. The present findings will contribute to the sustainable utilization and operational safety of hydraulic structures, optimization of SBT and reservoir operations regarding bypassing efficiency and reservoir lifetime and modelling of bedrock river erosion.

A pilot study of laser-welding cast basalt blocks for lunar construction

Using sintered or melted regolith to produce masonry units is a promising option for constructing lunar base civil infrastructure. However, the ingredients needed to produce cementitious mortar are not easily available on the moon and using water-based mortars in the lunar vacuum could be problematic. This pilot study reports experimental trials using specimens cut from cast basalt tiles to investigate laser welding as an alternative method of bonding lunar masonry. In a bead-on-block study to identify the optimal laser parameters it was found that weld penetration was limited to 1.5 mm and that without preheating and annealing, cracking was unavoidable. Pairs of blocks were also butt-welded together autogenously and tested for flexural strength. With preheating and annealing in a furnace, it was possible to produce welds with tensile strengths of up to 16.5 N/mm (≈ 12.7 MPa). Even without preheating and annealing, a weld strength of 0.9 N/mm (≈ 0.6 MPa) was achieved. This might be sufficient to support masonry unit self-weight during construction to avoid the need for falsework. The pilot study demonstrated that although preventing cracking when welding cast regolith materials is challenging and weld penetration depth places an absolute limit on scalability, the technology shows sufficient promise to justify further trials. Improved results might be achieved in a vacuum with a controllable laser and if the porosity of the sintered or cast regolith parent material was optimised for weldability.

Speed of reaching the full potential heat capacity of a basalt product: Mathematical model based on experimental results

Renewable Energy Sources naturally deliver energy intermittently, causing fluctuations in energy supply. The energy is thus not provided corresponding to the actual need. With the increasing utilization of renewable energy sources, and according to energy availability, the demand for energy storage is rising. Energy storage tackles these growing problems and is therefore inevitable for a sustainable energy supply. Carnot batteries are one out of a few geographically independent storage possibilities for longer durations. A Carnot battery works in the way that electricity is stored in heat during times of overproduction and reconverted back to electricity when needed. This work focuses on the charging model of natural and cast basalt for packed bed thermal energy storage used in Carnot batteries. A mathematical model, based on experimental data of the speed of reaching the full potential heat capacity, is presented. It describes in a novel way, based on the change of heat capacity during heating and cooling, the charging and discharging behaviour of the material, independent from a possible storage layout. The model is a 4th-grade polynomial, well fitted to the data with the method of least squares.

Adhesives for the Installation of Cast Basalt Elements on Metal and Comparison of Properties when Using Different Types of Fillers

The polymeric adhesives for the installation of basalt elements on a metal base are designed primarily for environments with increased chemical and mechanical stress. They are composed of polymer resins (epoxy, polyurethane) as binders, as well as organic additives and mineral admixtures that mainly fulfill the function of filler. In all sectors of today's construction industry, maximum efficiency in the production of materials is required for sustainability purposes, which, however, must never be at the expense of the quality or the required performance. Due to these requirements, great emphasis is placed on the maximum use of secondary raw materials. Talc is used as the primary filler for polymer adhesives. Sawdust, tire rubber, and fly ash are used as secondary raw materials. The use of these in building supplies can positively affect some physical and mechanical properties of polymeric adhesives. Also, the use of secondary raw materials has the above-mentioned ecological benefit. Basic properties, such as bulk density and adhesion to both metallic and basalt elements, were monitored. The details of the cohesion of the adhesive with the bonded material, as well as the distribution of secondary raw materials in the polymer matrix, were assessed microscopically.

Chemically resistant polymeric jointing grout with environmental impact

This paper deals with the study of the chemical resistance of polymeric jointing grouts intended for the jointing of elements that are permanently stressed by an aggressive chemical environment, such as elements made of cast basalt, placed in the concrete structures of sewerages. The paper researches three types of epoxy jointing grouts designed for conditions where there is a chemically aggressive environment. The optimal amount of hazardous waste (end product and cement bypass dusts) was incorporated in the developed jointing grouts. As part of chemical resistance monitoring, changes in selected physical and mechanical properties of jointing grouts were monitored and evaluated, including microstructure monitoring after chemical stress. The scanning electron microscopy (SEM) was used for the explanation of bonding effects of the polymer matrix with the filler It was found that the use of hazardous waste is highly effective in polymeric grouts with high chemical resistance; there was no noticeable reduction in the chemical resistance of these jointing grouts compared to the reference grouts.

Chemical stability of innovative grouts for cast basalt elements

Newly developed tile grouts are intended mainly for environment with strong chemical loading. For this reason, chemical resistance was one of the key parameters observed. The grout for cast basalt tile was polymer based, in particular with epoxide binder and it utilized solidified hazardous wastes as fillers. It is well-known that epoxide binder has high resistance to solutions of inorganic substances. However, it is easily degraded by organic compounds. This was taken into consideration when assessed aggressive environments and their concentrations were selected. Examined substances were 60% solution of sulfuric acid, vapors of this acid (at concentration 96%) and 10% solution of acetic acid. After exposition to action of these aggressive substances, first of all the visual changes were assessed, i.e. change of color, formation of blisters, cracks, flaking or change of sheen. Then influence on microstructure, changes of bulk density and strengths of materials were observed.

Development of New Adhesives with Share of Secondary Raw Materials for Depositing of Non-Absorbent Facing Elements in Aggressive Environments

The main focus of this paper is research and development of new adhesive materials which will be possible to apply and withstand conditions of environments with exposure to aggressive chemical compounds. These new materials will also be required to withstand high temperatures up to 100°C. Main application of developed adhesives will be during laying of non-absorbent tiles mainly made from cast basalt. Several secondary raw materials were considered during the development of new adhesive mixtures as possible replacement of silicate filler components of new materials. The goal is to develop a new adhesive material with properties as close as possible to the highly durable non-absorbent elements used in stressed environments, mainly because the material will be also used for pointing between individual elements.

The Potentials of Improving Mineral Source Additional Values in Lampung Province – A Preliminary Study

An initial research on non-metal mineral potential was conducted for stones inLampung Province. Surveys were conducted to some districts/towns in Lampung to takesample materials. Non-metal mineral chemical composition content analysis of stoneswas conducted with X-RF method. Lampung had mineral potentials of feldspar, zeolite,kaolin, and basalt of 400,500,000 m3; 18,945,000 m3; 9,750,000 m3; 419,071,833 m3respectively. These mineral source potentials were distributed in eight districts inLampung. Processing was required to improve additional values for these mineralsources, including crushing, grinding, classifying, and concentration process.Concentration improvements were required for feldspar and kaolin minerals. Wet highintensity magnetic separator process followed by froth flotation process becamesolutions to reduce high oxide iron content. Feldspar and kaolin could be used for suchindustries of ceramic, glass, paper, and refractory. Meanwhile, the zeolite mineral fromLampung could be used for agriculture, plantation, and fishery. Basalt stone wouldhave additional values when this was processed into cast basalt, fiber, and ceramiccomposite.Keywords: feldspar, kaolin, basalt, zeolite, Lampung

Polymer based grout with specially treated hazardous waste

The present research verified the possibility of using specially treated hazardous waste (solidification product) derived from a solidification agent (fly ash from fluidized bed combustion (FA)) and hazardous waste (end-product) as a filler in polymeric grout. Hazardous waste was pre-treated by solidification technology, while within the performed research, a total of two solidification paths were verified. One of them was a dry homogenisation (TOS1) and the other technology was wet granulation of the input materials (TOS2). The use of dry homogenization solidification technology, which is economically less demanding, seems to be more advantageous. Using such specially treated filler was verified by some selected tests and the results indicated grout with a relatively high compressive strength of about 50 MPa and a flexural strength of about 20 MPa. The developed polymeric grout also showed a very good adhesion to a cast basalt, which was tested by the pull-off test and subsequently observed in detail by optical microscope.

Economic potentials of industrial rocks and minerals in the Azraq basin, NE Jordan

The Azraq basin (the Badia region in NE-Jordan) is rich in its industrial rocks and minerals. Most of the commodities are concentrated in one area, which is the Azraq depression (El-Qa’). The climatic changes (wet and dry) of Azraq closed lake contributed in the formation of industrial rocks and minerals in the El-Qa’. Basalt, pyroclastics, zeolites, diatomaceous earth, bentonite, palgorskite, porcelanite, saline brines, chalk, limestone, and gypsum are the potential industrial commodities. The basaltic rocks are of high alkalis content and good homogeneity and are of good potential use in constructions and cast basalt. The scoriaceous pyroclastic material proved to be of excellent properties for use as lightweight aggregates, cultivation purposes, and for the production of pozzolanic cement. Smectite-rich beds (bentonite) from Ein El Badia could be used as binder, absorbent, and additives for feeding farm animals. Palygorskite is potential for use in drilling mud, paint, pharmaceuticals, and as a filtering medium. The diatomaceous earth deposits are Moler type and could be used as filter aid and absorbent. Zeolites are efficient for agricultural purposes, animal waste, and wastewater treatment plants. Saline brine is exploited in the Azraq mudflat area for table salt. Porcelanite could be used as an absorbent of hazardous elements, abrasive, and filler. The softness and high purity of chalk enable its use as filler and in the lime production. The large limestone concretions are of high quality for use as a building stone. Gypsum (gypcrete) could be used after the removal of the undesired chert impurities. The Badia region is a highly potential area for future exploration and mining industry in a manner that achieves the required outcomes and minimizes impacts on ecosystems.

Review of possible mineral materials and production techniques for a building material on the moon

AbstractThis article provides an overview of the findings and production processes for the mineral materials that have been developed and tested worldwide in the past with regard to the establishment of a lunar base. Firstly, the aim of and procedure for constructing a lunar base are briefly outlined. Following that, the lunar environment factors and their influence on a possible structure are described. The paper then presents the advantages and disadvantages of the materials examined, such as sulphur concrete, cast basalt, lunar concrete or polymer concrete, on the one hand, as well as production processes investigated previously, such as sintering, geothermite reaction and 3D printing, on the other. One promising method is the dry‐mix/steam‐injection (DMSI) method for producing a lunar concrete as a possible material which was developed by T. D. Lin and is based on cement made from lunar resources.

용융주조 현무암 튜브를 이용한 생활폐기물 이송관로의 보호벽에 관한 연구

Abstract: The forces applying to an object in the transferring pipe of wa ste are analyzed and the equation of motion is established in this paper. It is shown that the equation of motion becomes the 1st order non-linear differential equation. Using its general solution, the velocity of the object in the transferring pipe o f waste can be expressed in the explicit form. Noting that the velocity of object is impact velocity to the elbow or curved part of the transferring pipe of waste, the kinetic energy of the object can be calculated and the necessary impact strength of inner wall is obtained. The velocity of object is also calculated and presented in the graphic forms wi th the condition of air velocity 30m/sec. The impact test of cast basalt tube is carrie d out by the free fall of a weight and the test results show that the impact strength of th e cast basalt tube is sufficient to apply to protecting inner wall of the transferrin g pipe of waste. Key words: Cast basalt, Automated waste collection, Drag coefficient, Transferring pipe, Final speed

Mechanical characteristics of fused cast basalt tube encased in steel pipe for protecting steel surface

Because of the various excellent characteristics of cast basalt materials, such as, anti-corrosion, anti-wearing, good hardness, high chemical stability, of which steel may not possess, the steel-basalt composite pipes are used in severe environments for compensating the defects of steel. The limit of bending moment with which steel-basalt composite pipe may safely endure was calculated and the limit curvature of the composite pipe in the safe range was presented. The application temperature of steel-basalt pipe was examined due to a different coefficient among basalt, mortar and mild steel.

Response of inherently brittle materials on higher loading rates

Generally, there are components loaded in a wide spectrum of loading rates, however most of design work is based on the data obtained using quasi-statical and uniaxial loading conditions. In the case of inherently brittle materials the situation is all the more complicated because of their brittleness. Cast basalt and soda-lime glass were the main experimental materials used in this investigation as representatives of natural based and structural brittle materials. The main aim of the paper is to investigate influence of strain rate on fracture resistance and to analyze response of the microstructure to high strain rate loading including the change of mechanical properties.

철강-현무암 복합재료 파이프의 역학적 거동에 관한 연구

Because of the various excellent characteristics of cast basalt materials. such as, anti-corrosion, anti-wearing, good hardness. high chemical stability, of which steel may not possess, the steel-basalt composite pipes are used in severe environments for compensating the defects of steel. However. without sufficient mechanical investigation prior to application. the basalt liners in steel-basalt composite pipes may be cracked and broken or the basalt liners are omitted from steel pipes in applications. In these cases, the merits of basalt materials may disappear and the basalt liners may not play their good roles as expected. Therefore, it is required that mechanical behavior of steel-basalt composite pipes and surrounding environments be fully examined before installation. The limit of bending moment with which steel-basalt composite pipe may safely endure is calculated and the limit curvature of the composite pipe in the safe range is presented in this paper. The temperature distributions and the thermal stresses are also computed and the limit difference of temperatures between inner and outer side of composite pipe is given together.

Indigenous Resource Utilization in Design of Advanced Lunar Facility

The most important consideration in the establishment and support of a permanently manned lunar base will be resource utilization. Seven potential lunar construction materials were analyzed with respect to their physical properties, processes, energy requirements, and resource efficiency. Reviewing the advantages and disadvantages of each material led to the selection of basalt as the primary construction material for initial use on a lunar base. The team conceptualized a construction system that combines lunar regolith sintering and casting to make pressurized structures. The design uses a machine that simultaneously excavates and sinters the lunar regolith to create a cylindrical hole. The hole is then enclosed with cast basalt slabs, allowing the volume to be pressurized for use as a living or work environment. Cylinder depths up to 4–6 m in the lunar mare and 10–12 m in the lunar highlands can be achieved. Advantages identified in the construction system include maximum resource utilization, relativel...