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... Regolit malzemesi; Ay yüzeyine çarpan gök cisimlerinin oluşturduğu yapay bir tabaka olup demir, alüminyum, silikon, titanyum, oksijen, hidrojen, karbon, helyum ve azot gibi elementleri içermektedir (Taylor, 1992). Bu maddeler dikkate alındığında bilim insanları üssün kurulmasında yapısal malzeme olarak Regolitin kullanılabileceği fikrini savunmuşlardır (Lin, 1985). Bu tür projelere her ne kadar ABD öncülük etse de Rusya, Japonya ve Çin gibi başka ülkeler de benzer projeler üzerinde çalışmalar yapmaktadır. ...
... Regolit tabakası, meteorların Ay yüzeyine çarpmasıyla oluşan bir tabakadır (Taylor, 1992). Bu tabakanın içerdiği doğal maddeler, Ay'da üs inşası için gerekli birçok hammaddeyi içinde barındırmaktadır (Lin, 1985). Her ne kadar doğal kaynak açısından üs inşasında yeterli malzemenin elde edilebilirliği kanıtlanmış olsa da; bazı olumsuzlukların üs inşaatı sürecini etkileyeceği bilinen bir gerçek olarak karşımıza çıkmaktadır. ...
... Bu kapsamda üssün inşasında gerekli olan beton dökümünün Ay koşullarında yapılıp yapılamayacağına dair sorulara yanıtlar aranmaktadır. Bu düşünceyi geçerli kılan temel argüman ise betonun Ay'ın ortam koşullarından kaynaklanan sorunlara karşı çok daha dayanıklı bir malzeme olmasında yatmaktadır (Lin, 1985). Yapılan çalışmalar; Ay yüzeyinde bulunan regolit malzemesi kullanılarak beton dökümü için gerekli olan çimento bileşeninin elde edilebileceğini göstermektedir. ...
Uzay’a yapılacak olan seyahatlerin ilk basamağını Ay’a yolculuk oluşturur. Bu seyahatler genel olarak Uzay ve Ay ortamını keşfetmeye ve bilimsel çalışmalar yapmaya yönelik olsa da önümüzdeki yıllarda Ay kolonileri, Ay otelleri ve Ay habitatları gibi projelerin gerçekleştirilmesiyle seyahatlerin farklı bir boyuta ulaşacağı beklenmektedir. Ayrıca baş döndürücü hızda ilerleyen teknolojik gelişmeler ve bilgi birikimi kullanılarak uzaya yapılacak seyahatlerin sadece astronotlarla değil farklı meslek gruplarında çalışan insanları da içerecek şekilde yapılması planlanmaktadır. Bu tür projelerin hayata geçirilmesi için Ay ortamında üs inşası bilim insanları tarafından öncelikli hedef olarak belirlenmiştir. Bu amaç doğrultusunda; Ay yolculuğunun tarihçesi, Ay üssünün kurulmasındaki sebepler, alan ve malzeme seçimi, yapım sistemleri ve mimari formları hakkında bu yazıda bilgi verilecek, okuyucu Uzay’da planlanan yaşam alanı hakkında da bilgilendirilecektir.
... Lin (Lin 1987) [3] noticed the abundance of calcium oxide in regolith and raised the concept of concrete as a building material in lunar constructional activities. (Hewlett and [4] Hewlett and Young discussed the versatility of concrete and studied the chemical composition of it. ...
... Lin (Lin 1987) [3] noticed the abundance of calcium oxide in regolith and raised the concept of concrete as a building material in lunar constructional activities. (Hewlett and [4] Hewlett and Young discussed the versatility of concrete and studied the chemical composition of it. ...
The idea of “Constructions on Moon” is gaining momentum day by day given the need for Constructions on moon for conducting
research in Astronomy and for studying the possibility of survival of mankind on moon. One of the most challenging tasks for the
present day Civil Engineer is to lay an economical, safe, stable and durable structural base on the lunar surface. This is because of
lack of awareness on behavior of building materials on extra terrestrial atmosphere like lunar atmosphere. As it is uneconomical to
transport building materials from Earth, Mooncrete is worthy of consideration. The idea of Mooncrete dates back to 1985.
Mooncrete, which could be prepared using materials on lunar surface itself, proves to be a highly promising material in the extraterrestrial
constructions. The aim of this review paper is to present a summary of all the information and findings on Mooncrete as on
date. It starts out with a brief description of experiments conducted on materials used for manufacture of Mooncrete. The process of
manufacture of Mooncrete and possible difficulties that may intervene with it are outlined. The paper also presents a discussion on
various lunar regolith simulants prepared so far and predicts their behavior in lunar environment. Alternatives to water as binding
material are also suggested. The paper concludes with a brief reference to the results of current Mooncrete. The paper is expected to
create awareness in Structural Engineering community and hence encourage research in development of more economical and
practicable Mooncrete with less difficulty in manufacturing.
... Uygarlığın vazgeçilmez parçası olan bu arayış tüm zamanlarda olduğu gibi gelecekte de devam edecektir (Akman, 2003). Şu anda bir hayal gibi gelen ay da yaşam için 1980'li yıllarda Amerikan Beton Enstitüsü ve Standartlar Enstitüsü'nde (NILST ve ACI) oluşturulan bir grup tarafından çalışmalar yürütülmektedir (Lin, 1987). ...
Yapı malzemesindeki ve teknolojideki gelişim insanların yeniyi arama ve ulaşma kaygılarını hızlandırarak yapılarda malzeme çeşitlerinin kullanımını artırmıştır. Bu hızlı değişim süreci ve beraberinde yapıya getirdiği etkiler mimarların öncelikli sorunları haline gelmiştir. Bir yapının kaliteli ve uzun ömürlü olması, kullanılan yapı malzemesinin uygulanacak alana göre doğru seçilmesini de gerektirir. Yanlış yapı malzemesi seçimi, yapıda büyük zararlar ile sonuçlanabilinir. Bunun için yapı malzemelerinin fiziksel, mekaniksel ve kimyasal gibi özellikleri iyi bilinmelidir. İlk dönemlerde malzeme bilinen kapasitesi ile tasarımlara yön verirken, günümüzde ise gelişen teknoloji aracılığıyla tasarımların önemli bir bileşeni olmaktadır. Yapı malzemelerinin kullanımının mimari tasarımlar için çok önemli olmasından dolayı, yapı malzemelerindeki teknolojik gelişimin ve mimari ürün arasındaki etkileşimlerin incelenmesi bu çalışmanın çıkış noktası olmuştur. Çalışma kapsamında ülkemizde yer alan üniversitelerin mimarlık bölümlerinde, lisans düzeyinde yürütülen yapı malzemesi ile ilgili derslerin, mimarlık eğitimi sürecindeki yeri ve önemi tartışılmaktadır. Bu amaçla örneklem olarak seçilen 30 üniversitenin mimarlık bölümlerindeki ders programları incelenmiştir. Araştırma sonuçları, yapı malzemelerinin mimari tasarım alanındaki etkileri çerçevesinde değerlendirilerek tartışılmıştır. Bulgular doğrultusunda, yapı malzemesi derslerine, mimarlık eğitiminde daha fazla yer verilmesi anlaşılmış ve önerilerde bulunulmuştur.
... "Lunarcrete" may be formed from melted individual minerals CaO, SiO 2 and Al 2 O 3 at 3000 K and quenched and mixed with water. Portland lunarcrete would comprise 60-69% CaO (nominally 64% CaO which could be sourced from high calcium anorthite with up to 19% CaO), 20-24% SiO 2 (sourced from anorthite and/or orthoclase), 3-4% Al 2 O 3 (sourced from anorthite) and 2-4% Fe 2 O 3 (sourced from ilmenite) mixed with in-situ water which may be cast and cured under pressurised conditions to prevent water evaporation (Lin 1987). Concrete typically provides a compression strength of 30-40 MPa after a month of setting time. ...
We explore the limits of in situ resource utilization (ISRU) on the Moon to maximize living off the land by building lunar bases from in situ material. We adopt the philosophy of indigenous peoples who excelled in sustainability. We are interested in leveraging lunar resources to manufacture an entire lunar base in such a fashion that is fully sustainable and minimizes supplies required from Earth. A range of metals, ceramics and volatiles can be extracted from lunar minerals to support construction of a lunar base that include structure, piping and electrical distribution systems. To 3D print a lunar base, we must 3D print the load-bearing structure, electrical distribution system, water-based heating system, drinking water system, air system and orbital transport system from in situ resources. We also address the manufacture of the interior of the lunar base from local resources. The majority of systems constituting a lunar base can be manufactured from in situ resources.
... If water is readily available, concrete made from lunar material may be useful in a variety of applications (e.g. Lin, 1987). Calcium and aluminum oxides are constituents of plagioclase feldspar, which can be found everywhere on the Moon, and could be residual to processes that produce silicon from plagioclase. ...
In situ resource utilization (ISRU) on the Moon or Mars is an approach for converting indigenous resources into various products that are needed for a mission. By utilizing indigenous resources, the amount of material that must be brought from Earth is reduced, thus reducing IMLEO. ISRU has the greatest value when the ratio:
is large. Thus, in order for ISRU to have net value, it is essential that the mass of the ISRU system (i.e., the sum of the masses of the ISRU plant, the power plant to drive it, and any feedstocks brought from Earth) must be less than the mass of products produced and used by the mission. If R ≫ 1, then in comparing the IMLEO for two similar missions—one using ISRU, and the other not using ISRU—the IMLEO using ISRU will be lower. This comparison of IMLEO with and without ISRU will provide one measure of the “value” of ISRU. However, from a broader point of view, one should compare total investments (rather than IMLEO) with and without ISRU. In this regard, the investment in ISRU includes the costs of (a) prospecting to locate and validate the accessibility of indigenous resources, (b) developing and demonstrating capabilities to extract indigenous resources, (c) developing capabilities for processing indigenous resources to convert them to needed products, and (d) any ancillary requirements specifically dictated by use of ISRU (e.g., possibly a nuclear power system). The cost saving using ISRU is the investment that is eliminated by reducing IMLEO for as many launches as the ISRU system serves. If this saving is greater than the investment required, then ISRU has net value for a mission or set of related missions. If one only compares ISRU system mass with ISRU product mass, one may in some cases conclude (incorrectly) that ISRU is beneficial, when in actuality it adds to the overall mission cost. Typically, NASA plans human missions without the use of ISRU, and then considers tacking on ISRU rather late in the campaign as an embellishment. This limits the putative benefits of ISRU because all vehicles are sized without utilizing the benefit of ISRU.
... Structures that are unsuitable for Earth construction may be adequate for the reduced-gravity lunar environment [62]. Several research efforts have been directed to produce construction materials, such as cement, concrete, and sulfur-based materials, from the elements available on the Moon [90][91][92][93][94][95]. ...
How do we begin to expand our civilization to the Moon? What are the technical issues that infrastructural engineers, in particular, must address? This paper has the goal of introducing this fascinating area of structural mechanics, design, and construction. Published work of the past several decades about lunar bases is summarized. Additional emphasis is placed on issues related to regolith mechanics and robotic construction. Although many hundreds of papers have been written on these subjects, and only a few tens of these have been referred to here, it is believed that a representative view has been created. Thus summary includes environmental issues, a classification of structural types being considered for the Moon, and some possible usage of in situ resources for lunar construction. An appendix provides, in tabular form, an overview of structural types and their lunar applications and technology drivers.
... The design team Concrete Housing (Figure 5 right) is a result of ideas that developed during one of the first Alliance workshops. The initial plan of the Technical University Dresden as Alliance partner was to investigate the applicability of lunar concrete for building structures for future manned habitats on the Moon [4]. However, exchange of information during first meetings between experts from deep-sea, space and materials research led to the formation of this design team composed of representatives from space (DLR), deep-sea (AWI, GEOMAR, Jacobs University) and material science (Technical University Dresden). ...
HGF-Alliance ROBEX brings together experts from deep sea and space to develop robotic systems and technologies for the exploration of extreme environments.
... Erste Überlegungen für Beton auf dem Mond stammen aus den 1980er Jahren [23]. Vorreiter ist T. D. Lin [24], dem 1986 40 g lunarer Regolith für die Betonherstellung zur Verfügung standen, und der Druckfestigkeiten bis zu 75 N/mm² erreichte und somit die Eignung des Regolith für die Betonherstellung bewies. ...
... The key to making such an immense project affordable is to ensure the congruence of various needs for such launchers on the Moon. Prior work on Space Manufacturing looks at manufacturing in space using non-Earth based resources and energy [8][9][10][11] . The Report of the National Commission on Space, 1986, 12,13 emphasizes an economical, phased approach for space exploitation, ...
This paper considers the process for jump-starting a space-based economy. The centerpiece is a project to build the massive radiation shield for the first large-scale human habitat at one of the Lagrangian points of the Earth-Moon system. A process of synergistic development is outlined, where the markets, resources and risk reduction implications of a large economy are facilitated. Provision of clear knowledge and methods to reduce risks and calculate business models, is seen to be key to igniting sufficient public interest for this process.
... The key to making such an immense project affordable is to ensure the congruence of various needs for such launchers on the Moon. Prior work on Space Manufacturing looks at manufacturing in space using non-Earth based resources and energy [35][36][37][38]. The Report of the National Commission on Space, 1986, [39, 40] emphasizes an economical, phased approach for space exploitation, which will be technically reasonable, and will support private enterprise. ...
... Structures that are unsuitable for Earth construction may be adequate for the reduced-gravity lunar environment Chow and Lin 1989. Several research efforts have been directed to producing construction materials, such as cement, concrete, and sulfur-based materials, from the elements available on the MoonLin 1987;Agosto et al. 1988;Leonard and Johnson 1988;Namba et al. 1988a;Yong and Berger 1988;Strenski et al. 1990.The appendix to this paper provides a long list of structures that require a study not only of the materials that could be used for construction, but also of the necessary tools/equipment, methods of operation/control, and most importantly, how to construct structures with and within the lunar environment that is regolith, vacuum, 1/6 g. Because most of the construction methods developed since the beginning of mankind are adapted to fit and take advantage of terrestrial environments that is, soil characteristics, atmosphere with oxygen, and 1 g gravity, technologies that are common on Earth either will not work on the Moon or are too ...
How do we begin to expand our civilization to the Moon? What are the technical issues that infrastructural engineers, in particular, must address? This paper has the goal of introducing this fascinating area of structural mechanics, design, and construction. Published work of the past several decades about lunar bases is summarized. Additional emphasis is placed on issues related to regolith mechanics and robotic construction. Although many hundreds of papers have been written on these subjects, and only a few tens of these have been referred to here, it is believed that a representative view has been created. This summary includes environmental issues, a classification of structural types being considered for the Moon, and some possible usage of in situ resources for lunar construction. An appendix provides, in tabular form, an overview of structural types and their lunar applications and technology drivers.
The lunar regolith simulant based geopolymer was prepared, and its mechanical and structural properties under extreme temperature were investigated. Results show 7-day compressive strength of geopolymer cured at 60℃ was 58.8 MPa. After laboratory tests under extreme temperature, compressive strength of geopolymers under 120℃ and −30℃ were above 50.0 MPa and 80.0 MPa respectively. The extreme temperature resistance of geopolymers could be understood by the simulation results in terms of molecular structure stability, which reveals the stable aluminosilicate structures under lunar high temperatures and under ultra-low temperatures. After 40 cycles of thermal shocks (-196℃-25℃), compressive strength of geopolymer even increased explained by relatively dense microstructures through SEM and BET. The geopolymer based lunar concrete has demonstrated a great potential for in-situ lunar base construction.
Lunar base construction is of great importance for deep space exploration, and the establishment of lunar pavements for the movement of machinery and transportation of materials is essential to improve construction efficiency. Lunar regolith as an in-situ resource has been demonstrated to be used as raw materials to prepare geopolymers for lunar pavements. In this paper, geopolymers based on lunar regolith simulant with different concentrations of alkali activator were synthesized using the natural high-temperature of the lunar surface. Then, the durability of the resulting geopolymer under lunar high and cryogenic temperature was investigated. The flexural and compressive strength was tested, and the microstructure was characterized using Scanning Electron Microscope coupled with Energy Dispersive Spectroscopy (SEM-EDS), ²⁹Si Magic Angle Spinning-Nuclear Magnetic Resonance (²⁹Si MAS-NMR), and Mercury Intrusion Porosimetry (MIP). The results of the curing section showed that the geopolymer with 8 mol/L sodium hydroxide (NaOH) generated high strength and dense structure, and the period of 420 h–492 h of a lunar day corresponding to a temperature variation from 84.5 °C to 33.5 °C in 72 h was suitable for preparation, with 5.7 MPa and 31.2 MPa 72-h flexural and compressive strength. Three test points were selected on the lunar 30° latitude temperature curve, corresponding to before and after the cryogenic attack, and after high temperature again to investigate the durability of the geopolymer, and the degradation was found noticeable. The flexural strength decreased about 49% and 70%, and the compressive strength decreased about 15% and 18% after the cryogenic temperature and high temperature again, respectively. Microscopic observations revealed that the geopolymer structure was significantly granulated with obvious cracks and increased porosity. In addition, the formation of the zeolitic phase was unexpectedly found, leading to interfacial cracks and mechanical strength reduction of the geopolymer. This paper will be beneficial to explore the evolution of properties of lunar pavement construction materials in the lunar environment.
NASA has revealed that they plan to resume manned missions and ensure the permanent presence of people in the so-called habitats on the Moon by 2024. Moon habitats are expected to be built using local resources—it is planned to use lunar regolith as aggregate in lunar concrete. Lunar concrete design requires a new approach in terms of both the production technology and the operating conditions significantly different from the Earth. Considering that more and more often it is assumed that the water present on the Moon in the form of ice might be used to maintain the base, but also to construct the base structure, the authors decided to investigate slightly more traditional composites than the recently promoted sulfur and polymer composites thermally hardened and cured. Numerous compositions of cement “lunar micro-mortars” and “lunar mortars” were made and tested to study rheological properties, namely, the consistency, which largely depend on the morphology of the fine-grained filler, i.e., regolith. For obvious reasons, the lunar regolith simulant (LRS) was used in place of the original Moon regolith. The used LRS mapped the grain size distribution and morphology of the real lunar regolith. It was created for the purpose of studying the erosive effect of dusty regolith fractions on the moving parts of lunar landers and other mechanical equipment; therefore, it simulated well the behavior of regolith particles in relation to cement paste. The obtained results made it possible to develop preliminary compositions for “lunar mortars” (possible to apply in, e.g., 3D concrete printing) and to prepare, test, and evaluate mortar properties in comparison to traditional quartz mortars (under the conditions of the Earth laboratory).
As humanity seeks outposts on other planetary bodies such as the Moon and Mars, technology must enable safe, repeated landings and launches near habitation. The design of the Lunar Plume Alleviation Device (Lunar PAD) aims to mitigate plume impingement and abrasive regolith debris and protect the crew, lander, and surroundings. Key vent features have been designed to provide both structural support and a controlled exhaust flow, and their basic function has been analyzed via finite element analysis (FEA) and computational fluid dynamics (CFD) simulations. A subscale Lunar PAD model has been completed in October of 2020 that demonstrates its ability to be 3D printed. The Lunar PAD uses in-situ resource utilization (ISRU) methods and technologies to minimize launch mass and enable previously unimagined structures. The lessons from this work can be applied to the design, manufacturing, and testing of future full-scale landing pads. Together with future landing system developments, additive construction technologies, and plume and dust control efforts, the Lunar PAD may expand possibilities for human exploration of the solar system.
Economically viable and reliable building systems and tool sets are being sought, examined and tested for extraterrestrial infrastructure buildup. This project utilizes a unique architecture weaving the robotic building construction technology with designs for assisting rapid buildup of initial operational capability Lunar and Martian bases. The project intends to develop and test methodologies to construct certain crucial infrastructure elements in order to evaluate the merits, limitations and feasibility of adapting and using such technologies for extraterrestrial application. High priority infrastructure elements suggested by our NASA advisors to be considered include landing pads and aprons, roads, blast walls and shade walls, thermal and micrometeorite protection shields and dust-free platforms utilizing the well-known in-situ resource utilization (ISRU) strategy. Current extraterrestrial settlement buildup philosophy holds that in order to minimize the materials needed to be flown in, at great transportation costs, strategies that maximize the use of locally available resources must be adopted. Tools and heavy equipment flown as cargo from Earth are proposed to build required infrastructure to support future missions and settlements on the Moon and Mars.
Several unique systems including the Lunar Electric Rover, the unpressurized Chariot rover, the versatile light-weight crane and Tri-Athlete cargo transporter as well as the habitat module mockups and a new generation of spacesuits are undergoing coordinated tests at NASA’s D-RATS. This project intends to draw up a detailed synergetic plan to utilize these maturing systems coupled with modern robotic fabrication technologies based primarily on 3D Printing, tailored for swift and reliable Lunar and Martian
infrastructure development. This project also intends to increase astronaut safety, improve buildup performance, ameliorate dust interference and concerns, and reduce time-to-commission, all in an economic manner.
In recent years, there has been an increasing use of concrete in various fields of construction activity. Not only is concrete being used for offshore structures, nuclear power plants and barges, but there is a growing possibility that it could also be used for structures in space [1]. Additionally, the application of high strength concrete and prestressed concrete is becoming increasingly common. The study of the behaviour of structures under impulsive loading is still in its infancy. There is a need to study quantitatively the mechanical behaviour of those structures, especially in the stages prior to failure. Furthermore, performance improvement indices and concepts of performance improvement have to be determined in order to design impact resisting structures. The design codes in most countries adopt an equivalent static load in representing impact loads [2, 3]. But even though it is effective up to the maximum stresses, it would not be able to withstand the effects of excitation of the higher modes of vibration, a change in failure mode due to propagating stress waves, scabbing at the rear face of the impacted structure, etc., which are peculiar to structures under impulsive loads. Therefore, there is a necessity for a dynamic approach in designing such structures.
Recent advances in additive manufacturing methods (henceforth, 3D printing) promise enhanced local fabrication capabilities and the recent delivery of a 3D printer to the ISS is testament to such. There are 3D printing technologies that can print in plastics, metals, ceramics - this illustrates the emphasis to date on the use of 3D printers for generating structures. Although advancing on multiple fronts, the true value of 3D printing lies in its capacity to implement a universal constructor - a machine capable of fabricating any product design given an appropriate program including a copy of itself. A step in this direction is the hobbyist RepRap 3D printer that prints plastic. Although not a new concept, self-replicating machines may be physically realised by 3D printing. The focus here is on 3D printing within the context of in-situ resource utilisation (ISRU) on the Moon. All 3D printers are in essence Cartesian robots - any self-replicating 3D printer must be able to manufacture not only its structural members, but also its motors and its electronics. To date, there has been little effort to attempt to achieve this. Nevertheless, the 3D printing of actuators and associated control electronics may be considered not only essential but I submit would represent an existence proof that full self-replication is feasible. To that end, I have outlined attempts in this direction. In particular, I consider several approaches to the design of several candidate motors. I also briefly consider approaches to 3D printable electronics. Semiconductor transistor foundries would be prohibitive so vacuum tube technology offers a potentially printable approach to electronics. Simple feedback sensors are implemented using the piezoelectric properties of quartz which indeed has implications for radiofrequency applications. Beyond simple control circuitry, I have adopted neural network hardware based on analogue circuitry as the computing medium as recurrent neural networks are Turing-equivalent whilst offering high information compression in teir hidden nodes. Once these have been discussed, the full manufacturing chain from material to product must be considered. I show that such universal constructors can also 3D print spacecraft including mechanisms, control systems, power distribution avionics, computer-based avionics and communications avionics. Furthermore, the motor provides the basis of energy storage through flywheels. The first semiconductor junction solar cells were constructed from selenium and gold film offering only 1% efficiency. An alternative would be a Fresnel len-based solar furnace, from which thermoelectric conversion to generate electrical energy. I conclude that physical self-replicating machines are within reach. Copyright © 2014 by the International Astronautical Federation. All rights reserved.
Introduction: The potential for microbial life to adapt and evolve in environments beyond its planet of origin should be assessed. Little is currently known regarding the consequences when earthly microbial life is transported into space or to other planets, where the environment is very different from that of Earth. The findings from such studies will determine whether life on Earth is strictly a local planetary phenomenon or can expand its evolutionary trajectory beyond its place of origin (NASA 2003). © 2012 Springer-Verlag Berlin Heidelberg. All rights are reserved.
In the early 21st century, we are going back to the moon again. This time, not only to explore but also to stay. At this moment, concrete seems to be one of the suitable materials for constructing permanent lunar structures. Various research studies on the lunar concrete have been performed at several laboratories around the world. This is a state-of-art report of lunar concrete technologies.
The article provides an overview of findings and production processes of various mineral materials which have been developed and tested worldwide in the past with regard to the establishment of a lunar base. At the beginning, the aim and procedure of constructing a lunar base will be outlined briefly. Subsequently, the lunar environment factors and their influence on a possible construction will be described. Then the advantages and disadvantages of examined materials such as sulfur concrete, cast basalt, lunar concrete or polymer concrete, on the one hand, as well as previously investigated production processes like sintering, geothermite reaction and 3D printing, on the other hand, are presented. One promising method is the Dry-Mix/Steam-Injection method for producing a lunar concrete as a possible material which is based on cement made from lunar resources developed by T. D. Lin.
This paper investigates the compressive strength and workability of High-Performance Concrete (HPC) which yields a slump at 250 ± 20mm and a slump flow at 650 ± 50mm. From the complete stress-strain curve, it shows the peak strain will be higher while the strength increases. Two kinds of the post failure models can be distinguished. The first type (Type I) is called strain softening and the second type (Type II) is called strain snapping back. Also, it is found that the modulus of elasticity Ec decreases as the volume of cementitious paste Vp increases. On the other hand, Poisson's ratio ν increases as Vp increases.
The world's Portland cement production is the third largest emitter of anthropogenic CO2 after heating/cooling of houses and transport. If no measures are taken, 1 tonne of CO2 is emitted per tonne of clinker produced, where 60% comes from the raw meal (i.e., decomposition of limestone) and 40% from the fuel (most commonly coal). Limestone is the dominating calcium oxide source of Portland cement clinker consisting of about 60% CaO, and hence the cement plants are located near a limestone deposit as limestone constitutes about 80% of the raw meal fed to the rotating kiln for clinker production. In many areas, good limestone sources are close to depletion for several reasons (e.g., MgO should be < 5% in cement clinker), and the objective of this MSA short course contribution was to see if there are other Ca-bearing natural minerals available that can replace limestone, in particular non-carbonaceous minerals that also will lead to a reduction in CO2 emissions. The conclusion is that there is no material as widespread and abundant as limestone that can replace it on a global basis. However, there are some minerals in large deposits locally that may be utilized when new cement plants are to be localized. The most promising being wollastonite (CaSiO3) that also often occur together with limestone. The second being larnite (Ca2SiO4), but it only occurs in few places. Another mineral, anorthite (CaAl2Si2O8), is too high in alumina to play a significant role in Portland cement clinkering, and is also not of interest in calcium aluminate and calcium sulfoaluminate cements due to too high silica content. As a curiosity, gypsum may replace limestone in Portland cement clinkering, but then sulfur dioxide (SO2) is released rather than CO2, which in turn may be used for production of sulfuric acid. However, the demand of sulfuric acid is much less than the demand of Portland cement on a world basis, so this route is not viable and sulfuric acid can be obtained much cheaper from other routes (e.g., roasting sulfide ore).
Habitat in lava tubes recently discovered on the Moon and Mars, should
become a unifying concept for occupancy. The first step is to obtain a
consensus from Agencies on the validity of the concept. Afterwards, two
types of research programs should be implemented: (1) Search for lava
tubes by dedicated polar orbiters carrying low frequency radar, thermal
IR imagers, and high resolution optics in the visible. Mapping,
classification and choice of site should be achieved before 2020. (2)
Development of specific technology to begin by the end of the 2020's: -
bulldozers, elevators, and cranes for access - inflatable cylindrical
structures of large dimension for housing.
Seven potential lunar construction materials are analyzed with respect to their physical properties, processes, energy requirements, and resource efficiency. Basalt is found to be the primary construction material for initial use on a lunar base. A construction system that combines lunar regolith sintering and casting to make pressurized structures is conceptualized. The design employs 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. Advantages identified in the construction system include maximum resource utilization, relatively large habitable volumes, interior flexibility, and minimal construction equipment needs.
A variety of products made from lunar resources will be required for a lunar outpost. These products might be made by adapting existing processing techniques to the lunar environment, or by developing new techniques unique to the moon. In either case, processing techniques used on the moon will have to have a firm basis in basic principles of materials science and engineering, which can be used to understand the relationships between composition, processing, and properties of lunar-derived materials. These principles can also be used to optimize the properties of a product, once a more detailed knowledge of the lunar regolith is obtained. Using three types of ceramics (monolithic glasses, glass fibers, and glass-ceramics) produced from lunar simulants, we show that the application of materials science and engineering priciples is useful in understanding and optimizing the mechanical properties of ceramics on the moon. We also demonstrate that changes in composition and/or processing can have a significant effect on the strength of these materials.
The development of permanent lunar bases is constrained by the performance of construction materials and availability of in-situ resources. Concrete seems a suitable construction material for the lunar environment, but water, one of its major components, is an extremely scarce resource on the Moon. Cement would eventually have to be manufactured in situ through high-temperature processing of the lunar regolith. A possible alternative is to replace the binding mix of concrete (cement and water) with sulfur, the most abundant volatile on the lunar surface. Sulfur can be extracted from lunar soils by heating, demanding only moderate temperatures; it is also a by-product of oxygen extraction reactions. The economic viability and properties of sulfur-based concrete make it a suitable material for the first lunar construction activities, with a wide range of applications. The possible use of sulfur concrete imposes new constraints to the first base site selection.
A lunar factory that produces materials for the construction of large power systems on the Moon consists of mining, materials production and manufacturing components. Most of the necessary materials could be obtained by processing of the ubiquitous lunar mineral anorthite. In terms of performance (i.e., mass of systems and their power requirements), the production of elemental silicon and the recycling of reagents from materials processing are the most demanding. Loss and make-up of reagents is the dominant concern. The model derived suggests that a plant, capable of producing a 5 GW solar power station in one year, would require the emplacement of less than 1000 mt of hardware on the Moon. This suggests that a mature lunar factory could lower the cost of power in space by two to three orders of magnitude. In addition, about 80% of the factory mass would consist of its power system, suggesting that even greater economies can eventually result.
The legal regime under which the resources of the Moon can be exploited is unclear. Recent proposals indicate that states are now planning to return to the Moon. Lunar resources offer great potential, both for terrestrial applications and in the exploration of space. The possibility of resource use, in the foreseeable future, creates the need for a clarification of the legal regime in relation to the Moon. This paper explores the present legal situation, identifies shortcomings in space law, and seeks precedents in the structures that are in place to govern other global Commons. The Third United Nations Convention on the Law of the Sea is assessed as the most relevant treaty, as it regulates the use of resources located outside of the state, and it can provide an analogy for a potential regime to govern the resource utilization of the Moon. The Law of the Sea reveals further problems concerning an international agreement, for the regime highlights the discontent between developed and developing states. This draws attention to the situation concerning the Moon's legal status, for although a regime to govern lunar activities is preferable, it would likely be formed in circumstances where technologically advanced states are aware of the lunar resources which they can potentially monopolize.
This study aims to investigate the characteristics and engineering properties of the dry-mix/steam-injection method (DMSIM) which was developed to overcome difficulties involved in vacuum conditions of the lunar environment. A comparison was made to examine the differences in the hydration process, mechanical properties and the composition of hydration products between DMSIM and the normal-temperature wet-mix method (NTWMM). In DMSIM, when dry cement particles come in contact with steam, heat immediately transfers from the steam to the cement, with part of the steam being forced into the inner regions of the cement particles via the micropores. As cement particles gain activation energy and moisture condensed from steam, they undergo rapid and complete hydration. Test results showed that the optimal steaming temperature for dry-mix samples of cement and standard sand is 180–200°C and the optimal steaming scenario for 10 cm3 samples of concrete is at 200°C for 18 h. The present DMSIM has advantages of lower cement content, shorter hardening time and higher concrete strengths, as compared to NTWMM.
The moon has recently regained the interest of many of the world's space agencies. Lunar missions are the first steps in expanding manned and unmanned exploration inside our solar system. The moon represents various options; it can be used as a laboratory in low gravity, it is the closest and most accessible planetary object from the Earth, and it possesses many resources that humans could potentially exploit. This paper has two objectives: to review the current status of the knowledge of lunar environmental requirements for future lunar structures, and to attempt to classify different future lunar structures based on the current knowledge of the subject. The paper divides lunar development into three phases. The first phase is building shelters for equipment only; in the second phase, small temporary habitats will be built, and finally in the third phase, habitable lunar bases will be built with observatories, laboratories, or production plants. Initially, the main aspects of the lunar environment that will cause concerns will be lunar dust and meteoroids, and later will include effects due to the vacuum environment, lunar gravity, radiation, a rapid change of temperature, and the length of the lunar day. This paper presents a classification of technical requirements based on the current knowledge of these factors, and their importance in each of the phases of construction. It gives recommendations for future research in relation to the development of conceptual plans for lunar structures, and for the evolution of a lunar construction code to direct these structural designs. Some examples are presented along with the current status of the bibliography of the subject.
This paper summarizes the results of a qualitative investigation to identify concepts for design and construction of near-term lunar facilities. Accomplishing such construction will require an adaptation or transfer of current terrestrial technology and methods. Discussions on modularization, geosynthetic materials, aluminum materials, static load analysis, and dynamic load analysis provide illustrative examples of how terrestrial technologies can be adapted to lunar applications. These discussions provide support for the development of a phased lunar construction strategy. The initial stage of construction is characterized by small self-supporting accomodation and laboratory modules. The assembly facility stage is characterized by the construction of a large pressurized module-assembly facility. The module production stage is characterized by the fitting together of terrestrial or low earth-orbit subassemblies into completed modules within the module assembly facility. The completed modules are also tested and moved to their final location in this stage. The lunar materials stage is characterized by the construction of facilities with maximum use of lunar materials.
An energy supply system for initial manned lunar bases was studied. A 300 kWe plant was considered combining a liquid metal fast reactor with a potassium Rankine cycle. The reactor vessel is buried under ground and a regolith layer works as shielding. The settling and starting procedures on the Moon are also discussed.
How do we begin to expand our civilization to the Moon? What are the technical issues that infra-structural engineers, in particular, must address? This paper has the goal of providing an overview of this fascinating area of structural engineering. Published work of the past several decades about lunar bases is summarized. Although many hundreds of papers have been written on these subjects, and only a few tens of these have been referred to here, it is believed that a representative view has been created. The paper is organized as follows. An overview is provided of possible structural concepts, including some details on the new lunar environment that engineers must design against. This is followed by a preliminary design study of a simple surface lunar structure for manned habitation. Concluding the paper is an introduction to construction issues that face the designed.
A brief review of lunar base structural concepts is presented. The subject of risk and reliability for lunar structures is introduced and critical issues deliberated. A tensile structure is considered as an example in order to become more specific on the general introductory comments.
Human umbilical cord blood (HUCB) cells show promising advantages over bone marrow (BM) cells for a variety of diseases that require transplantation. We observed that lethally irradiated SJL/J mice given a single injection of HUCB cells survive, whereas vehicle-injected mice do not. Because survival is not due to long-term engraftment of HUCB cells, we used this HUCB/mouse model to investigate additional therapeutic benefits of HUCB cells. We investigated the mechanism by which HUCB cells accelerated endogenous hematopoiesis in mice that received either lethal (9.5 Gy) or lower-dose (8.0 Gy) radiation and then were given a single injection of HUCB mononuclear cells. Compared to irradiated control mice, the lethally irradiated, HUCB-injected group showed significant increases in peripheral white blood cell counts, red blood cell indices, and granulocyte-macrophage colony-forming units (CFU-GM) by 3 weeks. In contrast, no significant differences in these parameters were observed between control and HUCB-injected mice that received the lower dose of irradiation. Moreover, regardless of the radiation dose, only HUCB-injected mice exhibited immune responses comparable to those of age-matched normal mice. The clinical relevance of these observations was determined in long-term, culture-initiating cell assays with human BM stem cells and irradiated (gamma-) HUCB cells. CFU-GM colonies were detectable in cultures containing gamma-HUCB cells by day 15, but were undetectable in cultures without gamma-HUCB cells until day 40, suggesting a hematopoietic stimulatory role for HUCB cells. Overall, the results indicate that in addition to their use for transplantation, HUCB cells also may be used as an adjuvant therapy to enhance hematopoietic reconstitution and immunocompetence of the host. This hematopoiesis-enhancing effect represents a heretofore unrecognized function of HUCB cells.
The Hodgkin's-like Type B neoplasms which arise spontaneously in aging C57L mice (25% incidence at 21 months of age) were first reported over 40 years ago, but since then relatively little has been published about these lymphomas. Based on previous studies in SJL mice, we investigated the phenotypic and functional properties of C57L-derived lymphomas in relation to Mtv29-encoded vSAg expression by the tumor cells, and their ability to stimulate TCR Vbeta-restricted T cells. The cell surface phenotype of the C57L lymphomas indicates a B cell origin (sIg(+), MHC II(+)). These B lymphoma cells also express co-stimulatory molecules [B7-1 (CD80) and HSA (CD24)], and stimulate marked proliferation of syngeneic CD4(+) T cells. C57L B lymphoma cells exhibit Mtv-encoded mRNA by northern analysis, and also stimulate IL-2 production from Vbeta16(+) T cell hybrids, suggesting a role for Mtv 29 in this syngeneic T cell response. After transfer to syngeneic recipients, primary C57L lymphomas grow slowly, if at all. However, tumor growth is greatly accelerated by pretreatment of C57L recipients with anti-asialo GM1 antibody (but not anti-CD8 mAb), suggesting that NK cells play a major role in inhibiting lymphoma growth. If, in addition to anti-asialo GM1, the mice are also pretreated with anti-CD4 mAb, tumor growth is markedly inhibited, indicating that the lymphoma-responsive syngeneic CD4(+) T cells promote tumor growth. Therefore, although the vSAg-induced response stimulated by vSAg29 expressing lymphoma cells in syngeneic TCR Vbeta-restricted CD4(+) T cells is an important etiologic factor in this type of B cell neoplasm both in C57L and in SJL mice, the final outcome of the spontaneous neoplastic process appears strongly influenced by endogenous NK activity in aging mice.
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