1、Designation: E2392/E2392M 10Standard Guide forDesign of Earthen Wall Building Systems1This standard is issued under the fixed designation E2392/E2392M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This standard provides guidance for earthen buildingsystems, also called earthen construction, and addresses bothtechnical requirements a
3、nd considerations for sustainable de-velopment. Earthen building systems include adobe, rammedearth, cob, cast earth, and other earthen building technologiesused as structural and non-structural wall systems.NOTE 1Other earthen building systems not specifically described inthese guidelines, as well
4、as domed, vaulted, and arched earthen structuresas are common in many areas, can also make use of these guidelines whenconsistent with successful local building traditions or engineering judg-ment.1.1.1 There are many decisions in the design and construc-tion of a building that can contribute to the
5、 maintenance ofecosystem components and functions for future generations.One such decision is the selection of products for use in thebuilding. This guide addresses sustainability issues related tothe use of earthen wall building systems.1.1.2 The considerations for sustainable development rela-tive
6、 to earthen wall building systems are categorized asfollows: materials (product feedstock), manufacturing process,operational performance (product installed), and indoor envi-ronmental quality (IEQ).1.1.3 The technical requirements for earthen building sys-tems are categorized as follows: design cri
7、teria, structural andnon-structural systems, and structural and non-structural com-ponents.1.2 Provisions of this guide do not apply to materials andproducts used in architectural cast stone (see SpecificationC1364).1.3 The values stated in either SI units or inch-pound unitsare to be regarded separ
8、ately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 This standard does not purport to address all of thesafety concerns
9、, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C1364 Specification for Architectural Cast
10、StoneD2487 Practice for Classification of Soils for EngineeringPurposes (Unified Soil Classification System)E631 Terminology of Building ConstructionsE2114 Terminology for Sustainability Relative to the Per-formance of Buildings2.2 ASCE Standards:3ANSI/ASCE 7 Minimum Design Loads for Buildings andOt
11、her Structures2.3 New Zealand Standards:4NZ97 Engineering Design of Earth Buildings, 1998NZ98 Materials and Workmanship for Earth Buildings,1998NZ99 New Zealand Standard, Earth Buildings not requiringSpecific Design, 1998 (including amendment #1, Decem-ber 1999)3. Terminology3.1 Definitions:3.1.1 Fo
12、r terms related to building construction, refer toTerminology E631.3.1.2 For terms related to sustainability relative to theperformance of buildings, refer to Terminology E2114. Someof these terms are reprinted here for ease of use.3.1.3 alternative agricultural products, nbio-based indus-trial prod
13、ucts (non-food, non-feed) manufactured from agricul-tural materials and animal by-products.3.1.4 biodegradable, adjcapable of decomposing undernatural conditions into elements found in nature.3.1.5 biodiversity, nthe variability among living organ-isms from all sources including: terrestrial, marine
14、 and other1This guide is under the jurisdiction of ASTM Committee E60 on Sustainabilityand is the direct responsibility of Subcommittee E60.01 on Buildings and Construc-tion.Current edition approved Jan. 15, 2010. Published March 2010. Originallyapproved in 2005. Last previous edition approved in 20
15、05 as E2392 05. DOI:10.1520/E2392-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American
16、 Society of Civil Engineers (ASCE), 1801 AlexanderBell Dr., Reston, VA 20191, http:/www.asce.org.4Available from Standards New Zealand, Radio New Zealand House, Level 10,155, The Terrace, Wellington 6011, http:/www.standards.co.nz.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, We
17、st Conshohocken, PA 19428-2959, United States.aquatic ecosystems and the ecological complexes of whichthey are a part; this includes diversity within species, betweenspecies and of ecosystems.3.1.6 ecosystem, na community of biological organismsand their physical environment, functioning together as
18、 aninterdependent unit within a defined area.3.1.6.1 DiscussionFor the purposes of this definition,humans, animals, plants, and microorganisms are individuallyall considered biological organisms.3.1.7 embodied energy, nthe energy used through the lifecycle of a material or product to extract, refine
19、, process,fabricate, transport, install, commission, utilize, maintain, re-move, and ultimately recycle or dispose of the substancescomprising the item.3.1.7.1 DiscussionThe total energy which a product maybe said to “contain” including all energy used in, inter alia,growing, extracting, transportin
20、g and manufacturing. The em-bodied energy of a structure or system includes the embodiedenergy of its components plus the energy used in construction.3.1.8 indoor environmental quality, IEQ, nthe conditionor state of the indoor environment.3.1.8.1 DiscussionAspects of IEQ include but are notlimited
21、to characteristics of the thermal, air, luminous andacoustic environment. Primary areas of concern in consideringthe IEQ usually relate to the health, comfort and productivityof the occupants within the indoor environment, but may alsorelate to potential damage to property, such as sensitiveequipmen
22、t or artifacts.3.1.9 renewable resource, na resource that is grown,naturally replenished, or cleansed, at a rate which exceedsdepletion of the usable supply of that resource.3.1.9.1 DiscussionArenewable resource can be exhaustedif improperly managed. However, a renewable resource canlast indefinitel
23、y with proper stewardship. Examples include:trees in forests, grasses in grasslands, and fertile soil.3.1.10 sustainability, nthe maintenance of ecosystemcomponents and functions for future generations.3.1.11 sustainable development, ndevelopment that meetsthe needs of the present without compromisi
24、ng the ability offuture generations to meet their own needs.3.1.12 toxicity, nthe property of a material, or combina-tion of materials, to adversely affect organisms.3.2 Definitions of Terms Specific to This Standard:3.2.1 adobe, n(1)(building product), unfired masonryunits made of soil, water, and
25、sometimes straw or otheradmixtures;(2)(product feedstock), the soil/straw/admixtures mix that isused to make adobe (1), (here also called earthen buildingmixtures or earthen material;(3)(building product), the earth plaster used for covering wallsor ceilings, or both;(4)(structure), the building tha
26、t is built of adobe (1), (3); and(5)(building design), an architectural style of earthen construc-tion (see also 3.2.9).3.2.1.1 DiscussionThe word itself comes from an Arabicword atob, which means muck or sticky glob or atubah “thebrick.” In many other countries, the word “adobe” is meaning-less, an
27、d it is more accurate to say “earthen-brick.” “Adobearchitecture” also has different meanings in different places.3.2.2 asphalt emulsion, na thick liquid made by combin-ing by-products of crude oil distillation with water andproprietary surfactants.3.2.3 cast earth, na construction system utilizing
28、a slurrycontaining soil plus a chemical binder such as portland cementor calcined gypsum and water, which is sprayed against orpoured into forms similar to those used for cast-in-placeconcrete; also called poured earth.3.2.3.1 DiscussionIn the sprayed system, modern shot-crete equipment is adapted t
29、o spray the wet earth mixture,which is usually stabilized earth.3.2.4 clay, ninorganic soil with particle sizes less than0.002 mm (0.00008 in.) having the characteristics of high tovery high dry strength and medium to high plasticity.3.2.4.1 DiscussionThis size definition for clay, along withthose f
30、or silt, sand and gravel, is according to Practice D2487.Other standards in the world have slightly different sizelimitations.3.2.5 cob, na construction system utilizing moist earthenmaterial stacked without formwork and lightly tamped intoplace to form monolithic walls.3.2.5.1 DiscussionReinforcing
31、 is often provided with or-ganic fibrous materials such as straw.3.2.6 earth, ngranular material derived from rock, usuallywith air voids and often with organic content (humus) (alsocalled soil).3.2.7 earth, stabilized, nearthen building mixtures towhich admixtures are added during the manufacturing
32、 processto help limit water absorption, stabilize volume, increasestrength, and increase durability (see also stabilization).3.2.8 earth, unstabilized, nearthen building mixtures thatdo not contain admixtures intended to help limit water absorp-tion, stabilize volume, increase strength, and increase
33、 durabil-ity (see also stabilization).3.2.9 earthen construction, nconstruction in which wallsand partitions are comprised primarily of earth.3.2.9.1 DiscussionRoofs and other framing may bewholly or partly of wood or other materials. Common earthenconstruction systems go by many names, which someti
34、mesconnote minor variations. Some of those names are:adobe,ormud brick, earthen brick, banco, butabu, brique de terrecast earth, or poured earth, earthcrete, sprayed earthcob, or zabur, puddled mud, puddled earthextruded earth blockpressed brick,orcompressed earth brick/block (CEB)rammed earth,orpis
35、, tapialsod, or turf, fale and divettire houses, also earth bags, earth tubeswattle and daub, or quincha, jacal, barjareque, nyumba yo mata3.2.10 energy effcient, adjrefers to a product that requiresless energy to manufacture or uses less energy when operatingin comparison with a benchmark for energ
36、y use, or both.3.2.10.1 DiscussionFor example, the product may meet arecognized benchmark, such as the EPAs Energy Star Programstandards.3.2.11 gravel, ninorganic soil with particle sizes greaterthan 4.75 mm (0.187 in.).E2392/E2392M 1023.2.12 horizon, ndistinctive layer of in situ soil havinguniform
37、 qualities of color, texture, organic material, andobliteration of original rock material.3.2.12.1 DiscussionIn World Reference Base for SoilResources, by the Food and Agriculture Organization of theUnited Nations, seven master horizons are recognized H, O,A, E, B, C, and R.3.2.13 loam, nsoil with a
38、 high percentage of organicmaterial, particles are predominately silt size but range fromclay size to sand size.3.2.13.1 DiscussionLoams are usually good agriculturalsoils due to their nutritional organic content and their ability tohold water. Loams should be avoided in earthen construction,as the
39、organic content is subject to biological decay andvolume change. Note that the word “ loam” derives from theGerman “lehm.” In Europe, “loam” and “lehm” usually havean opposite meaning; that is, they connote earth with a verylow organic content, ideal for building but not for agriculture.3.2.14 mater
40、ial (product feedstock), nrefers to the sub-stances that are required for the manufacture or fabrication, orboth, of a building product.3.2.14.1 DiscussionMaterial resources include raw mate-rials and recycled content materials.3.2.15 moisture wickingthe capillary uptake of waterfrom foundation soil
41、 or precipitation.3.2.15.1 DiscussionMoisture wicking can result in satu-ration of adobe with an accompanying decrease in strength anddurability.3.2.16 operational performance, nrefers to the function-ality of a product during its service life.3.2.16.1 DiscussionSpecific measures of operational per-
42、formance will vary depending upon the product. Aspects ofoperational performance include: structural strength, durability,energy efficiency, and water efficiency.3.2.17 poured earth , nsee cast earth.3.2.18 pressed block, na block (or brick, or the construc-tion system using those blocks) that consi
43、sts of earthenmaterials formed in a block mold by the mechanical compac-tion of lightly moistened earth into a dense mass (also calledcompressed earth block, CEB).3.2.19 rammed earth, na construction system that con-sists of walls made from moist, sandy soil, or chemicallystabilized soil, which is t
44、amped into forms (mechanicallystabilized).3.2.20 sand, ninorganic soil with particle sizes rangingfrom 0.75 to 4.75 mm (0.03 to 0.19 in.).3.2.21 silt, ninorganic soil with particle sizes rangingfrom 0.002 to 0.75 mm (0.00008 to 0.03 in.) having thecharacteristics of low dry strength, low plasticity,
45、 and littledilatancy.3.2.22 soil, nsee earth,3.2.23 stabilization, nmodification of soils to limit waterabsorption, stabilize volume, increase strength, and increasedurability, or some combination of these.3.2.23.1 DiscussionFor the purposes of this guide, refer-ence to “stabilization” or “stabilize
46、d” means chemical stabili-zation or chemically stabilized. Chemical stabilization isachieved by the intermixture of cement, lime, gypsum, asphaltemulsion, or other materials with the soil before emplacement,and curing as appropriate for the stabilizer and chemicalreaction. Mechanical stabilization i
47、s achieved by compactingor compressing a plastic earth mixture, or containing earth inpermanent forms such as bags.3.2.24 straw, nan agricultural waste product that is thedry stems of cereal grains, or sometimes native grasses, afterthe seed heads have been removed.3.2.25 straw-clay, na construction
48、 system that consists ofclay slip mixed with straw, of which straw makes up a highpercentage by volume.3.2.25.1 DiscussionOther fibers such as wood shavings orpaper are sometimes used. This system is well suited formanufacturing blocks and in situ insulating wall panels.4. Summary of Practice4.1 Thi
49、s guide identifies the principles of sustainabilityassociated with earthen building systems. Additionally, itoutlines technical issues associated with earthen buildingsystems, identifying those that are similar to construction thatis commonly used in the marketplace.4.2 This guide is intended for use in framing decisions forindividual projects.4.3 This guide is intended for use in development ofstandards and building codes for earthen building systems.5. Significance and Use5.1 Historical OverviewEarthen building systems h
