BS 8601-2013 Specification for subsoil and requirements for use《地基规范和使用要求》.pdf

1、BSI Standards PublicationBS 8601:2013Specification for subsoil andrequirements for usePublishing and copyright informationThe BSI copyright notice displayed in this document indicates when the documentwas last issued. The British Standards Institution 2013Published by BSI Standards Limited 2013ISBN

2、978 0 580 69112 6ICS 13.080.01The following BSI references relate to the work on this document:Committee reference AW/20Draft for comment 13/30209661 DCPublication historyFirst published December 2013Amendments issued since publicationDate Text affectedBS 8601:2013 BRITISH STANDARDContentsForeword i

3、iIntroduction 11 Scope 12 Normative references 13 Terms and definitions 24 Subsoil classification and characteristics 35 Sampling of subsoil 76 Stripping, handling and trafficking of subsoil 77 Information to be provided by the supplier to the purchaser 11AnnexesAnnex A (normative) Method of sample

4、reduction and preparation 13Annex B (normative) Determination of mass loss on ignition 13Annex C (normative) Determination of mineral carbonate content of soil (ascalcium carbonate) 15Annex D (normative) Extraction of the exchangeable cations in soil fordetermining exchangeable sodium percentage 17A

5、nnex E (normative) Calculation of exchangeable sodium percentage of soil 18Annex F (normative) Determination of the specific electrical conductivity of acalcium sulfate extract of soil 19Annex G (normative) Method for determining other contaminants 21Annex H (normative) Importance of soil electrical

6、 conductivity, soil salinity andexchangeable sodium percentage (ESP) 22Bibliography 23List of figuresFigure1Textural classification (limiting percentages of sand, silt and clay sizedparticles for the mineral texture class) and the area of textures that areacceptable within BS 8601:2013 6Figure 2 Pre

7、ferred method of stripping subsoil 8Figure 3 Preferred method of stockpiling dry non-plastic subsoil 9Figure 4 The loose-tipping method for placing subsoil and topsoil, includingsubstrate loosening 10List of tablesTable 1 Subsoil characteristics 5Summary of pagesThis document comprises a front cover

8、, an inside front cover, pages i to ii,pages 1 to 24, an inside back cover and a back cover.BRITISH STANDARD BS 8601:2013 The British Standards Institution 2013 iForewordPublishing informationThis British Standard is published by BSI Standards Limited, under licence fromThe British Standards Institu

9、tion, and came into effect on 31 December 2013. Itwas prepared by Technical Committee AW/20, Topsoil, other growing media andturf. A list of organizations represented on this committee can be obtained onrequest to its secretary.Relationship with other publicationsThis British Standard is intended to

10、 complement BS 3882 which specifies topsoil.Information about this documentTest laboratory accreditation. Users of this British Standard are advised toconsider the desirability of selecting test laboratories that are accredited toBS EN ISO/IEC 17025 by a national or international accreditation body.

11、Use of this documentIt has been assumed in the preparation of this British Standard that theexecution of its provisions will be entrusted to appropriately qualified andexperienced people, for whose use it has been produced.Hazard warningsWARNING. This British Standard calls for the use of substances

12、 and/orprocedures that can be injurious to health if adequate precautions are nottaken. It refers only to technical suitability and does not absolve the userfrom legal obligations relating to health and safety at any stage.Presentational conventionsThe provisions of this standard are presented in ro

13、man (i.e. upright) type. Itsrequirements are expressed in sentences in which the principal auxiliary verb is“shall”.Commentary, explanation and general informative material is presented insmaller italic type, and does not constitute a normative element.Requirements in this standard are drafted in ac

14、cordance with the Rules for thestructure and drafting of UK standards, subclause J.1.1, which states,“Requirements should be expressed using wording such as: When tested asdescribed in Annex A, the product shall .”. This means that only those productsthat are capable of passing the specified test wi

15、ll be deemed to conform to thisstandard.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legalobligations.In par

16、ticular, attention is drawn to the Environmental Protection Act 1990 1.BRITISH STANDARDBS 8601:2013ii The British Standards Institution 2013IntroductionThe subsoil is an essential component of most soil profiles. Only soil that isshallow over rock lacks a subsoil layer. Subsoil provides storage of m

17、oisture,transmits rainfall to deeper layers or watercourses and enables deep rooting bytrees, shrubs, grasses and other plants. It controls the waterlogging of surfacelayers, helps vegetation and crops to withstand summer droughts and providesanchorage for trees.Subsoil plays an important role in re

18、ducing the amount and speed of surfacewater runoff, reduces the risk of erosion and flooding and consequently is anintegral part of sustainable drainage systems.Subsoil can be both naturally-occurring and manufactured. Naturally-occurringsubsoil is the product of dynamic chemical, physical and (to a

19、 lesser extent)biological processes acting on weathered mineral matter. Subsoil can bemanufactured by combining mineral ingredients to provide a medium that candevelop properties similar to naturally-occurring subsoil.Soil is a dynamic and fragile material, which when managed appropriately fulfilsit

20、s function, but is easily damaged by mishandling. It is important that soil islifted, transported, stored and spread carefully. Damage during handling canresult in a rapid deterioration in the functions soil provides.NOTE 1 Transporting soil involves mechanical handling, i.e. excavation, loading,tra

21、nsport and distribution on site. Not all naturally-occurring soils would survive suchhandling and retain the ability to develop into an acceptable soil in a reasonabletime at the new site, even though in their undisturbed, naturally-occurring conditionthey might be very productive and capable of sus

22、taining plant growth over longperiods of time. For example, clay textured soil could be very productive in situ butits structure might suffer damage during stripping (or other handling activities) thatcould only be reversed by years of careful management.NOTE 2 In the context of soil profile constru

23、ction, the subsoil is also an importantmedium for root growth since it provides reserves of water and available plantnutrients and mechanical anchorage.1 ScopeThis British Standard specifies requirements for the classification, compositionand use of subsoils that are moved or traded for creating soi

24、l profiles intendedto support plant growth. The standard is not applicable to topsoil, or to subsoilthat is to remain in situ. It is not intended to preclude the use of subsoil that isalready on site and suitable for its intended purpose. This standard specifiesrequirements for multipurpose subsoil,

25、 which is fit for the majority of needs,and also specific purpose subsoils that are acidic or calcareous, for specialist usewhere acidic or calcareous soil profiles are required. It also specifiesrequirements for sampling and analysis of subsoil.2 Normative referencesThe following documents, in whol

26、e or in part, are normatively referenced in thisdocument and are indispensable for its application. For dated references, onlythe edition cited applies. For undated references, the latest edition of thereferenced document (including any amendments) applies.BS 7755-5.6:1999 (ISO 11272:1998), Soil qua

27、lity Part 5: Physical methods Section 5.6: Determination of dry bulk densityBS EN 12579:2000, Soil improvers and growing media SamplingBRITISH STANDARD BS 8601:2013 The British Standards Institution 2013 1BS EN ISO 3696:1995, Water for analytical laboratory use Specification and testmethodsBS ISO 10

28、390:2005, Soil quality Determination of pHBS ISO 11277:2009, Soil quality Determination of particle size distribution inmineral soil material Method by sieving and sedimentationBS ISO 16729:2013, Soil quality Digestion of nitric acid soluble fractions ofelements3 Terms and definitionsFor the purpose

29、s of this British Standard, the following terms and definitionsapply.3.1 topsoiltop layer of soil, darker in colour and with more organic matter than the layerbelow (subsoil), or manufactured soil with similar properties3.2 subsoilsoil layer extending between the topsoil and the little weathered par

30、entmaterial below, or material that functions in the same way in a constructed soilprofile and on to which topsoil can be spreadNOTE Usually subsoil has a lower concentration of organic matter and availableplant nutrients than topsoil.3.3 soil textureproportion by mass of sand, silt and clay sized p

31、articles in the mineral fraction ofthe 2mm401kgsampleminimum20mm2075mm0SoilpH(measuredinwater)5.5to8.53.5to5.57.5to8.5BSISO10390:2005Carbonate%m/m1AnnexCExchangeablesodiumpercentage(ESP)%7.0Zn(Nitricacidextractable)2mm10 mm in 24 h) occurs during soilstripping operations, work should be suspended an

32、d not restarted until the groundhas had at least one dry day or until a suitable moisture content has been reached.A soil can be considered to have a suitable moisture content for stripping andhandling if the whole thickness of the subsoil layer being stripped and/or handled isat a moisture content

33、below the plastic limit as determined in accordance withBS 1377-2:1990 (incorporating Amendment No. 1).Machinery should be selected and routed to minimize soil compaction.6.1 GeneralSubsoil shall not be stripped, handled or trafficked: in a waterlogged condition; when the ground is frozen or covered

34、 by snow; or when there are pools of water on the ground surface.To minimize risks of damage to the soil structure, whenever possible, soil shallbe moved directly from where it is stripped or manufactured to the receptorland.NOTE 1 Multiple handling of soil materials increases the risk of damage to

35、the soilstructure.Before commencing work on a site, subsoil from all areas that are to bedisturbed by construction activities or driven over by vehicles shall be stripped.NOTE 2 Stripping should be done by earthmoving plant that is appropriate to thesize of the site, the volume of soil to be strippe

36、d and the haul distances.BRITISH STANDARD BS 8601:2013 The British Standards Institution 2013 7NOTE 3 The selection of appropriate equipment and work practices is alsoimportant because mishandling subsoil can have an adverse effect on its properties,especially the permeability, which can result in w

37、aterlogging of the topsoil, reducerecharge of underlying aquifers, and increase the risk of flooding and off-sitedischarges which can breach water discharge consents.The operation shall follow a detailed stripping plan showing soil units to bestripped, haul routes and the phasing of vehicle movement

38、s. The soil units shallbe identified on the site with information to distinguish types and layers, andranges of thickness.NOTE 4 It is essential that the stripping is adequately supervised to ensure that thestripping plan is adhered to.Subsoil and topsoil shall be stripped separately and they shall

39、be kept separate.Subsoils of different quality shall also be kept separate from each other.NOTE 5 Figure 2 shows the preferred method of soil stripping. Within each soil unitthe soil layers above the base/formation layer are removed in sequential strips thatcan be up to 6 m wide (the reach of a 360

40、excavator). Using an excavator bucketwith teeth is preferable to using one without. Where there is a cover of topsoil, thatlayer is removed first before stripping subsoil to the specified depth. The soiltransport vehicle runs on the layer beneath the subsoil, not on the subsoil.NOTE 6 Alternative st

41、ripping methods that can be shown to afford the samedegree of soil protection are acceptable.NOTE 7 An archaeological watching brief might have to be accommodated duringsubsoil stripping.Figure 2 Preferred method of stripping subsoilKey1 Topsoil2 Progressive removal3 Next strips4 Subsoil5 Current st

42、rip6 Basal layer6.2 Storing subsoilCOMMENTARY ON 6.2Subsoil often has to be stripped or excavated during a construction process. Inorder to enable its reuse on site at a later stage, the subsoil needs to be storedin temporary stockpiles to minimize the surface area occupied, and to preventdamage fro

43、m the weather and other construction activities.The stockpiling of subsoils shall be avoided whenever possible.BRITISH STANDARDBS 8601:20138 The British Standards Institution 2013NOTE 1 If subsoil loses physical quality, diffusion of oxygen and permeability arereduced.Where stockpiling is unavoidabl

44、e, heaps shall be tipped loosely and the surfacefirmed and shaped to shed water.NOTE 2 Figure 3 illustrates a preferred method of stockpiling stripped subsoil.Stockpiles shall be sited so as to avoid any risk that muddy water could run offdirectly or indirectly into watercourses.The site of a stockp

45、ile shall be prepared thoroughly in advance by grading andby removing rubbish etc. Topsoil and subsoil shall be removed from sitesdesignated for stockpiling subsoil. Subsoil shall be stockpiled separately fromtopsoil and other excavated materials.NOTE 3 Stockpiles left in situ for long periods shoul

46、d be managed to preventseeding, especially from adjacent land.Figure 3 Preferred method of stockpiling dry non-plastic subsoilabcdeKeya Placing first layerb Levelling first layerc Placing second layerd Levelling second layere Levelling top layerBRITISH STANDARD BS 8601:2013 The British Standards Ins

47、titution 2013 96.3 Depths of subsoil and topsoil on a landscaped siteOn a landscaped site, the combined minimum depth of subsoil and topsoilplaced shall be 450 mm for grass, 600 mm for shrubs and 900 mm for trees.NOTE The depth of topsoil spread should not normally exceed 300 mm.6.4 Preparation of t

48、he receiving area and spreading of subsoilCOMMENTARY ON 6.4The functioning of subsoil within a landscape depends not only on the quality of thesubsoil but also on the care given to the preparation of the receiving area, whichwill often have been compacted by the passage of vehicles or storage of mat

49、erials.Prior to spreading subsoil, the receiving area shall be decompacted to increasepermeability.NOTE 1 It is particularly important that the subsoil is not over-compacted duringspreading. Over-compaction prevents plant root growth and function, and reduceswater attenuation and the ability of excess water to drain away through the subsoil.It is one of the most common reasons for plant failures in landscape schemes, and itincreases the risk of erosion and runoff. Placement of soil by tracked hydraulicexcavators working in strips from grou