印度地勘翻译1.doc

SECTION IV8.0. Discussions, Analysis & Recommendation（讨论、分析及建议）Sub-soil conditions and the engineering properties of different layers as revealed by the investigation are described above.（上文介绍了土壤情况和不同土层的工程特性）Aspects of safe bearing capacity and settlement of shallow foundations as well as deep foundation in the form of RCC Bored Cast In-situ Piles are discussed hereunder. (下文讨论混凝土钻孔灌注桩的安全承载力和深、浅基础的沉降情况)Selection of suitable foundation depends on the following factors : (选择合适的基础取决于以下几个因素)1. Safe bearing pressure on founding soil (土层的承载力)2. Settlement of foundations should be within allowable limits （地基的沉降应在允许的范围内）3. Cost of foundation construction （基础的施工成本）4. Construction aspects e.g. excavation, ground water table etc. （施工方面例如，开挖、施工水位等）INTRODUCTIONThe borelog data of 16 Nos. of boreholes ( BH - 5, 14, 16, 21, 47, 54, 64, 71, 74, 75, 78, 86, 93, 94, 108, 117), sunk in the locations as directed by client in the proposed Pellet Plant area of Usha Martin-Jamshedpur site, reveal that, the sub-surface stratification at this site varies in terms of depth, thickness & compactness of underlying strata.（16个钻孔的柱状图显示：场地下地层的深度、厚度、密实度是变化的）The sequence of occurrence shows that, in general, below the top uncontrolled, erratic, heterogeneous Fill (Stratum-I), there exists a stiff to very stiff, yellowish brown, silty Clay layer (Stratum -II) overlying a brownish yellow, dense to very dense, residual, silty Sand layer (Stratum-III). (地层-I是不稳定、非均质的填土，地层-II是僵硬、黄棕色的粉质粘土层，地层-III上是棕黄色、非常密实的、残余的粉砂层) This is followed by a highly weathered, disintegrated, decomposed, brownish yellow, mica-schist rock layer (Stratum-IV) continued upto the maximum depth of exploration.(地层-IV：高度风化，分解，呈棕黄色云母片岩岩石层，并一直持续到勘探最深处) For depth & thickness of different strata, at different borehole locations, as obtained during investigation, the attached bore logs may be referred.It is learnt that, the final Terrace Level (TL) of the subject area is 158.5 m. （场地0.00相当于绝对标高158.5m）During investigation, it was found that the Existing Ground Levels (EGL) of the proposed Pellet Plant site were found to vary in between 160.328m to 163.396m RL at different borehole points.(在不同的钻孔点场地自然标高在160.328m和163.96之间) The investigation has been conducted from such prevailing ground level. After complete site terracing, depth of different layers w.r.t. TL, as well as individual layer thickness, will change depending on extent of cutting/filling at that particular location. Thus, borehole-wise post-terracing stratification scenario has been furnished in the following table, for better understanding of actual foundation model.Borehole-wise Post-Terracing Stratification Details ( w.r.t. TL =158.5m )(钻孔分层详情)Borehole（钻孔）Co-Ordinate（坐标）Post-terracing Thickness of Fill(overlying Stratum -II)(m) （地层- II顶部距0.00距离）Depth of top of Stratum -III, from TL(m) （地层- III顶部距0.00距离）Depth of top of highly weathered Rock layer(Stratum -IV), from TL(m)（地层-IV顶部距0.00距离）BH-5X(-) 173, Y (-) 2974.316.618.91BH-14X (-) 173, Y (-) 1574.666.368.26BH-16X (-) 167, Y (-) 1274.036.328.13BH-21X (-) 158, Y (-) 744.036.837.83BH-47X (-) 137, Y (-) 733.235.638.08BH-54X (-) 140, Y (-) 1535.255.256.55BH-64X (-) 232, Y (-) 16410.3913.6414.44BH-71X (-) 250, Y (-) 1004.656.5910.35BH-74X (-) 250, Y (-) 845.017.2110.11BH-75X (-) 250, Y (-) 623.685.837.08BH-78X (-) 265, Y (-) 454.576.577.77BH-86X (-) 272, Y (+) 41.553.264.70BH-93X (-) 242, Y (+) 1031.304.504.80BH-94X (-) 275, Y (+) 472.755.407.10BH-108X (-) 193, Y (+) 1011.392.945.24BH-117X (-) 94, Y (-) 422.715.366.76DESIGN GEOTECHNICAL MODEL （设计岩土工程模型）Geotechnical judgment has been applied on field observation, field data, local geomorphology, ground water condition & laboratory test results of the sub-surface materials encountered at different depths in different boreholes at this site, to arrive at rational design parameters. Representative relevant geotechnical parameters are judiciously considered as follows (有关岩土参数如下)Stratum - I (Fill) (地层-I填土): This is the top Fill layer, made up by uncontrolled dumping of coal dust & other heterogeneous materials. (填土层是由倾倒的煤灰和其他非均质物质组成) The nomenclature of Stratum-I used in this report, includes the existing erratic, Fill encountered during investigation, as well as, the fill of similar nature expected to be used in further site-terracing, wherever required. The highly heterogeneous, unpredictable nature of such fill , makes it extremely unreliable medium for placing any industrial foundation of the proposed plant.(由于不均质性和不可预测性，任何拟建厂房基础落于尺寸都是非常不可靠的) Thus, parameters of this Fill are not relevant for the present purpose（此层参数不再给出）Stratum - II （地层-II） Cohesion, C = 0.55 Kg/cm2 ,（内聚力C= 0.55 Kg/cm2 ,） Angle of Internal Friction, = 0, (内摩擦角=0) Bulk Density, = 1.75 gm/cc （容重= 1.75 gm/cc）Co-efficient of volume compressibility,（体积压缩系数）mv =0.013 cm2 / Kg (for relevant pressure range)The field N values have been judiciously rationalized, considering the fact that, some non-representative high N values in Stratum- III occurred due to encountering of rock fragments present in matrix of residual soil, by SPT cutting shoe. Accordingly, the design parameters of Stratum-III are frozen, apparently on conservative side.（为保守起见地层-III的参数不使用）Effect of Ground Water Table (GWT) has been duly considered in laboratory testing &geotechnical analysis, considering the worst possible ground water condition during heavy monsoon rain.（实验室测试和工程分析已经考虑在雨季最坏情况下地下水位的影响） To simulate worst possible Ground Water Condition, all shear strength tests were conducted after complete saturation of samples, wherever required(为了模拟最坏的地表水条件，所有剪切强度试验都是在土样完全饱和后进行的).Stratum IV（地层IV） : Rock Mass characteristics of these deposits have been established from Drill Core study, Microscopic analysis of Rock Specimen, Laboratory test results, Geo-mechanics observation by geologist in nearby natural / man-made excavations & general Geology of this area. Stratum -IV is a highly weathered Mica-Schist layer, properties of which improve with depth.（地层-IV是高度风化的云母片岩层，风化程度随深度减弱）Geotechnical & geological judgment has been applied on Field observation, Field data, Drill Core study, local geology & Laboratory test results of the weathered rock encountered in different boreholes at this site to arrive at rational design geotechnical parameters, keeping in view of local geomorphology. Design RQD % of Stratum -IV is considered as Nil. Laboratory test results reveal that, the representative value of saturated Point Load strength of highly weathered Mica-Schist encountered lower reaches at this site varies from 2.18 kg/cm2 to 5.62 kg/cm2. The orientation of discontinuity in rock mass may be considered as near horizontal, which following the guideline of Fig 1, IS:12070-1987, can be classified as Favorable orientation. The discontinuity planes in this Stratum -IV are Moderately spaced - ranging from 20 to 50 cm, with 1 to 5 mm thickness of discontinuity, with rough & moderately weathered rock surface at discontinuity plane. Considering the disintegrated nature of weathered rock & existence of GWT above weathered rock layer, Ground Water Condition is considered as Flowing. Taking into account of all such above parameters of the Rock Mass as a whole, the highly weathered Mica-Schist layer has been geotechnical y analyzed.representative value代表值；saturated饱和；orientation定位；discontinuity间断rock mass岩体；parameters参数；Mica-Schist云母片岩；FOUNDATION RECOMMENDATION （基础建议）No foundation is recommended in uncontrolled, heterogeneous Fill (Stratum-I), as explained earlier(地层-I上不建议有任何基础).In general, either Open foundation in Stratum-II or Pile foundation terminated in Stratum-IV may be adopted for the proposed structure.（基础落在地层-II或桩基打入地层-IV都是可行方案） Depending on design requirement & constructability considerations, the design engineer may like to choose the most suitable option（根据设计要求和施工条件，设计师可以选择其中最适合的方案）For heavily loaded foundation of the proposed units, wherever recommended Bearing Capacity of Open foundations are found to be inadequate at practicable depth &/or for locations with higher post-terracing Fill thickness, deep foundation in the form of Bored Cast-in-situ RCC pile, terminated with a socketing of not less than 4D in weathered mica-schist rock layer, may be considered. （对于荷载较大基础可以考虑钻孔灌注桩）However, in few locations, due to relatively shallow existence of Stratum-IV, heavier foundations may be placed Stratum-IV.(少数地方地层-IV较浅，大荷载基础可以直接落在上面) In cases, where technological depth calls for placing any foundation at deeper depth, &/or for heavily loaded foundations for which bearing capacity of virgin soil is found to be inadequate, open foundation may be placed in weathered rock layer (Stratum- IV), if found feasible. In very few locations (viz. BH - 86, 108), Stratum-III may be encountered at reasonably shallow depth.（在少数地点地层-III的深度较浅） In such case, open foundation may be placed in Stratum-III, if presence of Stratum-III is confirmed with certainty at site during excavation. （这种情况下，如果现场开挖过程中证实地层III确实存在，基础可以放在地层-III上）OPEN FOUNDATION For open foundation, virgin soil deposit (Stratum-II) may be chosen as founding medium, depending on design loading intensity, depth of weathered rock layer from TL &technological depth for particular foundation. （对于开挖式基础，根据设计荷载、风化岩的埋深以及technological depth for particular foundation可以将地层-II做为持力层）Minimum depth of Open foundation shall be 1.0 m below bottom of Fill, i.e. 1.0 m below Original Ground Level.(开挖式基础最小埋深应在填土层底部向下1m) The following Table shows the location-wise feasibility of open foundation in light of their suggested depths.Borehole-wise Feasibility of Open FoundationBorehole（钻孔）Co-Ordinate（坐标）Recommended Minimum Depth of Open foundation from TL, if placed in（从158.5m（0.00）算起的建议最小埋深）Stratum-IIStratum-IIIStratum-IVBH-5X(-) 173, Y (-) 29BH-14X (-) 173, Y (-) 15BH-16X (-) 167, Y (-) 1275.07.38.7BH-21X (-) 158, Y (-) 745.07.88.4BH-47X (-) 137, Y (-) 7BH-54X (-) 140, Y (-) 1536.2-7.1BH-64X (-) 232, Y (-) 16411.4-15.0BH-71X (-) 250, Y (-) 1005.78.011.0BH-74X (-) 250, Y (-) 846.08.210.7BH-75X (-) 250, Y (-) 6BH-78X (-) 265, Y (-) 4BH-86X (-) 272, Y (+) BH-93X (-) 242, Y (+) 1032.3-5.4BH-94X (-) 275, Y (+) 4BH-108X (-) 193, Y (+) 10BH-117X (-) 94, Y (-) 4OPEN FOUNDATION IN VIRGIN SOILShallow foundation in the form of isolated Square, Rectangular, Strip & Raft of different sizes are judiciously considered at 2.5 m & 5.0 m depth from TL, within Stratum - II. (方形、矩形、条形、筏板浅基础若落在地层-II，埋深应为从0.00向下2.5到5.0m)From the above table, it is evident that, in general, due to higher depth of Stratum-III from TL, placing of Open foundation in Stratum-III may not be a feasible solution from constructability aspect.(从上表看，由于地层-III埋深较深，从施工方面考虑不宜将独立基础落在地层III) Similar logic is valid for Stratum-IV also.（对于地层-IV同样如此） Accordingly, Net Safe Bearing capacities & corresponding settlements are evaluated & tabulated for Stratum-II.（因此，将地层-II的承载力和变形列表）For footing placed at Stratum-II, the total settlement will be contributed by Consolidation settlement of Stratum-II & Elastic settlement of Stratum -III, below footing & upto its influence depth (2B for consolidation settlement & 5B for elastic settlement), subject to maximum extent upto incompressible layer. The weathered rock layer (Stratum -IV), having N 100 al -through, is considered to be incompressible for the purpose of settlement analysis.(地层-IV风化岩的N值始终大于100，所以不考虑它的沉降) While analyzing Net Allowable Bearing capacity, maximum permissible total settlement for isolated footing of industrial structure has been considered as 40 mm（在分析允许承载力后，独立基础的最大沉降量为40mm）. Thus, when the evaluated settlement is less than 40 mm, the Net Safe Bearing capacity becomes Net Allowable Bearing Capacity.（当沉降量小于40mm时，安全承载力变为允许承载力） When the computed settlement is more, the Net Allowable Bearing Capacity is proportionately back figured. Similarly for Raft, permissible total settlement has been considered as 60 mm.（对于筏板基础最大沉降量为60mm） In case, more stringent settlement limit is required by the civil design engineer, he may like to proportionately decrease the Net Allowable Bearing capacity furnished hereinafter, wherever it exceeds the settlement limit assigned by him.Net Safe Bearing Capacity & corresponding Settlement（安全承载力和相应沉降量） for footings of different Shape & Size（对于不同形状、尺寸的基础）, placed at 2.5 m depth from TL subject to at least 1.0 m within Stratum-II（从0.00向下2.5m,至少埋入地层-II 1.0m）Depth (m)埋深Shape形状Size ( m x m )尺寸Net Safe BearingCapacity(Ton/m2 )安全承载力Total Settlement(mm)总沉降量Net Allowable Bearing Capacity(Ton/m2 )允许承载力2.5mFromTLSquare2.0x2.03.0x3.04.0x4.0181717172839181717Rectangle2.0x4.03.0x6.04.0x8.0161514233543161513Strip1.0m wide2.0m wide171416341714Raft10.0x10.010.0x20.0151373721211Note Bearing capacities for intermediate size can be linearly interpolated.（中间尺寸的承载力可以通过线性插值得到） The above Bearing Capacities are applicable for adjacent footings with clear spacing not less than their average width. （上述承载力适用于基础间的距离不小于它们的平均宽度）Net Safe Bearing Capacity & corresponding Settlement（安全承载力和相应沉降量） for footings of different Shape & Size（对于不同形状、尺寸的基础）, placed at 2.5 m depth from TL subject to at least 1.0 m within Stratum-II（从0.00向下5.0m,至少埋入Stratum-II 1.0m）Depth (m)埋深Shape形状Size ( m x m )尺寸Net Safe BearingCapacity(Ton/m2 )安全承载力Total Settlement(mm)总沉降量Net Allowable Bearing Capacity(Ton/m2 )允许承载力5.0mFromTLSquare2.0x2.03.0x3.04.0x4.0201818273138201818Rectangle2.0x4.03.0x6.04.0x8.0171615303538171615Strip1.0m wide2.0m wide171530351715Raft10.0x10.010.0x20.0161450471614Note Bearing capacities for intermediate size can be linearly interpolated.（中间尺寸和埋深的承载力可以通过线性插值得到） The above Bearing Capacities are applicable for adjacent footings with clear spacing not less than their average width. （上述承载力适用于基础间的距离不小于它们的平均宽度）OPEN FOUNDATION IN STRATUM III（在地层III的开挖式基础）In locations, where Stratum-III is encountered at reasonably shallow depth viz. at BH - 86 & 108 locations, Open foundation may be placed in sandy layer of Stratum-III, for which a Net Allowable Bearing Capacity may be considered as 30 ton/m2.(在钻孔86和108处，地层-III的深度较浅，这时基础可以落在其上，它的允许承载力是30 ton/m2)OPEN FOUNDATION IN WEATHERED ROCK LAYER ( STRATUM - IV )（在地层IV上的开挖式基础）In all the boreholes at this site, below the overburden of virgin residual soil (Stratum -II & III), a highly weathered, decomposed, disintegrated, mica-schist rock layer (Stratum -IV) has been encountered, which continues upto the maximum depth of exploration.In cases, where Stratum-IV exists within reasonably shallow depth from TL &/or for heavily loaded structures, for which bearing capacity of virgin soil is inadequate &/or for foundations with greater technological depth, open foundation may be placed in Stratum -IV, for which following Net Allowable Bearing Capacities may be considered.( 当地层-IV的深度较浅或荷载较大且地层-II的承载力不足，或者基础埋深要求比较大时，open基础可以落在地层-IV上，地层-IV的承载力在下表给出)Stratum(地层)Depth（埋深）Net Allowable Bearing Capacity(Ton/m2 )允许承载力Stratum-IV（地层-IV）At least 600 mm within weathered, disintegrated,decomposed mica-schist rock.（进入地层- IV最少600mm）35 ton/m2The weathered Granite-gneiss layers (Stratum -IV) shall be identified at site, by visual inspection of characteristics fabric / texture of rock, encountered in foundation excavation. The investigating agency may be contacted for such services, should any confusion arises at site during execution, regarding identifying of different strata.weathered 风化；Granite-gneiss 花岗片麻岩；visual inspection肉眼观察；texture纹理；excavation开挖；investigating agency调查机构；strata地层；confusion混乱； PILE FOUNDATION（桩基础）Wherever pile foundation is adopted, Bored cast-in-situ concrete pile terminating in Stratum-IV weathered rock layer, with a socket length not less than 4D within such stratum, may be adopted(采用桩基础时，钻孔灌注桩嵌入地层-IV不少于4D). Accordingly, 450 mm, 500 mm, 550 mm, 600 mm, 750 mm & 1000 mm dia bored cast-in-situ RCC pile foundations are analyzed & the recommended capacities are tabulated hereunder（将分析450mm、500mm、550mm、600mm、750mm及1000mm直径的钻孔灌注桩基础）. Vertical capacities of such piles socketed in weathered rock, are evaluated following Cole & Stroud approach, judiciously considering the characteristics of rock mass.Recommended Vertical Capacities of single Pile ( Ton )（单桩垂直承载力 t）TerminationDepth(终孔深度)LoadingPattern（荷载模式）Pile Diameter (mm)（桩径）4505005506007501000with a socket length of not less than 4D within identifiable weathered mica- schist rock layer（进入地层-IV不小于4D）Compressive（受压）7090105125200360Uplift（受拉）20+W25+W30+W37+W58+W103+Wwhere, w = Buoyant weight (ton) of Pile shaft( w=桩身浮力（吨）) The above pile capacities are calculated on the basis of average geotechnical parameters(上述单桩承载力是根据岩土参数计算确定). Ag