TheorySECTION 2.0 SETTELMENT CALCULATION2.1 Schmertmann's MethodSchmertmann's method (Schmertmann, 1970, 1978; and Schmertmann et al., 1978) is a popular and useful techniquefor computing the settlement of footings on cohesionless soils.This method is more precise than either th Modified Meyerhof or Burland and Burbidge methods because:- It is based on cone penetration test (CPT) data, which has much greater resolution and precision than thestandard penetration test (SPT). (It's also possible to use this method with other data, including the SPT)- It allows the engineer to divide the soil into layers and assign a different modulus to each layer, while the othermethods require a single N60 value. This is especially useful in complex soil profiles.- This method considers the relative importance of each layer through the use of strain influence factors.2.2 Schmertmann's ProcedureSTEP-1Perform appropriate in-situ tests to determine the modulus, Es, of the soil and its variation with depth.STEP-2Consider the soil from the base of the footing to the depth of influence below the base of to anincompressible strata, whicherer is shallower.STEP-3The strain influence factor varies with depth, as shown in Fig.1.To compute the magnitude of this factor for each layer, it is first necessary to determine thepeak value, Izp :Izp = 0.5 + 0.1 (q' / 'zp)(Eq. 1)where,Izp =peak strain influence factorq' =net bearing pressure (= q - 'vo)'zp=effective overburden pressure at foundation level(depth = Df + B/2 for square and circular footings, D + B for continuous footings)zf =depth below bottom of footingSTEP-4Compute the strain influence factor at the midpoint of each layer:STEP-5Compute the settlement = C1 x C2 x C3 x q ' x (Izi x Hi / Esi)(Eq. 2)where, =settlement of FootingC1 =depth factor = 1 - 0.5 ('vo / q')C2 =creep factor = 1 + 0.2 log10(time in years / 0.1)C3 =shape factor = 1.03 - 0.03 L/B 0.73q' =net bearing pressure (q - 'vo)Hi =thickness of soil layer IEsi =modulus of soil layer iIzi =Iz at midpoint of soil layer i'vo =effective stress at a depth Df below the ground surface

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Soil Parameter2.3 Soil Design ParametersFor Soil Properties (refer to Foundation Design Basis, Sect. 3, Table 1)LayerDescriptionthick of layerBulk DensityElastic Modulus1Residual Soil (RS)0.5 m - 1.0 m18 kN/m3-2Weathered Limestone (WSL)> 10.0 m20 kN/m350.0 MPa3Simsima Limestone (SL)24 kN/m34900.0 MPaThree different types of strata exist at the project site, they are Residual Soil "RS", Weathered Simsima Limestone "WSL",and Simsima Limestone "SL". "RS" is a thin layer of unconsolidated gravely sand overlying limestone.The most of the "RS" layer will be removed to the level of +2.95 QNHD (= EL. 99.8m) during site construction work.Also, Engineering fill will be used to replace the deleterious natural material or to raise natural ground surface elevationsto required levels.Therefore, settlement for important equipment (heavy equipments, tall tower, etc.) will be occurred in this filling layer.ConclusionOn the basis of the above mentioned, the soil design parameters for settlement calculation will be taken asfollowing Table.(Soil Design Parametes for Settlement Calculation)LayerDescriptionthick of layerBulk DensityElastic Modulus1Engineering Fill 5.0 m19 kN/m325.0 MPa2Weathered Limestone (WSL)> 10.0 m20 kN/m350.0 MPa3Simsima Limestone (SL)> 10.0 m24 kN/m34900.0 MPa

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Calculation2.3 Settlement CalculationFooting dimensionWidth (B)Length (L)Depth (Df)hfL/BFooting Shape2.50 m30.00 m2.00 m2.00 m12CONFooting shapeL/B = 1,: Square (SQU) and Circular Footings (CIR)L/B 10,: Continuous Footings (CON)1< L/B < 10,: Rectangular Footings (REC)Depth of influence =12.0 mwhere,Square or Rec Shape =Df + 2B =7.0 mContinuous Shape =Df + 4B =12.0 mEffective stress at a depth Df below the ground surface ('vo)- 'vo =38.00kN/m2where,For Case-1 : 'vo =(s x Df)For Case-2 : 'vo =(s x hf) + (s - w) x (Df - hf)Initial vertical effective stress at a depth of Izp ('zp)- 'zp =61.00kN/m2- 'zp(squ) =49.50kN/m2: (For Square Shape Footing)where,'zp(squ) =(s x hf) + (s - w) x (Df + B/2 - hf): For hf < Df + B/2'zp(squ) =s x (Df + B/2): For hf > Df + B/2- 'zp(con) =61.00kN/m2: (For Continuous Shape Footing)where,'zp(con) =(s x hf) + (s - w) x (Df + B - hf): For hf < Df + B'zp(con) =s x (Df + B): For hf > Df + BBearing pressure at bottom of footing (q)- q =150.00kN/m2Peak strain influence factor (Izp)- Izp(squ) =0.5 + 0.1 (q' / 'zp(squ)) =0.650- Izp(con) =0.5 + 0.1 (q' / 'zp(con)) =0.636Depth factor (C1)- C1 =1 - 0.5 ('vo / q')=0.830Secondary creep factor (C2)- C2 =1 + 0.2 log10 (t - 0.1)=1.340Time since application of load (yr)- t =50.0 year(t 0.1 yr)Shape factor (C3)- C3 =1.03 - 0.03 (L / B) 0.73=0.730TopBottomEszfzf / BIz(squ)Iz(con)IziHiIzi Hi / Es(m)(m)(kN/m2)(m)(m)(mm)0.02.0Depth interval =0.2 m2.02.2250000.10.040.14400.21740.21740.201.74E-060.211862.22.4250000.30.120.23210.25230.25230.202.02E-060.245812.42.6250000.50.200.32020.28710.28710.202.30E-060.279762.62.8250000.70.280.40820.32190.32190.202.58E-060.313712.83.0250000.90.360.49630.35680.35680.202.85E-060.347663.03.2250001.10.440.58440.39160.39160.203.13E-060.381613.23.4250001.30.520.64210.42650.42650.203.41E-060.415563.43.6250001.50.600.60740.46130.46130.203.69E-060.449513.63.8250001.70.680.57270.49610.49610.203.97E-060.483453.84.0250001.90.760.53790.53100.53100.204.25E-060.517404.04.2250002.10.840.50320.56580.56580.204.53E-060.551354.24.4250002.30.920.46850.60070.60070.204.81E-060.585304.44.6250002.51.000.43380.63490.63490.205.08E-060.618634.64.8250002.71.080.39910.61790.61790.204.94E-060.602144.85.0250002.91.160.36440.60100.60100.204.81E-060.585645.05.2500003.11.240.32970.58410.58410.202.34E-060.284575.25.4500003.31.320.29500.56710.56710.202.27E-060.276325.45.6500003.51.400.26030.55020.55020.202.20E-060.268075.65.8500003.71.480.22560.53330.53330.202.13E-060.259835.86.0500003.91.560.19090.51640.51640.202.07E-060.251586.06.2500004.11.640.15620.49940.49940.202.00E-060.243336.26.4500004.31.720.12150.48250.48250.201.93E-060.235086.46.6500004.51.800.08680.46560.46560.201.86E-060.226836.66.8500004.71.880.05210.44860.44860.201.79E-060.218586.87.0500004.91.960.01740.43170.43170.201.73E-060.210347.07.2500005.12.040.00000.41480.41480.201.66E-060.202097.27.4500005.32.120.00000.39780.39780.201.59E-060.193847.47.6500005.52.200.00000.38090.38090.201.52E-060.185597.67.8500005.72.280.00000.36400.36400.201.46E-060.177347.88.0500005.92.360.00000.34710.34710.201.39E-060.169098.08.2500006.12.440.00000.33010.33010.201.32E-060.160848.28.4500006.32.520.00000.31320.31320.201.25E-060.152608.48.6500006.52.600.00000.29630.29630.201.19E-060.144358.68.8500006.72.680.00000.27930.27930.201.12E-060.136108.89.0500006.92.760.00000.26240.26240.201.05E-060.127859.09.2500007.12.840.00000.24550.24550.209.82E-070.119609.29.4500007.32.920.00000.22860.22860.209.14E-070.111359.49.6500007.53.000.00000.21160.21160.208.46E-070.103119.69.8500007.73.080.00000.19470.19470.207.79E-070.094869.810.0500007.93.160.00000.17780.17780.207.11E-070.0866110.010.2500008.13.240.00000.16080.16080.206.43E-070.0783610.210.4500008.33.320.00000.14390.14390.205.76E-070.0701110.410.6500008.53.400.00000.12700.12700.205.08E-070.0618610.610.8500008.73.480.00000.11000.11000.204.40E-070.0536110.811.0500008.93.560.00000.09310.09310.203.72E-070.0453711.011.2500009.13.640.00000.07620.07620.203.05E-070.0371211.211.4500009.33.720.00000.05930.05930.202.37E-070.0288711.411.6500009.53.800.00000.04230.04230.201.69E-070.0206211.611.8500009.73.880.00000.02540.02540.201.02E-070.0123711.812.0500009.93.960.00000.00850.00850.203.39E-080.0041212.0N/A !5000000.000.00000.00000.00000.000.00E+000.00000N/A !N/A !5000000.000.00000.00000.00000.000.00E+000.00000total =11.642 mm

L or HYFOS MAX. BEARING PRESSURE .

SummarySECTION 3.0 RESULT SUMMARY FOR SETTELMENT CALCULATION

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H_steelSIZEH(mm)B(mm)t1(mm)t2(mm)r(mm)A(cm2)U.W.(kg/m)Ix(cm4)Iy(cm4)ix(cm)iy(cm)Zx(cm3)Zy(cm3)H100x100100100681021.917.23831344.182.4776.526.7H125x1251251256.591030.3123.88472935.293.1113647H148x100148100691126.8421.110201516.172.3713830.1H200x1002001005.581127.1621.318401348.242.2218426.8H150x1501501507101140.1431.516405636.393.7521975.1H428x407428407203522360.72831190003940018.210.455701930H194x150194150691339.0130.626905078.33.6127767.6H200x2002002008121365.5349.9472016008.625.02472160H244x1752441757111656.2444.1612098410.44.18502113H250x125250125691237.6629.6405029410.42.7932447H250x2502502509141692.1872.410800365010.86.29867292H294x2002942008121872.3856.811300160012.54.71771160H300x1503001506.591346.7836.7721050812.43.2948167.7H300x300300300101518119.89420400675013.17.511360450H340x25034025091420101.579.721700365014.661280292H350x350350350121920173.9137403001360015.28.842300776H386x29938629991422120.194.333700624016.77.811740418H390x30039030010162213610738700721016.97.281980481H400x2004002008131684.126623700174016.84.541190174H500x200500200101620114.289.647800214020.54.331910214H600x200600200111722134.4106776002280244.122590228H400x400400400132122218.7172666002240017.510.133301120H414x405414405182822295.4232928003100017.710.244801530H440x300440300111824157.412456100811018.97.182550541H488x300488300111826163.512871000811020.87.042910541H582x300582300121728174.5137103000767024.36.633530511H588x300588300122028192.5151118000902024086.854020601H594x302594302142328222.41751370001060024.96.94620701H700x300700300132428235.51852010001080029.36.785760722H800x300800300142628267.421029200011700336.627290782H900x300900300162818305.82404040001260036.46.438990842T125x125125125691218.8312.82481473.632.7925.623.5T150x1501501506.591323.3918.44642544.453.294033.8T175x1751751757111431.5724.88154925.083.9559.356.2T200x2002002008131642.063314008685.764.5488.686.8C100x501005058811.929.36188263.971.4837.67.52C150x75150756.5101023.7118.68611176.032.2211522.4C200x80200807.5111231.3324.619501687.882.3219529.1C250x90250909131444.0734.641802949.742.5833444.5L75x75757568.58.7276.8546.146.12.32.38.478.47L80x8080807L90x9090909L100x10010010010

revison_noteREVISION NOTESThis revised calculation notes (Revision No.1) have been made to incorporate TSP comments,TSP/PJ/013-HS/TP-M0037 dated December 22, 1999 and the revised loading data.Major revision are as follows :1. Story drift with maximum inelastic response displacement have been checked as per UBC 971630. 9. 22. The revised piping loading data have been incorporated, which led to a changeof member size and geometry in Rev. 03. Due to above revision, the computer output and review results of structural analysis havebeen partially revised.

sectionH100x100x6x8H125x125x6.5x9H148x100x6x9H200x100x5.5x8H150x150x7x10H428x407x20x35H194x150x6x9H200x200x8x12H244x175x7x11H250x125x6x9H250x250x9x14H294x200x8x12H300x150x6.5x9H300x300x10x15H340x250x9x14H350x350x12x19H386x299x9x14H390x300x10x16H400x200x8x13H500x200x10x16H600x200x11x17H400x400x13x21H414x405x18x28H440x300x11x18H488x300x11x18H582x300x12x17H588x300x12x20H594x302x14x23H700x300x13x24H800x300x14x26H900x300x16x28T125x125x6x9T150x150x6.5x9T175x175x7x11T200x200x8x13C100x50x5x7.5C150x75x6.5x10C200x80x7.5x11C250x90x9x13L75x75x6xL80x80x7xL90x90x9xL100x100x10x