UCwallbase

JobNumber:16060243W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx5.
1.
StructuralDesignCalculationsJobNumber:16060244W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxJobNumber:16060245W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxRETAININGWALLDESIGNTEMPORARYCONDITIONThefollowingcalculationswillconsidertheworstcase.
Inthetemporaryconditionnowaterwillbetakenintoaccount.
RETAININGWALLANALYSIS(BS8002:1994)TEDDScalculationversion1.
2.
01.
06WalldetailsRetainingwalltypeCantileverproppedatbaseHeightofretainingwallstemhstem=3500mmThicknessofwallstemtwall=350mmLengthoftoeltoe=3000mmLengthofheellheel=0mmOveralllengthofbaselbase=ltoe+lheel+twall=3350mmThicknessofbasetbase=350mmDepthofdownstanddds=0mmPositionofdownstandlds=1900mmThicknessofdownstandtds=350mmHeightofretainingwallhwall=hstem+tbase+dds=3850mmDepthofcoverinfrontofwalldcover=0mmDepthofunplannedexcavationdexc=0mmHeightofgroundwaterbehindwallhwater=0mmHeightofsaturatedfillabovebasehsat=max(hwater-tbase-dds,0mm)=0mmDensityofwallconstructionJwall=23.
6kN/m3DensityofbaseconstructionJbase=23.
6kN/m3AngleofrearfaceofwallD=90.
0degAngleofsoilsurfacebehindwallE=0.
0degEffectiveheightatvirtualbackofwallheff=hwall+lheelutan(E)=3850mmJobNumber:16060246W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxRetainedmaterialdetailsMobilisationfactorM=1.
5MoistdensityofretainedmaterialJm=18.
0kN/m3SaturateddensityofretainedmaterialJs=21.
0kN/m3DesignshearstrengthI'=24.
2degAngleofwallfrictionG=0.
0degBasematerialdetailsMoistdensityJmb=18.
0kN/m3DesignshearstrengthI'b=24.
2degDesignbasefrictionGb=18.
6degAllowablebearingpressurePbearing=100kN/m2UsingCoulombtheoryActivepressurecoefficientforretainedmaterialKa=sin(D+I')2/(sin(D)2usin(D-G)u[1+(sin(I'+G)usin(I'-E)/(sin(D-G)usin(D+E)))]2)=0.
419PassivepressurecoefficientforbasematerialKp=sin(90-I'b)2/(sin(90-Gb)u[1-(sin(I'b+Gb)usin(I'b)/(sin(90+Gb)))]2)=4.
187At-restpressureAt-restpressureforretainedmaterialK0=1–sin(I')=0.
590LoadingdetailsSurchargeloadonplanSurcharge=10.
0kN/m2AppliedverticaldeadloadonwallWdead=85.
6kN/mAppliedverticalliveloadonwallWlive=3.
8kN/mPositionofappliedverticalloadonwalllload=3150mmAppliedhorizontaldeadloadonwallFdead=0.
0kN/mAppliedhorizontalliveloadonwallFlive=0.
0kN/mHeightofappliedhorizontalloadonwallhload=0mmLoadsshowninkN/m,pressuresshowninkN/m2JobNumber:16060247W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxVerticalforcesonwallWallstemwwall=hstemutwalluJwall=28.
9kN/mWallbasewbase=lbaseutbaseuJbase=27.
7kN/mAppliedverticalloadWv=Wdead+Wlive=89.
4kN/mTotalverticalloadWtotal=wwall+wbase+Wv=146kN/mHorizontalforcesonwallSurchargeFsur=KauSurchargeuheff=16.
1kN/mMoistbackfillabovewatertableFm_a=0.
5uKauJmu(heff-hwater)2=55.
8kN/mTotalhorizontalloadFtotal=Fsur+Fm_a=71.
9kN/mCalculateproppingforcePassiveresistanceofsoilinfrontofwallFp=0.
5uKpucos(Gb)u(dcover+tbase+dds-dexc)2uJmb=4.
4kN/mProppingforceFprop=max(Ftotal-Fp-(Wtotal-Wlive)utan(Gb),0kN/m)Fprop=19.
7kN/mOverturningmomentsSurchargeMsur=Fsuru(heff-2udds)/2=31kNm/mMoistbackfillabovewatertableMm_a=Fm_au(heff+2uhwater-3udds)/3=71.
7kNm/mTotaloverturningmomentMot=Msur+Mm_a=102.
7kNm/mRestoringmomentsWallstemMwall=wwallu(ltoe+twall/2)=91.
8kNm/mWallbaseMbase=wbaseulbase/2=46.
3kNm/mDesignverticaldeadloadMdead=Wdeadulload=269.
6kNm/mTotalrestoringmomentMrest=Mwall+Mbase+Mdead=407.
8kNm/mCheckbearingpressureDesignverticalliveloadMlive=Wliveulload=12kNm/mTotalmomentforbearingMtotal=Mrest-Mot+Mlive=317.
1kNm/mTotalverticalreactionR=Wtotal=146.
0kN/mDistancetoreactionxbar=Mtotal/R=2172mmEccentricityofreactione=abs((lbase/2)-xbar)=497mmReactionactswithinmiddlethirdofbaseBearingpressureattoeptoe=(R/lbase)-(6uRue/lbase2)=4.
8kN/m2Bearingpressureatheelpheel=(R/lbase)+(6uRue/lbase2)=82.
4kN/m2PASS-MaximumbearingpressureislessthanallowablebearingpressureJobNumber:16060248W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxRETAININGWALLDESIGN(BS8002:1994)TEDDScalculationversion1.
2.
01.
06UltimatelimitstateloadfactorsDeadloadfactorJf_d=1.
4LiveloadfactorJf_l=1.
6EarthandwaterpressurefactorJf_e=1.
4FactoredverticalforcesonwallWallstemwwall_f=Jf_duhstemutwalluJwall=40.
5kN/mWallbasewbase_f=Jf_dulbaseutbaseuJbase=38.
7kN/mAppliedverticalloadWv_f=Jf_duWdead+Jf_luWlive=125.
9kN/mTotalverticalloadWtotal_f=wwall_f+wbase_f+Wv_f=205.
1kN/mFactoredhorizontalat-restforcesonwallSurchargeFsur_f=Jf_luK0uSurchargeuheff=36.
3kN/mMoistbackfillabovewatertableFm_a_f=Jf_eu0.
5uK0uJmu(heff-hwater)2=110.
2kN/mTotalhorizontalloadFtotal_f=Fsur_f+Fm_a_f=146.
6kN/mCalculateproppingforcePassiveresistanceofsoilinfrontofwallFp_f=Jf_eu0.
5uKpucos(Gb)u(dcover+tbase+dds-dexc)2uJmb=6.
1kN/mProppingforceFprop_f=max(Ftotal_f-Fp_f-(Wtotal_f-Jf_luWlive)utan(Gb),0kN/m)Fprop_f=73.
4kN/mFactoredoverturningmomentsSurchargeMsur_f=Fsur_fu(heff-2udds)/2=70kNm/mMoistbackfillabovewatertableMm_a_f=Fm_a_fu(heff+2uhwater-3udds)/3=141.
4kNm/mTotaloverturningmomentMot_f=Msur_f+Mm_a_f=211.
4kNm/mRestoringmomentsWallstemMwall_f=wwall_fu(ltoe+twall/2)=128.
5kNm/mWallbaseMbase_f=wbase_fulbase/2=64.
9kNm/mDesignverticalloadMv_f=Wv_fulload=396.
6kNm/mTotalrestoringmomentMrest_f=Mwall_f+Mbase_f+Mv_f=590kNm/mFactoredbearingpressureTotalmomentforbearingMtotal_f=Mrest_f-Mot_f=378.
6kNm/mTotalverticalreactionRf=Wtotal_f=205.
1kN/mDistancetoreactionxbar_f=Mtotal_f/Rf=1846mmEccentricityofreactionef=abs((lbase/2)-xbar_f)=171mmReactionactswithinmiddlethirdofbaseBearingpressureattoeptoe_f=(Rf/lbase)-(6uRfuef/lbase2)=42.
5kN/m2Bearingpressureatheelpheel_f=(Rf/lbase)+(6uRfuef/lbase2)=80kN/m2Rateofchangeofbasereactionrate=(ptoe_f-pheel_f)/lbase=-11.
19kN/m2/mBearingpressureatstem/toepstem_toe_f=max(pheel_f+(rateu(lheel+twall)),0kN/m2)=76.
1kN/m2Bearingpressureatmidstempstem_mid_f=max(pheel_f+(rateu(lheel+twall/2)),0kN/m2)=78kN/m2Bearingpressureatstem/heelpstem_heel_f=max(pheel_f+(rateulheel),0kN/m2)=80kN/m2Designofreinforcedconcreteretainingwalltoe(BS8002:1994)MaterialpropertiesCharacteristicstrengthofconcretefcu=40N/mm2JobNumber:16060249W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCharacteristicstrengthofreinforcementfy=500N/mm2BasedetailsMinimumareaofreinforcementk=0.
13%Covertoreinforcementintoectoe=30mmCalculateshearfortoedesignShearfrombearingpressureVtoe_bear=(ptoe_f+pstem_toe_f)ultoe/2=177.
8kN/mShearfromweightofbaseVtoe_wt_base=Jf_duJbaseultoeutbase=34.
7kN/mTotalshearfortoedesignVtoe=Vtoe_bear-Vtoe_wt_base=143.
1kN/mCalculatemomentfortoedesignMomentfrombearingpressureMtoe_bear=(2uptoe_f+pstem_mid_f)u(ltoe+twall/2)2/6=273.
9kNm/mMomentfromweightofbaseMtoe_wt_base=(Jf_duJbaseutbaseu(ltoe+twall/2)2/2)=58.
3kNm/mTotalmomentfortoedesignMtoe=Mtoe_bear-Mtoe_wt_base=215.
6kNm/mChecktoeinbendingWidthoftoeb=1000mm/mDepthofreinforcementdtoe=tbase–ctoe–(Itoe/2)=310.
0mmConstantKtoe=Mtoe/(budtoe2ufcu)=0.
056CompressionreinforcementisnotrequiredLeverarmztoe=min(0.
5+(0.
25-(min(Ktoe,0.
225)/0.
9)),0.
95)udtoeztoe=289mmAreaoftensionreinforcementrequiredAs_toe_des=Mtoe/(0.
87ufyuztoe)=1713mm2/mMinimumareaoftensionreinforcementAs_toe_min=kubutbase=455mm2/mAreaoftensionreinforcementrequiredAs_toe_req=Max(As_toe_des,As_toe_min)=1713mm2/mReinforcementprovided20mmdia.
bars@150mmcentresAreaofreinforcementprovidedAs_toe_prov=2094mm2/mPASS-ReinforcementprovidedattheretainingwalltoeisadequateCheckshearresistanceattoeDesignshearstressvtoe=Vtoe/(budtoe)=0.
462N/mm2Allowableshearstressvadm=min(0.
8u(fcu/1N/mm2),5)u1N/mm2=5.
000N/mm2PASS-DesignshearstressislessthanmaximumshearstressFromBS8110:Part1:1997–Table3.
8Designconcreteshearstressvc_toe=0.
691N/mm2vtoe0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxDesignofreinforcedconcreteretainingwallstem(BS8002:1994)MaterialpropertiesCharacteristicstrengthofconcretefcu=40N/mm2Characteristicstrengthofreinforcementfy=500N/mm2WalldetailsMinimumareaofreinforcementk=0.
13%Covertoreinforcementinstemcstem=30mmCovertoreinforcementinwallcwall=30mmFactoredhorizontalat-restforcesonstemSurchargeFs_sur_f=Jf_luK0uSurchargeu(heff-tbase-dds)=33kN/mMoistbackfillabovewatertableFs_m_a_f=0.
5uJf_euK0uJmu(heff-tbase-dds-hsat)2=91.
1kN/mCalculateshearforstemdesignShearatbaseofstemVstem=Fs_sur_f+Fs_m_a_f-Fprop_f=50.
7kN/mCalculatemomentforstemdesignSurchargeMs_sur=Fs_sur_fu(hstem+tbase)/2=63.
6kNm/mMoistbackfillabovewatertableMs_m_a=Fs_m_a_fu(2uhsat+heff-dds+tbase/2)/3=122.
2kNm/mTotalmomentforstemdesignMstem=Ms_sur+Ms_m_a=185.
8kNm/mCheckwallsteminbendingWidthofwallstemb=1000mm/mDepthofreinforcementdstem=twall–cstem–(Istem/2)=310.
0mmConstantKstem=Mstem/(budstem2ufcu)=0.
048CompressionreinforcementisnotrequiredLeverarmzstem=min(0.
5+(0.
25-(min(Kstem,0.
225)/0.
9)),0.
95)udstemzstem=292mmAreaoftensionreinforcementrequiredAs_stem_des=Mstem/(0.
87ufyuzstem)=1461mm2/mMinimumareaoftensionreinforcementAs_stem_min=kubutwall=455mm2/mAreaoftensionreinforcementrequiredAs_stem_req=Max(As_stem_des,As_stem_min)=1461mm2/mReinforcementprovided20mmdia.
bars@150mmcentresAreaofreinforcementprovidedAs_stem_prov=2094mm2/mPASS-ReinforcementprovidedattheretainingwallstemisadequateCheckshearresistanceatwallstemDesignshearstressvstem=Vstem/(budstem)=0.
163N/mm2Allowableshearstressvadm=min(0.
8u(fcu/1N/mm2),5)u1N/mm2=5.
000N/mm2JobNumber:16060251W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxPASS-DesignshearstressislessthanmaximumshearstressFromBS8110:Part1:1997–Table3.
8Designconcreteshearstressvc_stem=0.
691N/mm2vstem0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxIndicativeretainingwallreinforcementdiagramToebars-20mmdia.
@150mmcentres-(2094mm2/m)Stembars-20mmdia.
@150mmcentres-(2094mm2/m)RETAININGWALLDESIGNPERMANENTDESIGNThefollowingcalculationswilltakeintoconsiderationthehydrostaticpressuretotherearofthewall.
RETAININGWALLANALYSIS(BS8002:1994)TEDDScalculationversion1.
2.
01.
06ToereinforcementStemreinforcementJobNumber:16060253W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxWalldetailsRetainingwalltypeCantileverproppedatbaseHeightofretainingwallstemhstem=3500mmThicknessofwallstemtwall=350mmLengthoftoeltoe=3000mmLengthofheellheel=0mmOveralllengthofbaselbase=ltoe+lheel+twall=3350mmThicknessofbasetbase=350mmDepthofdownstanddds=0mmPositionofdownstandlds=1900mmThicknessofdownstandtds=350mmHeightofretainingwallhwall=hstem+tbase+dds=3850mmDepthofcoverinfrontofwalldcover=0mmDepthofunplannedexcavationdexc=0mmHeightofgroundwaterbehindwallhwater=2500mmHeightofsaturatedfillabovebasehsat=max(hwater-tbase-dds,0mm)=2150mmDensityofwallconstructionJwall=23.
6kN/m3DensityofbaseconstructionJbase=23.
6kN/m3AngleofrearfaceofwallD=90.
0degAngleofsoilsurfacebehindwallE=0.
0degEffectiveheightatvirtualbackofwallheff=hwall+lheelutan(E)=3850mmRetainedmaterialdetailsMobilisationfactorM=1.
5MoistdensityofretainedmaterialJm=18.
0kN/m3SaturateddensityofretainedmaterialJs=21.
0kN/m3DesignshearstrengthI'=24.
2degAngleofwallfrictionG=0.
0degJobNumber:16060254W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxBasematerialdetailsMoistdensityJmb=18.
0kN/m3DesignshearstrengthI'b=24.
2degDesignbasefrictionGb=18.
6degAllowablebearingpressurePbearing=100kN/m2UsingCoulombtheoryActivepressurecoefficientforretainedmaterialKa=sin(D+I')2/(sin(D)2usin(D-G)u[1+(sin(I'+G)usin(I'-E)/(sin(D-G)usin(D+E)))]2)=0.
419PassivepressurecoefficientforbasematerialKp=sin(90-I'b)2/(sin(90-Gb)u[1-(sin(I'b+Gb)usin(I'b)/(sin(90+Gb)))]2)=4.
187At-restpressureAt-restpressureforretainedmaterialK0=1–sin(I')=0.
590LoadingdetailsSurchargeloadonplanSurcharge=10.
0kN/m2AppliedverticaldeadloadonwallWdead=85.
6kN/mAppliedverticalliveloadonwallWlive=3.
8kN/mPositionofappliedverticalloadonwalllload=3150mmAppliedhorizontaldeadloadonwallFdead=0.
0kN/mAppliedhorizontalliveloadonwallFlive=0.
0kN/mHeightofappliedhorizontalloadonwallhload=0mmLoadsshowninkN/m,pressuresshowninkN/m2VerticalforcesonwallWallstemwwall=hstemutwalluJwall=28.
9kN/mWallbasewbase=lbaseutbaseuJbase=27.
7kN/mAppliedverticalloadWv=Wdead+Wlive=89.
4kN/mTotalverticalloadWtotal=wwall+wbase+Wv=146kN/mJobNumber:16060255W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxHorizontalforcesonwallSurchargeFsur=KauSurchargeuheff=16.
1kN/mMoistbackfillabovewatertableFm_a=0.
5uKauJmu(heff-hwater)2=6.
9kN/mMoistbackfillbelowwatertableFm_b=KauJmu(heff-hwater)uhwater=25.
4kN/mSaturatedbackfillFs=0.
5uKau(Js-Jwater)uhwater2=14.
6kN/mWaterFwater=0.
5uhwater2uJwater=30.
7kN/mTotalhorizontalloadFtotal=Fsur+Fm_a+Fm_b+Fs+Fwater=93.
7kN/mCalculateproppingforcePassiveresistanceofsoilinfrontofwallFp=0.
5uKpucos(Gb)u(dcover+tbase+dds-dexc)2uJmb=4.
4kN/mProppingforceFprop=max(Ftotal-Fp-(Wtotal-Wlive)utan(Gb),0kN/m)Fprop=41.
5kN/mOverturningmomentsSurchargeMsur=Fsuru(heff-2udds)/2=31kNm/mMoistbackfillabovewatertableMm_a=Fm_au(heff+2uhwater-3udds)/3=20.
3kNm/mMoistbackfillbelowwatertableMm_b=Fm_bu(hwater-2udds)/2=31.
8kNm/mSaturatedbackfillMs=Fsu(hwater-3udds)/3=12.
2kNm/mWaterMwater=Fwateru(hwater-3udds)/3=25.
5kNm/mTotaloverturningmomentMot=Msur+Mm_a+Mm_b+Ms+Mwater=120.
8kNm/mRestoringmomentsWallstemMwall=wwallu(ltoe+twall/2)=91.
8kNm/mWallbaseMbase=wbaseulbase/2=46.
3kNm/mDesignverticaldeadloadMdead=Wdeadulload=269.
6kNm/mTotalrestoringmomentMrest=Mwall+Mbase+Mdead=407.
8kNm/mCheckbearingpressureDesignverticalliveloadMlive=Wliveulload=12kNm/mTotalmomentforbearingMtotal=Mrest-Mot+Mlive=299kNm/mTotalverticalreactionR=Wtotal=146.
0kN/mDistancetoreactionxbar=Mtotal/R=2048mmEccentricityofreactione=abs((lbase/2)-xbar)=373mmReactionactswithinmiddlethirdofbaseBearingpressureattoeptoe=(R/lbase)-(6uRue/lbase2)=14.
5kN/m2Bearingpressureatheelpheel=(R/lbase)+(6uRue/lbase2)=72.
7kN/m2PASS-MaximumbearingpressureislessthanallowablebearingpressureJobNumber:16060256W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxRETAININGWALLDESIGN(BS8002:1994)TEDDScalculationversion1.
2.
01.
06UltimatelimitstateloadfactorsDeadloadfactorJf_d=1.
4LiveloadfactorJf_l=1.
6EarthandwaterpressurefactorJf_e=1.
4FactoredverticalforcesonwallWallstemwwall_f=Jf_duhstemutwalluJwall=40.
5kN/mWallbasewbase_f=Jf_dulbaseutbaseuJbase=38.
7kN/mAppliedverticalloadWv_f=Jf_duWdead+Jf_luWlive=125.
9kN/mTotalverticalloadWtotal_f=wwall_f+wbase_f+Wv_f=205.
1kN/mFactoredhorizontalat-restforcesonwallSurchargeFsur_f=Jf_luK0uSurchargeuheff=36.
3kN/mMoistbackfillabovewatertableFm_a_f=Jf_eu0.
5uK0uJmu(heff-hwater)2=13.
6kN/mMoistbackfillbelowwatertableFm_b_f=Jf_euK0uJmu(heff-hwater)uhwater=50.
2kN/mSaturatedbackfillFs_f=Jf_eu0.
5uK0u(Js-Jwater)uhwater2=28.
9kN/mWaterFwater_f=Jf_eu0.
5uhwater2uJwater=42.
9kN/mTotalhorizontalloadFtotal_f=Fsur_f+Fm_a_f+Fm_b_f+Fs_f+Fwater_f=171.
9kN/mCalculateproppingforcePassiveresistanceofsoilinfrontofwallFp_f=Jf_eu0.
5uKpucos(Gb)u(dcover+tbase+dds-dexc)2uJmb=6.
1kN/mProppingforceFprop_f=max(Ftotal_f-Fp_f-(Wtotal_f-Jf_luWlive)utan(Gb),0kN/m)Fprop_f=98.
8kN/mFactoredoverturningmomentsSurchargeMsur_f=Fsur_fu(heff-2udds)/2=70kNm/mMoistbackfillabovewatertableMm_a_f=Fm_a_fu(heff+2uhwater-3udds)/3=40kNm/mMoistbackfillbelowwatertableMm_b_f=Fm_b_fu(hwater-2udds)/2=62.
7kNm/mSaturatedbackfillMs_f=Fs_fu(hwater-3udds)/3=24.
1kNm/mWaterMwater_f=Fwater_fu(hwater-3udds)/3=35.
8kNm/mTotaloverturningmomentMot_f=Msur_f+Mm_a_f+Mm_b_f+Ms_f+Mwater_f=232.
5kNm/mRestoringmomentsWallstemMwall_f=wwall_fu(ltoe+twall/2)=128.
5kNm/mWallbaseMbase_f=wbase_fulbase/2=64.
9kNm/mDesignverticalloadMv_f=Wv_fulload=396.
6kNm/mTotalrestoringmomentMrest_f=Mwall_f+Mbase_f+Mv_f=590kNm/mFactoredbearingpressureTotalmomentforbearingMtotal_f=Mrest_f-Mot_f=357.
5kNm/mTotalverticalreactionRf=Wtotal_f=205.
1kN/mDistancetoreactionxbar_f=Mtotal_f/Rf=1743mmEccentricityofreactionef=abs((lbase/2)-xbar_f)=68mmReactionactswithinmiddlethirdofbaseBearingpressureattoeptoe_f=(Rf/lbase)-(6uRfuef/lbase2)=53.
8kN/m2Bearingpressureatheelpheel_f=(Rf/lbase)+(6uRfuef/lbase2)=68.
7kN/m2Rateofchangeofbasereactionrate=(ptoe_f-pheel_f)/lbase=-4.
45kN/m2/mBearingpressureatstem/toepstem_toe_f=max(pheel_f+(rateu(lheel+twall)),0kN/m2)=67.
1kN/m2JobNumber:16060257W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxBearingpressureatmidstempstem_mid_f=max(pheel_f+(rateu(lheel+twall/2)),0kN/m2)=67.
9kN/m2Bearingpressureatstem/heelpstem_heel_f=max(pheel_f+(rateulheel),0kN/m2)=68.
7kN/m2Designofreinforcedconcreteretainingwalltoe(BS8002:1994)MaterialpropertiesCharacteristicstrengthofconcretefcu=40N/mm2Characteristicstrengthofreinforcementfy=500N/mm2BasedetailsMinimumareaofreinforcementk=0.
13%Covertoreinforcementintoectoe=30mmCalculateshearfortoedesignShearfrombearingpressureVtoe_bear=(ptoe_f+pstem_toe_f)ultoe/2=181.
4kN/mShearfromweightofbaseVtoe_wt_base=Jf_duJbaseultoeutbase=34.
7kN/mTotalshearfortoedesignVtoe=Vtoe_bear-Vtoe_wt_base=146.
7kN/mCalculatemomentfortoedesignMomentfrombearingpressureMtoe_bear=(2uptoe_f+pstem_mid_f)u(ltoe+twall/2)2/6=294.
8kNm/mMomentfromweightofbaseMtoe_wt_base=(Jf_duJbaseutbaseu(ltoe+twall/2)2/2)=58.
3kNm/mTotalmomentfortoedesignMtoe=Mtoe_bear-Mtoe_wt_base=236.
5kNm/mChecktoeinbendingWidthoftoeb=1000mm/mDepthofreinforcementdtoe=tbase–ctoe–(Itoe/2)=310.
0mmConstantKtoe=Mtoe/(budtoe2ufcu)=0.
062CompressionreinforcementisnotrequiredLeverarmztoe=min(0.
5+(0.
25-(min(Ktoe,0.
225)/0.
9)),0.
95)udtoeztoe=287mmAreaoftensionreinforcementrequiredAs_toe_des=Mtoe/(0.
87ufyuztoe)=1894mm2/mMinimumareaoftensionreinforcementAs_toe_min=kubutbase=455mm2/mAreaoftensionreinforcementrequiredAs_toe_req=Max(As_toe_des,As_toe_min)=1894mm2/mReinforcementprovided20mmdia.
bars@150mmcentresAreaofreinforcementprovidedAs_toe_prov=2094mm2/mPASS-ReinforcementprovidedattheretainingwalltoeisadequateCheckshearresistanceattoeDesignshearstressvtoe=Vtoe/(budtoe)=0.
473N/mm2JobNumber:16060258W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxAllowableshearstressvadm=min(0.
8u(fcu/1N/mm2),5)u1N/mm2=5.
000N/mm2PASS-DesignshearstressislessthanmaximumshearstressFromBS8110:Part1:1997–Table3.
8Designconcreteshearstressvc_toe=0.
691N/mm2vtoe13%Covertoreinforcementinstemcstem=30mmCovertoreinforcementinwallcwall=30mmFactoredhorizontalat-restforcesonstemSurchargeFs_sur_f=Jf_luK0uSurchargeu(heff-tbase-dds)=33kN/mMoistbackfillabovewatertableFs_m_a_f=0.
5uJf_euK0uJmu(heff-tbase-dds-hsat)2=13.
6kN/mMoistbackfillbelowwatertableFs_m_b_f=Jf_euK0uJmu(heff-tbase-dds-hsat)uhsat=43.
2kN/mSaturatedbackfillFs_s_f=0.
5uJf_euK0u(Js-Jwater)uhsat2=21.
4kN/mWaterFs_water_f=0.
5uJf_euJwateruhsat2=31.
7kN/mCalculateshearforstemdesignShearatbaseofstemVstem=Fs_sur_f+Fs_m_a_f+Fs_m_b_f+Fs_s_f+Fs_water_f-Fprop_f=44.
1kN/mCalculatemomentforstemdesignSurchargeMs_sur=Fs_sur_fu(hstem+tbase)/2=63.
6kNm/mMoistbackfillabovewatertableMs_m_a=Fs_m_a_fu(2uhsat+heff-dds+tbase/2)/3=37.
6kNm/mMoistbackfillbelowwatertableMs_m_b=Fs_m_b_fuhsat/2=46.
4kNm/mSaturatedbackfillMs_s=Fs_s_fuhsat/3=15.
3kNm/mWaterMs_water=Fs_water_fuhsat/3=22.
7kNm/mTotalmomentforstemdesignMstem=Ms_sur+Ms_m_a+Ms_m_b+Ms_s+Ms_water=185.
7kNm/mCheckwallsteminbendingWidthofwallstemb=1000mm/mDepthofreinforcementdstem=twall–cstem–(Istem/2)=310.
0mmConstantKstem=Mstem/(budstem2ufcu)=0.
048JobNumber:16060259W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCompressionreinforcementisnotrequiredLeverarmzstem=min(0.
5+(0.
25-(min(Kstem,0.
225)/0.
9)),0.
95)udstemzstem=292mmAreaoftensionreinforcementrequiredAs_stem_des=Mstem/(0.
87ufyuzstem)=1460mm2/mMinimumareaoftensionreinforcementAs_stem_min=kubutwall=455mm2/mAreaoftensionreinforcementrequiredAs_stem_req=Max(As_stem_des,As_stem_min)=1460mm2/mReinforcementprovided20mmdia.
bars@150mmcentresAreaofreinforcementprovidedAs_stem_prov=2094mm2/mPASS-ReinforcementprovidedattheretainingwallstemisadequateCheckshearresistanceatwallstemDesignshearstressvstem=Vstem/(budstem)=0.
142N/mm2Allowableshearstressvadm=min(0.
8u(fcu/1N/mm2),5)u1N/mm2=5.
000N/mm2PASS-DesignshearstressislessthanmaximumshearstressFromBS8110:Part1:1997–Table3.
8Designconcreteshearstressvc_stem=0.
691N/mm2vstem0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxIndicativeretainingwallreinforcementdiagramToebars-20mmdia.
@150mmcentres-(2094mm2/m)Stembars-20mmdia.
@150mmcentres-(2094mm2/m)RETAININGWALLDEFLECTIONToereinforcementStemreinforcementJobNumber:16060261W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCONCRETEBEAMANALYSISConcretebeamdimensions:-Beamwidthb=1000mmBeamdepthh=350mmCross-sectionareaA=buh=350000mm2MajoraxissecondmomentofareaIxx=buh3/12=3.
57u109mm4fcu=35N/mm2E=20kN/mm2+200ufcu=27.
0kN/mm2RefBS8110:1985:Pt2-Eq17U=UC.
norm=2400kg/m3CONTINUOUSBEAMANALYSIS-INPUTBEAMDETAILSNumberofspans=1MaterialProperties:Modulusofelasticity=27kN/mm2Materialdensity=2400kg/m3SupportConditions:SupportAVertically"Restrained"Rotationally"Restrained"1089Prop14.
572.
74.
210.
211.
724.
525.
0JobNumber:16060262W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxSupportBVertically"Free"Rotationally"Free"SpanDefinitions:Span1Length=3500mmCross-sectionalarea=350000mm2Momentofinertia=3.
57u109mm4LOADINGDETAILSBeamLoads:Load1UDLImposedload4.
2kN/mLoad2PartialVDLDeadload10.
2kN/mat2.
700mto0.
0kN/mat3.
500mLoad3PartialUDLDeadload10.
2kN/mfrom0.
000mto2.
700mLoad4PartialVDLDeadload11.
7kN/mat0.
000mto0.
0kN/mat2.
700mLoad5PartialVDLImposedload24.
5kN/mat0.
000mto0.
0kN/mat2.
700mLOADCOMBINATIONSLoadcombination1Span11.
4uDead+1.
6uImposedLoadcombination2Span11uDead+1uImposedCONTINUOUSBEAMANALYSIS-RESULTSSupportReactions-CombinationSummarySupportAMaxreact=-95.
2kNMinreact=-142.
8kNMaxmom=-119.
0kNmMinmom=-177.
7kNmSupportBMaxreact=0.
0kNMinreact=0.
0kNMaxmom=0.
0kNmMinmom=0.
0kNmBeamMax/Minresults-CombinationSummaryMaximumshear=142.
8kNMinimumshearFmin=0.
0kNMaximummoment=0.
0kNmMinimummoment=-177.
7kNmMaximumdeflection=4.
7mmMinimumdeflection=0.
0mmJobNumber:16060263W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxJobNumber:16060264W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx6.
NoiseVibrationandDustBestconstructionmethodshouldbechosentoreducetheunnecessaryNoise,Vibrationanddust.
Thefollowingtableisaguidancetominimisetheeffectofthesame.
Boreholetest,soilinvestigation,CTMPandCMS.
FullinvestigationsandreportshavetobecarriedoutaheadofbuildingworkstoformalizethebestpracticalmeanstobeusedCONSTRUCTIONMETHODMeasure,NOISEDUSTVIBRATIONInaccordancewiththebestpracticalmeans,tobeusedTominimize,noise,vibrationanddustduringtheconstructionofthebasement,includingtheexcavation,thatislikelytoaffectadjacentresidentialpremisesandschool(ifany)1.
PreparationofsitetofullycontaintheareaBoardingtofrontofhouseenclosingentrance,andwindowskeptinplaceforcompletedurationofconstructionBoardingkeepsnoiseinsidethehouseandkeepshousemorerigidstoppingattenuation,absorbssoundandStopsairbornesoundescapingDustfromdebrisstoredinternallyiscontainedwithinboardeduphousepreventingitfromescapingtoneighboursbeforecollection.
Anyinternalvibrationisfurtherreducedbyadditionalboardingtoabsorbbeforeemittingtoneighbour:astimberabsorbsvibrationbetterthanmetalorglass.
Thehouseisalsomorerigid,stoppingvibrationWindowsretainedandsealedshutduringconstruction,includingfrontdoorandterracedoorskeptclosedAirbornenoiseiscontainedwithindevelopmentAirbornedustiscontainedwithinthedevelopmentWindowsbeingsealedshut(taped)stopsanyrattlingofwindowsoraccentuationofanyvibrationsonsiteHordingandsheetingtocoverroofterrace.
Coveringwithhordingandsheetingrestrictsairbornenoisefromescapingasbestcanbe.
SheetingtoroofterracestopswindowblowingupdustfromexcavationandanydustgeneratedfromHordingandsheetingstopsvibrationasbestispracticable.
JobNumber:16060265W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCONSTRUCTIONMETHODMeasure,NOISEDUSTVIBRATIONworksescapingtovicinity.
RetentionofinternalfloorsandstructureduringexcavationworksKeepingtheinternalfloorsinsituduringworksallowsthehousetoworkasabuffertocontainnoiseandreducesthesiteareatothesmallestvolumereducingtheeffectnoisecanhave.
Dustiscontainedtoasmallerareaandhasseveralfilters(iefloorsandwalls)topassthroughandthusgetstoppedbeforeitcanaffectneighbours,thusreduced.
Retainingtheexistingstructurereducesvibrationbykeepingthehouserigidandsecondlybyhavingamixofmaterialsallwithdifferentattenuationfrequencies;vibrationisabsorbedandnotaccentuated,lastlyfloorsandwallsactasabreakinotherwisecontinuousstructurewhichactsasabuffertostopvibrationcontinuingouttoneighbours.
TemporaryworksandstructureTemporaryworksallowthehousetobekeptrigidandallowforsmallscale,lessnoiseemittingmethodsofconstructiontobeused.
Temporaryworkskeepthehouserigidandsafesostopotherareasofthehousedegeneratingthroughworksandthusdustbeingcreated.
Temporaryworkskeepthehouserigidwhichstopsvibrations.
JobNumber:16060266W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCONSTRUCTIONMETHODMeasure,NOISEDUSTVIBRATION2.
ManagementandhoursofworkingProjectmanagertomanageallworksonsite,memberofConsiderateContractorsSchemeHoursofworkingarerestrictedandstaffsupervisedtousetoolsappropriately.
Noradioonsite.
Smallteamworkingreducingnoise.
Coordinationbetweenworkersensured.
Hoursofworkingarerestrictedandstaffsupervisedtousetoolsappropriatelywithappropriateguardingtopreventdustmigration.
Hoursofworkingarerestrictedandstaffsupervisedtousetoolsappropriatelyandreduceduseofpowertoolstominimizevibration.
3.
ExcavationofbasementNon-percussivetoolsusedforexcavation(iehanddug)Handtoolsarequieter.
MethodchosenreducesneedforanyheavynoisymachineryLessdustgeneratedbyhandtoolsthanfastrepetitivemotordriventools.
VibrationisminimizedbynotusingpercussivetoolsExcavationlimitedto1mrunsandshutteredforreinforcedconcretefoundations.
Eachunderpinisrestrictedto1mlengthscontainingnoiseandamountofworkthatcanbedoneatoncetosmallareathusreducingoverallhubbub.
Methodisquieterthanpilingormachinemethods.
Dustiscontainedwithinshuttering,areaisdampenedwithwatertoallowdiggingandeliminatedust.
Shutteringcontainsanysubsequentvibrationfromexcavationandkeepingsurroundingareasoilintact.
RemovalofspoilAllspoilishandbaggedandstoredinternallybyhandsononoisefromskiporlargerefusearea,removedasperCTMPbysmallSpoilhandbagged,notusingelectricconveyorbelt,andreducingemissionofdust.
Spoilbaggedbyhand(ieshovel)sonomachinerytotransmitvibrationJobNumber:16060267W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCONSTRUCTIONMETHODMeasure,NOISEDUSTVIBRATIONvanandhandloadedRemovalofdebrisBaggeddebrisisstoredinternallyinacoveredareaandremovedbywaitingsmallvanasperCTMPtimedtocauseleastdisruptionDebrisremovedbyhand;dustcontainedwithinrefusesack,sealedshut.
Debrisremovedbyhand,vibrationminimized,inbags.
MixingandpouringofconcreteforunderpinsConcreteismixedonsiteforsmallquantitiesforunderpin,containedwithinthesitefornoiseandforshortperiodoftimeonceunderpinandshutteringformed(ieSeparateactivity)Areasetasideandshutteredoffformixingconcretetocontaindust.
Onlysmallquantitiesmixedattime.
OnlysmallamountsofdryconcreteStoredonsiteininternalareatoavoidunnecessarydust.
Concretemixerputonlevelbaseinclearworkingareatoavoidvibration.
DeliveryofconcreteforfloorreinforcedfloorslabsLargequantitiesarenotmixedonsitebutdeliveredandpumpedbyspecialistlorrytositeinspeedylownoisemethodfromfrontofhousethroughhordingNodustemittedfromdeliveryofliquidconcrete,areaofroadwasheddownbeforeandafterdelivery.
AreacordonedoffasperCTMP(approx.
hour).
Largequantitiesofconcretemixedoffsitetoreducecontinuousvibrationanddeliveredtosite.
JobNumber:16060268W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxAppendixAConstructionSequenceJobNumber:16060269W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx1.
BasementFormationSuggestedMethodStatement1.
1.
Thismethodstatementprovidesanapproachthatwillallowthebasementdesigntobecorrectlyconsideredduringconstruction.
Thestatementalsocontainsproposalsforthetemporarysupporttobeprovidedduringtheworks.
TheContractorisresponsiblefortheworksonsiteandthefinaltemporaryworksmethodologyanddesignonthissiteandanyadjacentsites1.
2.
ThismethodstatementhasbeenwrittenbyaCharteredEngineer.
ThesequencinghasbeendevelopedusingguidancefromASUC(AssociationofSpecialistUnderpinningContractors).
1.
3.
ThismethodhasbeenproducedtoallowforimprovedcostingsandforinclusioninthePartyWallAward.
Finalsiteconditionsneedtheretobeflexibilityinthemethodstatement:ShouldthesitestaffrequirealterationstotheMethodstatementthisisallowedonceanalternativemethodology,ofthechangesisprovided,andanAddendumtothePartyWallAwardwillberequired.
1.
4.
ContactPartyWallSurveyorstoinformthemofanychangestothismethodstatement.
1.
5.
Onthisdevelopment,theapproachis:constructtheunderpinsegmentsthatwillsupportthepermanentsteelworkinsertthenewsteelworkremoveloadfromaboveandplaceitontonewsupportingsteelworkcasttheremainderoftheretainingwallsthatwillformtheperimeterofthebasement.
1.
6.
Temporarypropswillbeprovidedalongtheheightofthepininthetemporarycondition.
Beforethebaseiscastcrosspropsareneeded.
Thebase/groundslabprovidesproppinginthefinalcondition.
Inthetemporarycondition,theedgeoftheslabisbuttressedagainstthesoilinthemiddleoftheproperty.
Alsotheskinfrictionbetweentheconcretebaseandthesoilprovidesfurtherresistance.
Thecentralsoilmassistoberemovedinportions(thirdsbutnogreaterthan8m)andcrossproppingsubsequentlyaddedasthecentralsoilassisremoved1.
7.
Agroundinvestigationhasbeenundertaken.
Thesoilpresentismadegroundovergravels,overclaywithdecreasingsandycontentandincreaseddensityasthedepthincreasedwithaccordedwithotherinvestigationsmadeinthearea.
1.
8.
Thebearingpressureshavebeenlimitedto100kN/m21.
9.
Thewatertablewasencounteredat8.
9mBGLandhenceonthissiteitwillnotbeanissueduringtheconstruction.
1.
10.
Thestructuralwaterproofer(notCroft)mustcommentontheproposeddesignandensurethatheissatisfiedthattheproposalswillprovideadequatewaterproofing.
1.
11.
Provideengineerswithconcretemix,supplier,deliveryandplacementmethodstwoweekspriortothefirstpour.
SitemixingofconcreteshouldnotbeemployedapartfrominsmallJobNumber:16060270W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxsections(lessthan1m3).
Thecontractormustprovideamethodonhowtoachievesitemixingtothecorrectspecification.
Thecontractormustundertaketoolboxtalkswithstafftoensuresitequalityismaintained.
2.
EnablingWorks2.
11.
Thesiteistobehoardedwithplyboardsheets,atleast2.
2mhigh,topreventunauthorisedpublicaccess.
2.
12.
Licencesforskipsandconveyorsshouldbepostedonthehoarding.
2.
13.
Provideprotectiontopublicwhereconveyorextendsoverfootpath.
Dependingontherequirementsofthelocalauthority,constructaplywoodbulkheadoverthepavement.
Hoardingtohaveaplywoodroofcoveringoverthefootpath,night-lightsandsafetynotices.
2.
14.
Dewater:Nosignificantdewateringisexpected.
Localisedremovalofwatermayberequiredtodealwithrainfromperchedwaterorlocalisedwater.
Thisistobedealtwithbylocalisedpumping.
Typicallyachievedbyasmallsumppumpinabucket.
2.
15.
Oncommencementofconstruction,thecontractorwilldeterminethefoundationtype,widthanddepth.
Anydiscrepancieswillbereportedtothestructuralengineerinorderthatthedetaileddesignmaybemodifiedasnecessary.
3.
BasementSequencing3.
11.
Beginbyplacingcantileveredwalls12notedonplans.
(CantileveredwallstobeplacedinaccordancewithSection4.
)3.
12.
Needleandpropthefirstfloor/wallsover.
3.
13.
Insertsteeloverandsitoncantileveredwalls.
3.
13.
1.
Beamsover6mtobejackedonsitetoreducedeflectionsoffloors.
3.
13.
2.
Drypacktosteelwork.
Ensureaminimumof24hoursfromcastingcantileveredwallstodry-packing.
Groutcolumnbases3.
14.
Excavatelightwelltofrontofpropertydownto600mmbelowexternalgroundlevel.
3.
15.
Excavatefirstfrontcorneroflightwell.
(FollowmethodologyinSection4)JobNumber:16060271W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx3.
16.
Excavatesecondfrontcorneroflightwell.
(FollowmethodologyinSection4)3.
17.
Continueexcavatingsectionpinstoformfrontlightwell.
(FollowmethodologyinSection4)3.
18.
Placecantileveredretainingwalltotheleftsideoffrontopening.
After48hoursplacecantileveredretainingwalltotherightsideoffrontopening.
3.
19.
Needleandpropfrontwall.
InsertsupportFigure17Exampleofneedlingtoexistingwall3.
20.
Excavateoutfirst1maroundfrontopening,propflooranderectconveyor.
3.
21.
Continuecantileveredwallformationaroundperimeterofbasementfollowingthenumberingsequenceonthedrawings.
3.
21.
1.
Excavationforthenextnumberedsequentialsectionsofunderpinningshallnotcommenceuntilatleast8hoursafterdrypackingofpreviousworks.
Excavationofadjacentpintonotcommenceuntil48hoursafterdrypacking.
(24hourspossibleduetoinclusionofConbextra100cementacceleratortodrypackmix).
Nomorethan3.
21.
2.
Floorovertobeproppedasexcavationprogresses.
Steelworktosupportfloortobeinsertedasworksprogress.
3.
22.
Excavateandcastfloorslab3.
22.
1.
Excavate1/3ofthemiddlesectionofbasementfloor.
Asexcavationproceeds,placeSlimShorepropsatamaximumof2.
5mc/cacrossthebasement.
Locatepropsatathirdoftheheightofthewall.
JobNumber:16060272W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx3.
22.
2.
Continueexcavatingthenext1/3andpropthenrepeatforthefinal1/3.
3.
22.
3.
Placebelow-slabdrainage.
Croftrecommendsthatalldrainageisencasedinconcretebelowtheslabandcastmonolithicallywiththeslab.
Placingdrainageonpeashinglebelowtheslaballowsgreaterpenetrationforwateringress.
3.
22.
4.
Placereinforcementforbasementslab.
3.
22.
5.
BuildingControlOfficerandEngineeraretobeinformedfiveworkingdaysbeforereinforcementisreadyandinvitedforinspection.
3.
22.
6.
Onceinspected,pourconcrete.
3.
23.
Providestructuretogroundfloorandwaterproofingtoretainingwallsasrequired.
Itisrecommendedtoleave3-4weeksbetweencompletionofthebasementandinstallingdrainedcavity.
Thisperiodshouldbeusedtolocateandfillanylocalisedleakageofthebasement4.
UnderpinningandCantileveredWalls4.
11.
Priortoinstallationofnewstructuralbeamsinthesuperstructure,thecontractormayundertakethelocalexplorationofspecificareasinthesuperstructure.
Thiswillconfirmtheexactformandlocationofthetemporaryworksthatarerequired.
Thepermanentstructuralworkcanthenbeundertakenwhilstensuringthatthefullintegrityofthestructureaboveismaintained.
4.
12.
Provideproppingtofloorwherenecessary.
4.
13.
Excavatefirstsectionofretainingwall(nomorethan1000mmwide).
Whereexcavationisgreaterthan1.
2mdeep,providetemporaryproppingtosidesofexcavationtopreventearthcollapse(HealthandSafety).
A1000mmwidthwallhasalowerriskofcollapsetotheheelface.
4.
14.
Excavationofpinsinvolvesworkinginconfinedspacesandthefollowingmeasuresshouldbeapplied:JobNumber:16060273W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxoOperativesmustwearaharnessandtheremustbeawinchabovetheexcavation.
oAnattendantmustbepresentatalltimes,atgroundlevel,whileexcavationisoccupied.
oArescueplanmustbeproducedpriortotheworksaswellasatask-specificriskandmethodstatement.
oWorkingintheconfinedspaceshouldrequireapermittowork.
Figure18–SchematicPlanviewofsoilproppingFigure19ProppingexamplesJobNumber:16060274W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxFigure20ExamplesofexcavationsofpinsFigure21Examplesofcompletedwallsandbackproppingtocentralsoilmass4.
15.
Backproppingofrearface:Rearfacetobeproppedinthetemporaryconditionswithaminimumof2trenchsheets.
Trenchsheetsaretoextendoverentireheightofexcavation.
Trenchsheetscanbeplacedinshortsectionsastheexcavationprogresses.
JobNumber:16060275W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxFigure22Exampleoftrenchsheetbackpropping4.
15.
1.
Ifthegroundisstable,trenchsheetscanberemovedasthewallreinforcementisplacedandtheshutteringisconstructed.
4.
15.
2.
Wheretrenchsheetsareleftin,slightoverspillmayoccurpasttheneighboursboundarywallline.
WherethisslightoverspillisnotallowedbythePartyWallSurveyorsthencementparticleboardshouldbeusedasnotedbelow.
JobNumber:16060276W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx4.
15.
3.
Wheresoftspotsareencountered,leaveintrenchsheetsoralternativelybackpropwithprecastlintelsorsacrificialboards.
Ifthesoilsupporttotheendsofthelintelsisinsufficient,thenbracetheendsofthePClintelswith150x150C24timbersandpropwithAcrowsdiagonallybacktotheground.
4.
15.
4.
Wherevoidsarepresentbehindthelintelsortrenchsheeting,groutvoidsbehindsacrificialpropping.
Grouttobe3:1sand/cementpackedintovoids.
4.
15.
5.
Priortocasting,placelayerofDPMbetweentrenchsheeting(orPClintels)andnewconcrete.
Thelintelsaretobecutintothesoilby150mmeithersideofthepin.
Asitestockofaminimumof10lintelsshouldbepresenttopreventdelaysduetoordering.
4.
16.
Ifcutfaceisnotstraight,orsacrificialboardsnotedpreviouslyhavebeenused,placea15mmcementparticleboardbetweensacrificialsheetsoragainstthesoilpriortocasting.
Cementparticleboardistolineupwiththeadjacentowner'sfaceofwall.
Themethodadopted,topreventlocalisedcollapseofthesoil,istoinstalltheseprogressively,oneatatime.
Cementparticleboardmustbeusedinanyconditionwhereoverspillontotheadjacentowner'slandispossible.
4.
17.
Excavatebase.
Ifsoiloverisunstable,proptopwithPClintelandsacrificialprop.
4.
18.
Visuallyinspectthefootingsandprovideproppingtolocalbrickwork.
IfnecessaryinstallsacrificialAcrow,orpitprops,andcastintotheretainingwall.
4.
19.
Clearundersideofexistingfooting.
4.
20.
LocalAuthorityinspectiontobecarriedoutforapprovalofexcavationbase.
4.
21.
Placereinforcementforretainingwallbaseandstem.
DriveH16BarsU-barsintosoilalongcentrelineofstemtoactassheartiestoadjacentwallunderpin.
4.
22.
Sitesupervisortoinspectandsignoffworksbeforeproceedingtonextstage.
4.
22.
1.
Forpins1,3and5,informtheengineerfivedaysbeforethereinforcementisready,toallowforinspectionofthereinforcementpriortocasting.
4.
23.
Castbase.
Onshortstemsitispossibletocastbaseandwallatthesametime.
Itisessentialthatpokers/vibratorsareusedtocompactconcrete.
4.
24.
ConcreteTesting:4.
24.
1.
Forfirst3pinstake4cubesandtestat7daysthenat14daysandinformengineerofresults.
Testlastcubeat28days.
Ifcubetestresultsarelowthenactionintoconcretespecificationandplacementmethodmustbeconsidered.
JobNumber:16060277W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx4.
24.
2.
Ifresultsaregoodfromfirstthreepins,thenfromthe4thpinonwardstake2cubesofconcretefromeverythirdpinandstorefortesting.
Testoneat28days.
Ifresultislow,testsecondcube.
Provideresultstoclientanddesignteamonrequestorifvaluesarebelowthoserequired.
4.
24.
3.
Arecordofdatesfortheconcretepouringofeachpinmustbekeptonsite.
4.
24.
4.
Thelocationofwherecubesweretakenandtheirreferencenumbermustberecorded.
4.
25.
Horizontaltemporaryproptobaseofwalltobeinserted.
Alternativelycastbaseagainstsoil.
4.
26.
Placeshutteringandpourconcreteforretainingwall.
Stopaminimumof75mmfromtheundersideofexistingfooting.
Itisessentialthatpokers/vibratorsareused,hittingshuttersisnotconsideredadequate.
4.
27.
24hoursafterpouringtheconcretepin,thegapshallbefilledusingadry-packmortar.
Ramindry-packbetweenthetopoftheretainingwallandexistingmasonry.
4.
27.
1.
Ifgapisgreaterthan120mm,placealineofengineeringbrickstothetopofthewall.
Drypackfromtheengineeringbrickstoexistingmasonry.
4.
28.
After24hours,thetemporarywallshutterscanberemoved.
4.
29.
Trimbackexistingmasonrycorbelandconcreteoninternalface.
4.
30.
Sitesupervisortoinspectandsignoffforproceedingtothenextstage.
Arecordwillbekeptofthesequenceofconstruction,whichwillbeinstrictaccordancewithrecognisedindustryprocedures.
5.
FloorSupportTimberFloor5.
11.
Thetimberfloorwillremaininsituandbesupportedbyaseriesofsteelbeams,toprovideopenareasinthebasement.
5.
12.
Position100x100mmtemporarytimberbeams,lightlypacked,toundersideofjoistseithersideofexistingsleeperwallandsupportwithverticalAcrowprops@750centres.
Removesleeperwallsandinsertsteelbeamsasareplacement.
Steelbeamstobearontoconcretepadstonesbuiltintothemasonrywalls(refertoStructuralEngineer'sdetailsforpadstoneandbeamsizes)JobNumber:16060278W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx5.
13.
Dismantlepropsandremovetimberplatesoncompletionofinstallationofpermanentsteelbeams.
ConcreteGroundbearingslabs5.
14.
Thesupportoftheexistingconcretefloorwillbeundertakeninconjunctionwiththeunderpinningprocess.
Twooppositepinsareconstructedandallowedtocureasdescribedelsewhere.
5.
15.
LocallypropconcretefloorswithAcrowsat2mcentreswithtimbersbetween.
Iftheundersideisfoundbeinpoorconditionthentemporaryboardingandpropsaretobeintroduced.
5.
16.
Insertsteelworkanddrypacktoundersideoffloor5.
17.
Betweensteelwork,place215widex65dpPClintelsatamaximumspacingof600mm5.
18.
Ifnecessary,brickupto50mmbelowtheundersideofthefloor5.
19.
Drypackbetweenlintel/brickworktoundersideofslab.
5.
20.
Removeprops5.
21.
Thisprocessistocontinueonepinwidthatatime.
6.
Supportingexistingwallsabovebasementexcavation6.
11.
Wheresteelbeamsneedtobeinstalleddirectlyunderload-bearingwalls,temporaryworkswillberequiredtoenablethisinstallation.
Supportcomprisesthetemporaryinstallationofsteelneedlebeamsathighlevel,supportedonverticalprops.
Thiswillenablesaferemovalofbrickworkbelowandinstallationofthenewbeamsandcolumns.
6.
11.
1.
Theconditionofthebrickworkmustbeinspectedbytheforemantodetermineitsconditionandtoassessthecentresofneedles.
Theforemanmustinspectupstairstoconsiderwhereloadsaregreatest.
Pointloadsbetweenwindowsshouldbegivengreaterconsideration.
6.
11.
2.
Needlesaretobespacedtopreventthebrickworkabove'sawtoothing'.
Wherebrickworkisgood,needlesmustbeplacedatamaximumof1100mmcenters.
LighterneedlesorStrongboysshouldbeplacedattightercentresunderdoorthresholdsJobNumber:16060279W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx6.
12.
Propsaretobeplacedonsleepersonfirmgroundor,ifnecessary,temporaryfootingswillbecast.
6.
13.
Oncethepropsarefullytightened,thebrickworkwillbebrokenoutcarefullybyhand.
Allnecessaryplatformsandcrashdeckswillbeprovidedduringthisoperation.
6.
14.
Deckingandsupportplatformstoenablehandlingofsteelbeamsandcolumnswillbeprovidedasrequired.
6.
15.
Oncefullstructuralbearingisprovidedviabeamsandcolumnsdowntothenewbasementfloorlevel,thetemporaryworkswillberedundantandcanbesafelyremoved.
6.
16.
Anyvoidsbetweenthetopofthepermanentsteelbeamsandtheundersideoftheexistingwallswillbepackedoutasnecessary.
Voidswillbedrypackedwitha1:3(cement:sharpsand)drypacklayer,betweenthetopofthesteelandundersideofbrickworkabove.
6.
17.
Anyvoidsinthebrickworkleftafterremovalofneedlebeamscanatthispointberepairedbybrickingupand/ordrypacking,toensurecontinuityofthestructuralfabric.
7.
Approval7.
11.
BuildingControlOfficer/ApprovedInspectortoinspectpinbasesandreinforcementpriortocastingconcrete.
7.
12.
Contractortokeeplistofdatesofpinsinspectedandcast.
7.
13.
Onemonthaftertheworkiscompleted,thecontractoristocontactAdjoiningPartyWallSurveyortoattendsiteandcompletefinalconditionsurveyandtosignoffworks.
JobNumber:16060280W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docx8.
BasementTemporaryWorksDesignLateralProppingThiscalculationhasbeenprovidedforthetrenchsheetandpropdesignofstandardunderpinsinthetemporarycondition.
Therearegapsleftbetweenthesheetingandassuchnowaterpressurewilloccur.
Anywaterpresentwillflowthroughthegapsbetweenthesheetingandwillberequiredtobepumpedout.
Trenchsheetsshouldbeplacedatregularcentrestodealwiththeground.
Itisexpectedthatthesoilbetweenthetrenchsheetingwillarch.
Loosersoilwillrequiretightercentres.
Itistypicalforunderpinstobeplacedat1200c/cinthisconditionthehighestloadonatrenchsheetiswhen2No.
strenchsheetsareused.
Itisforthisdesignthatthesecalculationshavebeenprovided.
Soilandgroundconditionsarevariable.
Typicallyonefindsthat,inthetemporarycondition,claysaremorestableandtheCu(cohesive)valuesinclayreducetheriskofcollapse.
Itisthiscohesivenaturethatallowsclaystobecutintoaverticalslope.
Forthesecalculations,weaksandandgravelshavebeenassumed.
Thesoilpropertiesare:JobNumber:16060281W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxTrenchSheetDesignSoilDepthDsoil=3500mmSurchargesur=10kN/m2SoilDensityJ=20kN/m3AngleofFrictionI=25qka=(1-sin(I))/(1+sin(I))=0.
406kp=1/ka=2.
464Soilpressurebottomsoil=ka*J*Dsoil=21.
916kN/m2Surchargepressuresurcharge=sur*ka=4.
059kN/m2JobNumber:16060282W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxSxx=15.
9cm3py=275N/mm2Ixx=26.
9cm4A=(1m*32.
9kg/m2)/(7750kg/m3)=4245.
161mm2JobNumber:16060283W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxCONTINUOUSBEAMANALYSIS-INPUTBEAMDETAILSNumberofspans=3MaterialProperties:Modulusofelasticity=205kN/mm2Materialdensity=7860kg/m3SupportConditions:SupportAVertically"Restrained"Rotationally"Free"SupportBVertically"Restrained"Rotationally"Free"SupportCVertically"Restrained"Rotationally"Free"SupportDVertically"Free"Rotationally"Free"SpanDefinitions:Span1Length=1000mmCross-sectionalarea=4245mm2Momentofinertia=269.
u103mm4Span2Length=1600mmCross-sectionalarea=4245mm2Momentofinertia=269.
u103mm4JobNumber:16060284W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxSpan3Length=1000mmCross-sectionalarea=4245mm2Momentofinertia=269.
u103mm4LOADINGDETAILSBeamLoads:Load1UDLDeadload4.
1kN/mLoad2VDLDeadload21.
9kN/mto0.
0kN/mLOADCOMBINATIONSLoadcombination1Span11.
4uDeadSpan21.
4uDeadSpan31.
4uDeadCONTINUOUSBEAMANALYSIS-RESULTSSupportReactions-CombinationSummarySupportAMaxreact=-12.
3kNMinreact=-12.
3kNMaxmom=0.
0kNmMinmom=0.
0kNmSupportBMaxreact=-38.
5kNMinreact=-38.
5kNMaxmom=0.
0kNmMinmom=0.
0kNmSupportCMaxreact=-24.
8kNMinreact=-24.
8kNMaxmom=0.
0kNmMinmom=0.
0kNmSupportDMaxreact=0.
0kNMinreact=0.
0kNMaxmom=0.
0kNmMinmom=0.
0kNmBeamMax/Minresults-CombinationSummaryMaximumshear=18.
8kNMinimumshearFmin=-19.
8kNMaximummoment=2.
4kNmMinimummoment=-4.
4kNmMaximumdeflection=17.
1mmMinimumdeflection=-0.
1mmNumberofsheetsNos=3MomentM_allowable=Sxx*py*Nos=13.
118kNmDeflectionD=/Nos=5.
699mmAcroLoadAcro=Rmax_B/2=-19.
272kNJobNumber:16060285W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxAcrowPropsAorBareacceptableplaced0.
5mfromtop,middleand1mfrombottomCrossPropsPropsshouldbeplacedathirdupthewallmeasuredfromthebottomslab.
JobNumber:16060286W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxSurchargesur=10kN/m2SoilDensityJ=20kN/m3AngleofFrictionI=25qSoilDepthDsoil=3000mmka=(1-sin(I))/(1+sin(I))=0.
406kp=1/ka=2.
4641-sin(I)=0.
577Soilforcebottomsoilforce=ka*J*Dsoil*Dsoil/2=36.
527kN/mSurchargeForceSurchargeforce=ka*sur*Dsoil=12.
176kN/mPlacePropseveryotherpinspacing=2mPropforcePropforce=spacing*(soilforce+Surchargeforce)=97.
406kNJobNumber:16060287W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxFigure23MabeyMass25LoadChartJobNumber:16060288W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxFigure24MabeyMass50LoadChartProvideMabeyMass50at2mCentresat1/3theheightofthewall.
JobNumber:16060289W:\ProjectFile\ProjectStorage\2016\160602-25OldChurchStreet\2.
0.
Calcs\CMS\cmscroft\25OldChurchStreetSubterraneanConstructionMethodStatement.
docxAppendixB–StructuralPlans&DetailsStructuralDrawingsPlans1:100StructuralSections1:50