混凝土外約束拉應(yīng)力計(jì)算書

混凝土外約束拉應(yīng)力計(jì)算書計(jì)算依據(jù)：1、《大體積混凝土施工標(biāo)準(zhǔn)》GB50496-20182、《建筑施工計(jì)算手冊(cè)》江正榮編著一、混凝土外約束拉應(yīng)力第1層保溫層厚度δ1(m)0.039第1層保溫材料導(dǎo)熱系數(shù)λ1[W/(m·K)]0.06實(shí)測(cè)日期t1(d)3實(shí)測(cè)溫度T1(°C)36.5松弛系數(shù)H1(t1)0.186實(shí)測(cè)日期t2(d)6實(shí)測(cè)溫度T2(°C)40.1松弛系數(shù)H2(t2)0.208實(shí)測(cè)日期t3(d)9實(shí)測(cè)溫度T3(°C)40.8松弛系數(shù)H3(t3)0.214實(shí)測(cè)日期t4(d)12實(shí)測(cè)溫度T4(°C)38.3松弛系數(shù)H4(t4)0.215實(shí)測(cè)日期t5(d)15實(shí)測(cè)溫度T5(°C)35.7松弛系數(shù)H5(t5)0.233實(shí)測(cè)日期t6(d)18實(shí)測(cè)溫度T6(°C)33.2松弛系數(shù)H6(t6)0.252實(shí)測(cè)日期t7(d)21實(shí)測(cè)溫度T7(°C)31.5松弛系數(shù)H7(t7)0.301實(shí)測(cè)日期t8(d)24實(shí)測(cè)溫度T8(°C)30.4松弛系數(shù)H8(t8)0.524實(shí)測(cè)日期t9(d)27實(shí)測(cè)溫度T9(°C)29.5松弛系數(shù)H9(t9)0.57實(shí)測(cè)日期t10(d)30實(shí)測(cè)溫度T10(°C)29.3松弛系數(shù)H10(t10)1固體在空氣中的放熱系數(shù)βu[W/(m2·K)]164.934混凝土的導(dǎo)熱系數(shù)λ0[W/(m·K)]2.33混凝土澆筑體的長(zhǎng)度L(m)60混凝土澆筑體的實(shí)際厚度h(m)2.4外約束介質(zhì)水平變形剛度CX(10-2N/mm3)100水泥品種修正系數(shù)M11水泥細(xì)度修正系數(shù)M21.35水膠比修正系數(shù)M31.15膠漿量修正系數(shù)M41.45養(yǎng)護(hù)時(shí)間修正系數(shù)M50.93環(huán)境相對(duì)濕度修正系數(shù)M60.77水力半徑的倒數(shù)修正系數(shù)M71ESFS/ECFC修正系數(shù)M80.55減水劑修正系數(shù)M91.3粉煤灰摻量修正系數(shù)M101礦粉摻量修正系數(shù)M111.12粉煤灰摻量對(duì)彈性模量調(diào)整修正系數(shù)β11礦渣粉摻量對(duì)彈性模量調(diào)整修正系數(shù)β21.04系數(shù)φ0.091、各齡期混凝土彈性模量Ei(3)=βE0(1-e-φt)=β1β2E0(1-e-φt)=1×1.04×3×104×(1-2.718-0.09×3)=7383N/mm2同理：Ei(6)=13018N/mm2，Ei(9)=17320N/mm2，Ei(12)=20605N/mm2，Ei(15)=23112N/mm2，Ei(18)=25026N/mm2，Ei(21)=26487N/mm2，Ei(24)=27602N/mm2，Ei(27)=28453N/mm2，Ei(30)=29103N/mm22、各齡期混凝土澆筑體綜合降溫差的增量εy(3)=εy0(1-e-0.01t)·M1·M2·M3…M11=4×10-4×(1-2.718-0.01×3)×1×1.35×1.15×1.45×0.93×0.77×1×0.55×1.3×1×1.12=1.526×10-53天的混凝土的收縮當(dāng)量溫度：Ty(3)=εy(t)/α=1.526×10-5/1.0×10-5=1.53°C同理：εy(6)=3.007×10-5，Ty(6)=3.01°C，εy(9)=4.444×10-5，Ty(9)=4.44°C，εy(12)=5.839×10-5，Ty(12)=5.84°C，εy(15)=7.193×10-5，Ty(15)=7.19°C，εy(18)=8.506×10-5，Ty(18)=8.51°C，εy(21)=9.781×10-5，Ty(21)=9.78°C，εy(24)=11.018×10-5，Ty(24)=11.02°C，εy(27)=12.218×10-5，Ty(27)=12.22°C，εy(30)=13.383×10-5，Ty(30)=13.38°CΔT2i(6)=(T2-T1)+(Ty(6)-Ty(3))=(36.5-40.1)+(3.007-1.526)=-2.119°C同理：ΔT2i(9)=0.737°C，ΔT2i(12)=3.895°C，ΔT2i(15)=3.954°C，ΔT2i(18)=3.814°C，ΔT2i(21)=2.975°C，ΔT2i(24)=2.337°C，ΔT2i(27)=2.1°C，ΔT2i(30)=1.365°C3、各齡期外約束系數(shù)保溫層總熱阻：RS=Σ(δi/λi)+1/βu=(0.039/0.06)+1/164.934=0.656(m2·K)/W保溫層總放熱系數(shù)：βS=1/RS=1/0.656=1.524W/(m2·K)保溫層相當(dāng)于混凝土的虛擬厚度：h'=λ0/βS=2.33/1.524=1.529mRi(6)=1-1/cosh[(CX/HE(6))0.5×L/2]=1-1/cosh[(100×10-2/((1.529+2.4)×103×13018))0.5×60×103/2]=0.96986同理：Ri(9)=0.94737，Ri(12)=0.92882，Ri(15)=0.91431，Ri(18)=0.90317，Ri(21)=0.89466，Ri(24)=0.88818，Ri(27)=0.88326，Ri(30)=0.87954、各齡期外約束拉應(yīng)力σx(6)=αΔT2i(6)×Ei(6)×Hi(6)×Ri(6)/(1-μ)=1×10-5×-2.119×13018×0.186×0.96986/(1-0.15)=-0.058544MPa同理：σx(9)=0.029601MPa，σx(12)=0.187662MPa，σx(15)=0.211317MPa，σx(18)=0.236277MPa，σx(21)=0.208985MPa，σx(24)=0.202887MPa，σx(27)=0.325419MPa，σx(30)=0.234293MPa5、外約束拉應(yīng)力σx=σx(6)+σx(9)+σx(12)+σx(15)+σx(18)+σx(21)+σx(24)+σx(27)+σx(30)=-0.058544+0.029601+0.187662+0.211317+0.236277+0.208985+0.202887+0.325419+0.234293=1.577899M