路基排水沟、边沟水力计算书

-至高速公路粤境连平至从化段D1合同段路基排水设施水力计算书台截水沟和截水沟等排水设施来排除和拦截路界围外的雨水。现按照"公路排水设计规"JTJ018-97的规定，通过计算设计径流量反算各种排水设施各型号的最大排水距离(即出水口距离)和面积，为确定各路段各种排水设施型号的选取提供参历时之和。设降雨历时为3min。拦水路缘石与路肩铺面构成的浅三角型过水断面的泄水能力为：Qc＝0.377×h8/3×I1/2/〔i×n〕＝0.377×0.058/3×I0.5/〔0.02×0.013〕h2)汇水面积和径流系数F=l×19.75×10-6km2取径流系数Ψ=0.95。-3)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路面和路肩外表排水按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，5年设计重现期时的重现期5,10转换系数为c=1.0,60min降雨强度转换系数为c=0.5，3min降雨历时转换p605q=1.0×1.40×2.8=3.92mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.95×3.92×l×19.75×10-6m3/s6〕拦水缘石最大排水距离的计算Qc＝0.377×h8/3×I1/2/〔i×n〕＝0.377×0.058/3×0.0050.5/h0.035>16.67×0.95×3.92×l×19.75×10-6为l＝0.035/〔16.67×0.95×3.92×19.75×10-6〕＝28.55m-由表查得地表粗度系数为m=0.013,路面横坡为i=0.02,坡面流长度为1sLs=19.75m，可计算得到坡面汇流历时按式v=20i0.6得v＝20×0.0050.6=0.83m/s，g再按式t=l/(60×v)=28.55/(60×0.83)=0.57min2it=tt=1.909+0.57=2.48min<3min展计算，并对汇流历时进展检验，结果列于表1。泄水能力(m泄水能力(m3/s)0.0350.0410.0490.0600.0700.0780.0850.0920.0982.482.462.442.422.402.392.382.382.372834637075800.5%0.7%0%1.5%2.0%2.5%3.0%3.5%4.0%知，拦水路缘石的最大排水距离随着路线纵坡的加大而增大，汇流历时均小于3min。因此，现拟定:当路线纵坡为0.5%~0.7%时，出水口间距设为30m；当路线纵坡为0.7%~1.0%时，出水口间距设为35m；当路线纵坡为1.0%~1.5%时，出水口间距设为40m；-当路线纵坡为1.5%~2.0%时，出水口间距设为50m；当路线纵坡为大于2.0%时，出水口间距设为60m。的排水沟。由急流槽槽底纵坡〔即路堤边坡坡度i=1:1.5〕i=66.7％，可计算ggmm流槽的过水能力v=n-1R2/3I1/2=0.015-10.0892/30.6671/2=10.85m/s设路基填土为7米高，则急流槽长度l为10.5m，可得到急流槽的沟管汇t=l/(60×v)=10.5/(60×10.85)=0.016min3影响可忽略不计。因此，降雨历时仍为3min时，暴雨强度为3.92mm/min。因此，根据"公路排水设计规"JTJ018-97，设计径流量仍为Q=16.67ΨqF=16.67×0.85×3.92×l×19.75×10-6m3/s当急流槽沟底纵坡为66.7％时，矩形急流槽的泄水能力为Qc＝Av=0.064×10.85=0.694m3/s2。-设计径流设计径流量(m3/s)0.0330.0380.0440.0550.066303560由表2可知，急流槽泄水能力远大于按各种间距设置出水口时的设计径流面汇流历时与沟的沟管汇流历时之和。设降雨历时为10min。断面面积A为0.288m2，过水断面湿周ρ为1.56m，水力半径R＝A/ρ=0.185m，当排水沟纵坡0为.3%时，则v=n-1R2/3I1/2=0.015-10.1852/30.0031/2=1.18m/s2)汇水面积和径流系数局部组成：一局部为路面围的汇水面积F＝19.75×l，径流系数取Ψ＝0.95；11另外一局部为路堤坡面的汇水面积F＝(7×1.5+1)×l=11.5×l(7为边坡高度，22积F=31.25×l×10-6km2取径流系数Ψ=(0.95×F+0.65×F)/(31.25×l)=0.842-3)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路界坡面排水设计重按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，15年设计重现期时的重现5,10期转换系数为c=1.27,60min降雨强度转换系数为c=0.5，10min降雨历时p605q=1.27×1.0×2.8=3.556mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.84×3.556×31.25×l×10-6m3/sQc＝Av=0.288×1.18=0.341m3/s0.341>16.67×0.84×3.556×l×31.25×10-6为l＝0.341/〔16.67×0.84×3.556×31.25×10-6〕＝219m设-拦水缘石的计算可得，路面汇流历时为2.48min；路堤边坡的地表粗度系数为m=0.4，坡面横坡为i=0.667，坡面流长度为Ls=13.62m〔填土高度7m，1s因此，取t＝3.51min1按式v=n-1R2/3I1/2得v＝0.015-10.1852/30.0031/2=1.18m/s再按式t=l/(60×v)=219/(60×1.18)=3.09min2t=tt=3.51+3.09=6.6min<10min再假设降雨历时为7min，通过插得出降雨历时转换系数c=1.15，暴雨强t度为q=1.27×1.15×2.8=4.089mm/min，通过以上过程的计算得到，当沟lm当沟底纵坡为其它数值时，按照上述计算过程对PSG－1型最大排水距离进展计算，并对汇流历时进展检验，结果列于表3。泄水能力(m泄水能力(m3/s)0.3410.4400.5210.6230.7620.8800.9842462913484264925506.196.196.196.196.196.196.190.3%0.5%0.7%.0%1.5%2.0%2.5%-1.0781.1651.2456.196.196.19603651696表4不同沟底纵坡PSG－2(80*60)最大排水距离(降雨历时为8min)泄泄水能力(m3/s)0.5080.6560.7760.9281.1361.3121.4671.6071.7361.8567.257.257.257.257.257.257.257.257.257.252973834545426647678579390.3%0.5%0.7%1.0%1.5%2.0%2.5%3.0％3.5％4.0％表5不同沟底纵坡PSG－3(80*80)最大排水距离(降雨历时为9min)泄水能泄水能力(m3/s)0.7340.9481.1221.3411.6421.8962.1202.3222.5082.6818.738.738.738.738.738.738.738.738.738.734495806878210.3%0.5%0.7%1.0%1.5%2.0%2.5%3.0％3.5％4.0％2-沟底纵坡PSG最大排水距离PSG-2PSG-30.3%~0.5%2974490.5%~0.7%2463835800.7%~1.0%2914546871.0%~1.5%3485428211.5%~2.0%4266642.0%~2.5%4927672.5%~3.0％5508573.0％~3.5％6039393.5％~4.0％651>4.0%696108416414．边沟最大排水距离的计算BG－A型历时之和。设降雨历时为5min。.08＝0.333m2，水力半径R＝0.52.08=0.143m，当v=n-1R2/3I1/2=0.05-10.1432/30.0031/2=0.30m/s2)汇水面积和径流系数围的汇水面积F＝19.75×l，径流系数取Ψ＝0.95；另外一局部为路堑坡面1的汇水面积F＝(8×1.0+2.6+1.5)×l=12.1×l(8为第一级边坡高度，1.0为第2数取Ψ＝0.65；则，总的汇水面积-F=31.85×l×10-6km2拟定坡面为细粒土坡面，取径流系数Ψ=(0.95×F+0.65×F)/(31.85×l)=0.83623)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路界坡面排水设计重现按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，15年设计重现期时的重现期转换5,10系数为c=1.27，60min降雨强度转换系数为c=0.5，5min降雨历时转换系p605q=1.27×1.25×2.8=4.445mm/min5〕BG－A型边沟最大排水距离计算根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.836×4.445×31.85×l×10-6m3/sQc＝Av=0.333×0.3=0.1m3/s0.1>16.67×0.836×4.445×31.85×l×10-6l＝0.1/〔16.67×0.836×4.445×31.85×10-6〕＝51m历时假设-1坡面横坡为i=1.0，坡高8m，坡面流长度为Ls=(11.3+2.6+1.5)=15.4m(11.3s因此，取t＝3.38min1按式v=n-1R2/3I1/2，得v＝0.05-10.1432/30.0031/2=0.3m/s再按式t=l/(60×v)=51/(60×0.3)=2.83min2t=tt=3.38+2.83=6.21min>5min再假设降雨历时为7min，通过插得出降雨历时转换系数c=1.15，通过以t距〕为55m，且汇流历时t=6.44min<7min,因此，取降雨历时为7min。展计算，并对汇流历时进展检验，结果列于表7。沟底纵坡BG－A最大排水距离(降雨历时为7min)泄水能力(m泄水能力(m3/s)0.1000.1290.1520.18271846.446.446.446.440.3%0.5%0.7%0%-00.2230.2580.2880.3150.3410.3641.5%2.0%2.5%4.0％6.446.446.446.446.446.44201同样，对BG－B1、BG－B2进展计算得出其在不同纵坡下的最大排水距表8不同沟底纵坡BG－B1〔60*80〕最大排水距离(降雨历时为7min)泄泄水能力(m3/s)0.4860.6280.7430.8881.0871.2561.4041.5381.6611.7762683464094895996927738479159786.916.916.916.916.916.916.916.916.916.910.3%0.5%0.7%0%1.5%2.0%2.5%3.0％3.5％4.0％表9不同沟底纵坡BG－B3(80*80)最大排水距离(降雨历时为9min)泄水能力(m泄水能力(m3/s)0.7340.9481.1221.3411.6421.8962.1202.3222.5082.6814435726778099918.538.538.538.538.538.538.538.538.538.530.3%0.5%0.7%0%1.5%2.0%2.5%3.0％3.5％4.0％-表10不同沟底纵坡BG最大排水距离0.3%~0.5%0.5%~0.7%0.7%~1.0%1.0%~1.5%1.5%~2.0%2.0%~2.5%2.5%~3.0％3.0％~3.5％3.5％~4.0％BG－B1268346409489599692773847915978BG-A7085200BG－B2443572677809991v=n-1R2/3I1/2=0.013-10.1252/30.0031/2=1.053m/s泄水能力为Qc＝Av=0.196×1.053=0.206m3/s5.1沉砂井间距计算大排水距离为55m，此时的设计径流量Q=16.67ΨqF=16.67×0.836×4.445×31.85×l×10-6m3/s＝0.1085-7184201s1.0531.3601.6091.9232.3552.7203.0413.3313.5983.846Qc(m3/s)0.2060.2670.3150.3770.4620.5330.5960.6530.7050.7540.1090.1400.1660.1970.2430.2800.3140.3430.3710.3970.3%0.5%0.7%0%1.5%2.0%2.5%3.0％3.5％4.0％5.2暗埋式边沟最大排水距离的计算历时之和。设降雨历时为5min。-v=n-1R2/3I1/2=0.013-10.1252/30.0031/2=1.053m/s2)汇水面积和径流系数围的汇水面积F＝19.75×l，径流系数取Ψ＝0.95；另外一局部为路堑坡面1的汇水面积F＝(8×1.0+2.6+1.5)×l=12.1×l(8为第一级边坡高度，1.0为第2径流系数取Ψ＝0.65；则，总的汇水面积2F=31.85×l×10-6km2拟定坡面为细粒土坡面，取径流系数Ψ=(0.95×F+0.65×F)/(31.85×l)=0.83623)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路界坡面排水设计重现按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，15年设计重现期时的重现期转换5,10系数为c=1.27，60min降雨强度转换系数为c=0.5，5min降雨历时转换系p605q=1.27×1.25×2.8=4.445mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.836×4.445×31.85×l×10-6m3/s-路线纵坡为3‰时，暗埋式边沟的泄水能力(浅碟式边沟与圆管的泄水能Qc＝Av+Av=0.196×1.053+0.333×0.3=0.306m3/s0.306>16.67×0.836×4.445×31.85×l×10-6为l＝0.306/〔16.67×0.836×4.445×31.85×10-6〕＝155m汇流历时假设石的计算可得，路面汇流历时为2.48min；路堑边坡的地表粗度系数为m=0.4,1坡面横坡为i=1.0，坡高8m，坡面流长度为Ls=(11.3+2.6+1.5)=15.4m(11.3s因此，取t＝3.38min1按式v=n-1R2/3I1/2，得v=n-1R2/3I1/2=0.013-10.1252/30.0031/2=1.053m/s再按式t=l/(60×v)=155/(60×1.053)=2.45min2t=tt=3.38+2.45=5.84min>5min再假设降雨历时为6min，通过插得出降雨历时转换系数c=1.20，通过以t0.3%泄水能力(m3/s)出水口间距(m)汇流历时(min)0.436-展计算，并对汇流历时进展检验，结果列于表13。泄水能力(m泄水能力(m3/s)0.3070.3960.4680.5600.6860.7920.8850.9691.0471.1192092472963624184675125535915.945.945.945.945.945.945.945.945.945.940.3%0.5%0.7%0%1.5%2.0%2.5%3.0％3.5％4.0％6.756.756.756.756.756.756.756.756.756.756.750.5630.6660.7960.9751.1261.2591.3791.4891.5920.5%0.7%%1.5%2.0%2.5%4.0％240310367439537620693760821877-泄泄水能力(m3/s)0.6070.7840.9271.1081.3571.5671.7521.9202.0732.2173504515346387829037.807.807.807.807.807.807.807.807.807.800.3%0.5%0.7%%1.5%2.0%2.5%3.0％3.5％4.0％纵坡暗埋式边沟最大排水距离0.3%~0.5%2403500.5%~0.7%2093104510.7%~1.0%2473675341.0%~1.5%2964396381.5%~2.0%3625377822.0%~2.5%4186209032.5%~3.0％4676933.0％~3.5％5127603.5％~4.0％5538215918771277大排水距离的计算历时之和。设降雨历时为5min。-Am当排水沟纵坡为0.3%时，则v=n-1R2/3I1/2=0.012-10.1412/30.0031/2=1.24m/s2)汇水面积和径流系数设出水口间距为l，两个出水口之间的汇水面积为路面围的汇水面积F＝118.75×l，径流系数取Ψ＝0.95，汇水面积为1F=18.75×l×10-6km23)设计重现期JTJ现5,10系数为c=1.27,60min降雨强度转换系数为c=0.5，5min降雨历时转换系数p60为c=1.25。于是，暴雨强度为5q=1.27×1.25×2.8=4.445mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.95×4.445×18.75×l×10-6m3/sQc＝Av=0.192×1.24=0.238m3/s-0.238>16.67×0.95×4.445×18.75×l×10-6l＝0.238/〔16.67×0.95×4.445×18.75×10-6〕＝180m因路面水汇流历时为2.48min，因此，取t＝2.43min1再按式t=l/(60×v)=180/(60×1.24)=2.42min2t=tt=2.43+2.42=4.85min<5min表16不同路线纵坡纵向集水沟〔0.4*0.6〕最大排水距离(降雨历时为5min)泄水能力(m泄水能力(m3/s)0.2380.3070.3630.4340.5310.6130.6860.7510.8120.8682322753294034655205696156574.854.854.854.854.854.854.854.854.854.850.3%0.5%0.7%0%1.5%2.0%2.5%3.0％3.5％4.0％纵坡纵向集水沟最大排水距离0.3%~0.5%0.5%~0.7%0.7%~1.0%232275-11.0%~1.5%3291.5%~2.0%4032.0%~2.5%4652.5%~3.0％5203.0％~3.5％5693.5％~4.0％615>4.0%657排水管管底纵坡i=2％，可计算得到圆管的(直径＝0.3m)平均流速。g圆形排水管的过水断面面积A＝3.14*/4＝0.071m2，水力半径，R=d/4=0.075v=n-1R2/3I1/2=0.01-10.0752/30.021/2=2.515m/sQc＝Av=0.071×2.515=0.179m3/s根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.95×4.445×18.75×l×10-6m3/s179m3/s0.179>16.67×0.95×4.445×18.75×l×10-6l＝0.179/〔16.67×0.95×4.445×18.75×10-6〕＝135m-泄水能力(m3/s)最大排水距离l(m)0%0.126952.0%0.1793.0％0.2194.0％0.253L——挖方路段长度〔纵向集水沟的排水长度〕l——按单根横向排水管泄水能力控制的纵向集水沟最大排水距离n——横向排水管设置数量表17-2填挖交界位置〔较低一侧〕横向排水管设置数量满满足纵向集水沟的最大排水长度L(m)95257338256377498318470622横向排水管底坡度(%)1.0％2.0%3.0％4.0％横向排水管设置数量n1234123412341泄水能力(m3/s)0.1260.2520.3780.5040.1790.3580.5370.7160.2190.4380.6570.8760.253-2340.5060.7591.0123685457221〕对于路堑边沟排水长度L≤250m的路段，采用浅碟式边沟或暗埋式边①对于路堑边沟排水长度L≤50m的路段，采用边沟(一)；mLm，前50m路段采用边沟③对于路堑边沟排水长度150m＜L≤250m的路段，前50m路段采用边表18拟采用BG最大排水距离沟底纵坡(沟底纵坡(%)BG-1浅碟式BG-2暗埋式50BG-3暗埋式600.3%~0.5%0.5%~0.7%20924031070表19BG型式选择一览表边边沟形式排水距离L≤50m50＜L≤150m150＜L≤250m50mBG-2BG-2BG-3面边沟的排水长度。例如，对于长度为150m的路堑路段，前面50m采用BG-1，后面100m采用BG-2〔BG-2的2、各类边沟之间通过沉砂井进展衔接。2〕对于路堑边沟排水长度L＞250m的路段，均采用矩形边沟，具体型式-截水沟和截水沟等排水设施来排除和拦截路界围外的雨水。现按照"公路排水设计规"JTJ018-97的规定，通过计算设计径流量反算各种排水设施各型号的最大排水距离(即出水口距离)和面积，为确定各路段各种排水设施型号的选取提供参历时之和。设降雨历时为3min。拦水路缘石与路肩铺面构成的浅三角型过水断面的泄水能力为：Qc＝0.377×h8/3×I1/2/〔i×n〕＝0.377×0.058/3×I0.5/〔0.02×0.013〕h2)汇水面积和径流系数F=l×16.0×10-6km2取径流系数Ψ=0.95。3)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路面和路肩外表排水5年。-按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，5年设计重现期时的重现期5,10转换系数为c=1.0,60min降雨强度转换系数为c=0.5，3min降雨历时转换p605q=1.0×1.40×2.8=3.92mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.95×3.92×l×16.0×10-6m3/s6〕拦水缘石最大排水距离的计算Qc＝0.377×h8/3×I1/2/〔i×n〕＝0.377×0.058/3×0.0050.5/h0.035>16.67×0.95×3.92×l×16.0×10-6为l＝0.035/〔16.67×0.95×3.92×16.0×10-6〕＝35m历时假设由表查得地表粗度系数为m=0.013,路面横坡为i=0.02,坡面流长度为1sLs=16.0m，可计算得到坡面汇流历时-按式v=20i0.6得v＝20×0.0050.6=0.83m/s，g再按式t=l/(60×v)=35/(60×0.83)=0.70min2it=tt=1.73+0.70=2.43min<3min展计算，并对汇流历时进展检验，结果列于表1。离泄水能力(m泄水能力(m3/s)0.0350.0410.0490.0600.0700.0780.0850.0920.0982.432.412.382.362.342.332.322.312.30356170788693990.5%0.7%0%1.5%2.0%2.5%3.0%3.5%4.0%知，拦水路缘石的最大排水距离随着路线纵坡的加大而增大，汇流历时均小于3min。因此，现拟定:当路线纵坡为0.5%~0.7%时，出水口间距设为35m；当路线纵坡为0.7%~1.0%时，出水口间距设为40m；当路线纵坡为1.0%~1.5%时，出水口间距设为50m；当路线纵坡为1.5%~2.0%时，出水口间距设为60m；当路线纵坡为大于2.0%时，出水口间距设为70m。-的排水沟。由急流槽槽底纵坡〔即路堤边坡坡度i=1:1.5〕i=66.7％，可计算ggmm流槽的过水能力v=n-1R2/3I1/2=0.015-10.0892/30.6671/2=10.85m/s设路基填土为7米高，则急流槽长度l为10.5m，可得到急流槽的沟管汇t=l/(60×v)=10.5/(60×10.85)=0.016min3影响可忽略不计。因此，降雨历时仍为3min时，暴雨强度为3.92mm/min。因此，根据"公路排水设计规"JTJ018-97，设计径流量仍为Q=16.67ΨqF=16.67×0.85×3.92×l×16.0×10-6m3/s当急流槽沟底纵坡为66.7％时，矩形急流槽的泄水能力为Qc＝Av=0.064×10.85=0.694m3/s2。水口间距的设计径流量300.031-00.0360.0440.0530.0623560由表2可知，急流槽泄水能力远大于按各种间距设置出水口时的设计径流面汇流历时与沟的沟管汇流历时之和。设降雨历时为10min。断面面积A为0.288m2，过水断面湿周ρ为1.56m，水力半径R＝A/ρ=0.185m，当排水沟纵坡0为.3%时，则v=n-1R2/3I1/2=0.015-10.1852/30.0031/2=1.18m/s2)汇水面积和径流系数局部组成：一局部为路面围的汇水面积F＝16.0×l，径流系数取Ψ＝0.95；1另外一局部为路堤坡面的汇水面积F＝(7×1.5+1)×l=11.5×l(7为边坡高度，22积F=27.5×l×10-6km2取径流系数Ψ=(0.95×F+0.65×F)/(27.5×l)=0.82523)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路界坡面排水设计重-按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，15年设计重现期时的重现5,10期转换系数为c=1.27,60min降雨强度转换系数为c=0.5，10min降雨历时p605q=1.27×1.0×2.8=3.556mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.825×3.556×27.5×l×10-6m3/sQc＝Av=0.288×1.18=0.341m3/s0.341>16.67×0.825×3.556×l×27.5×10-6为l＝0.341/〔16.67×0.825×3.556×27.5×10-6〕＝254m设拦水缘石的计算可得，路面汇流历时为2.43min；路堤边坡的地表粗度系数为m=0.4，坡面横坡为i=0.667，坡面流长度为Ls=13.62m〔填土高度7m，1s-因此，取t＝3.51min1按式v=n-1R2/3I1/2=0.015-10.1852/30.0031/2=1.18m/s再按式t=l/(60×v)=254/(60×1.18)=3.57min2t=tt=3.51+3.57=7.08min<10min再假设降雨历时为7min，通过插得出降雨历时转换系数c=1.15，暴雨强t度为q=1.27×1.15×2.8=4.089mm/min，通过以上过程的计算得到，当沟lm汇流历时t=6.61min<7min，因此，取降雨历时为7min。当路线纵坡为其它数值时，按照上述计算过程对PSG－1型最大排水距离进展计算，并对汇流历时进展检验，结果列于表3。泄水能力(m泄水能力(m3/s)0.3410.4400.5210.6230.7620.8800.9841.0781.1651.2452202853374024935696366977538056.616.616.616.616.616.616.616.616.616.610.3%0.5%0.7%.0%1.5%2.0%2.5%3.0％3.5％4.0％-表4不同沟底纵坡PSG－2(80*60)最大排水距离(降雨历时为8min)泄泄水能力(m3/s)0.5080.6560.7760.9281.1361.3121.4671.6071.7361.8563444435256277688879927.847.847.847.847.847.847.847.847.847.840.3%0.5%0.7%1.0%1.5%2.0%2.5%3.0％3.5％4.0％表5不同沟底纵坡PSG－3(80*80)最大排水距离(降雨历时为10min)泄水能泄水能力(m3/s)0.7340.9481.1221.3411.6421.8962.1202.3222.5082.6819.869.869.869.869.869.869.869.869.869.865467058349970.3%0.5%0.7%1.0%1.5%2.0%2.5%3.0％3.5％4.0％同沟底纵坡PSG最大排水距离0.3%~0.5%220PSG-2344PSG-3546-00.5%~0.7%2854437050.7%~1.0%3375258341.0%~1.5%4026279971.5%~2.0%49376812212.0%~2.5%56988714102.5%~3.0％63699215763.0％~3.5％69717273.5％~4.0％7531865805125419944．边沟最大排水距离的计算 BG－A型 历时之和。设降雨历时为5min。v=n-1R2/3I1/2=0.05-10.1432/30.0031/2=0.30m/s2)汇水面积和径流系数围的汇水面积F＝16.0×l，径流系数取Ψ＝0.95；另外一局部为路堑坡面的1汇水面积F＝(8×1.0+2.6+1.5)×l=12.1×l(8为第一级边坡高度，1.0为第一22F=28.1×l×10-6km2拟定坡面为细粒土坡面，取径流系数-Ψ=(0.95×F+0.65×F)/(28.1×l)=0.82123)设计重现期TJ5,10系数为c=1.27，60min降雨强度转换系数为c=0.5，5min降雨历时转换系p605q=1.27×1.25×2.8=4.445mm/min5〕BG－A型边沟最大排水距离计算根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.821×4.445×28.1×l×10-6m3/sQc＝Av=0.333×0.3=0.1m3/s0.1>16.67×0.821×4.445×28.1×l×10-6l＝0.1/〔16.67×0.821×4.445×28.1×10-6〕＝58m历时假设-m1坡面横坡为i=1.0，坡高8m，坡面流长度为Ls=(11.3+2.6+1.5)=15.4m(11.3s因此，取t＝3.38min1按式v=n-1R2/3I1/2，得v＝0.05-10.1432/30.0031/2=0.3m/s再按式t=l/(60×v)=58/(60×0.3)=3.22min2t=tt=3.38+3.22=6.60min>5min再假设降雨历时为7min，通过插得出降雨历时转换系数c=1.15，通过以t距〕为63m，且汇流历时t=6.91min<7min,因此，取降雨历时为7min。展计算，并对汇流历时进展检验，结果列于表7。沟底纵坡BG－A最大排水距离(降雨历时为7min)泄水能力(m泄水能力(m3/s)0.1000.1290.1520.1820.2230.2580.2880.3156382972016.916.916.916.916.916.916.916.910.3%0.5%0.7%0%1.5%2.0%2.5%3.0％-0.3410.3646.916.91217232同样，对BG－B1、BG－B2进展计算得出其在不同纵坡下的最大排水距离，结果列于表8、9。表8不同沟底纵坡BG－B1〔60*80〕最大排水距离(降雨历时为8min)7.637.637.637.637.637.637.637.637.637.63泄水能力(m3/s)0.4860.6280.7430.8881.0871.2561.4041.5381.6611.7763234174945907238359330.3%0.5%0.7%%1.5%2.0%2.5%3.0％3.5％4.0％表9不同沟底纵坡BG－B3(80*80)最大排水距离(降雨历时为10min)水能力(m3/s)0.7340.9481.1221.3411.6421.8962.1202.3222.5082.6815376938209809.629.629.629.629.629.629.629.629.629.620.3%0.5%0.7%%1.5%2.0%2.5%3.0％3.5％4.0％表10不同沟底纵坡BG最大排水距离-BG-ABG－B1BG－B20.3%~0.5%603235370.5%~0.7%804176930.7%~1.0%954948201.0%~1.5%5909801.5%~2.0%7232.0%~2.5%8352.5%~3.0％9333.0％~3.5％2003.5％~4.0％215230v=n-1R2/3I1/2=0.013-10.1252/30.0031/2=1.053m/s泄水能力为Qc＝Av=0.196×1.053=0.206m3/s5.1沉砂井间距计算大排水距离为63m，此时的设计径流量Q=16.67ΨqF=16.67×0.821×4.445×28.1×l×10-6＝0.108m3/s，由此可-638297201217232s1.051.361.611.922.362.723.043.333.603.85Qc(m3/s)0.2070.2670.3160.3780.4620.5340.5970.6540.7060.7550.1080.1400.1660.1980.2430.2800.3130.3440.3710.3970.3%0.5%0.7%0%1.5%2.0%2.5%3.0％3.5％4.0％5.2暗埋式边沟最大排水距离的计算历时之和。设降雨历时为5min。v=n-1R2/3I1/2=0.013-10.1252/30.0031/2=1.053m/s2)汇水面积和径流系数围的汇水面积F＝16.0×l，径流系数取Ψ＝0.95；另外一局部为路堑坡面的1-汇水面积F＝(8×1.0+2.6+1.5)×l=12.1×l(8为第一级边坡高度，1.0为第一22F=28.1×l×10-6km2拟定坡面为细粒土坡面，取径流系数Ψ=(0.95×F+0.65×F)/(28.1×l)=0.82123)设计重现期根据"公路排水设计规"JTJ018-97的规定，高速公路路界坡面排水设计重现按公路所在地区，查"公路排水设计规"JTJ018-97得5年设计重现期10min降雨历时的降雨强度为q＝2.8mm/min，15年设计重现期时的重现期转换5,10系数为c=1.27，60min降雨强度转换系数为c=0.5，5min降雨历时转换系p605q=1.27×1.25×2.8=4.445mm/min根据"公路排水设计规"JTJ018-97，设计径流量为Q=16.67ΨqF=16.67×0.821×4.445×28.1×l×10-6m3/sQc＝Av=0.196×1.053+0.333×0.3=0.306m3/s0.306>16.67×0.821×4.445×28.1×l×10-6-为l＝0.306/〔16.67×0.821×4.445×28.1×l×10-6〕＝179m检验汇流历时假设1坡面横坡为i=1.0，坡高8m，坡面流长度为Ls=(11.3+2.6+1.5)=15.4m(11.3s因此，取t＝3.38min1按式v=n-1R2/3I1/2，得v=n-1R2/3I1/2=0.013-10.1252/30.0031/2=1.053m/s再按式t=l/(60×v)=179/(60×1.053)=2.83min2t=tt=3.38+1.915=6.21min>5min再假设降雨历时为7min，通过插得出降雨历时转换系数c=1.15，通过以t展计算，并对汇流历时进展检验，结果列于表13。0.3%0.3%泄水能力(m3/s)出水口间距(m)汇流历时(min)0.4360.3%泄水能力(m3/s)出水口间距(m)汇流历时(min)0.607-水能力(m3/s)0.3070.3960.4680.5600.6860.7920.8850.9691.0471.1192522983564365035636166667126.466.466.466.466.466.466.466.466.466.460.3%0.5%0.7%%1.5%2.0%2.5%3.0％3.5％4.0％7.447.447.447.447.447.447.447.447.447.447.440.5630.6660.7960.9751.1261.2591.3791.4891.5922903744435296487488379179900.5%0.7%%1.5%2.0%2.5%4.0％8.78.738.738.738.738.738.738.738.730.7840.9271.1081.3571.5671.7521.9204235466467729450.5%0.7%%1.5%2.0%2.5%3.0％1-22.0732.2178.738.73纵坡暗埋式边沟最大排水距离0.3%~0.5%2904230.5%~0.7%2523745460.7%~1.0%2984436461.0%~1.5%3565297721.5%~2.0%4366489452.0%~2.5%50374810922.5%~3.0％56383712203.0％~3.5％61691713373.5％~4.0％66699014447121544大排水距离的计算历时之和。设降雨历时为5min。Am当排水沟纵坡为0.3%时，则v=n-1R2/3I1/2=0.012-10.1412/30.0031/2=1.24m/s2)汇水面积和径流系数设出水口间距为l，两个出水口之间的汇水面积为路面围的汇水面积F＝-15×l，径流系数取Ψ＝0.95，汇水面积为