地基沉降量计算

1、创作：欧阳理时间：2021.03.05地衷变形恵其素禹形咸的垂宜变形蜃烈签建疑物的溝恵外再裁作用下地衷土雇彼在拓达到稳応时晁舷蔻面 的沉悻蜃稀签地基星件范韩龙。一、今雇总和该针篇地哀儼给沉阶蜃针算地晁的儼终沉悻蜃，目谕眾纟用的就是今层总和 工O(-)衷淙原理钱方该E考盅地裹的垂向变形，没韦考盅侧向变形， 地衷的变形同字內侧限层拓试验屮的楷况表冷一致，属 一赧卷拓同廳。地屍的儼終沉粋蜃可用室內在拓试瞼确 氏的泰毅他、£, a)进行针篇，痛炙换后得：式彳：S地衷舉终況障蜃（mm丿； -地裹爱為悄（自喳应力作用下丿的孔隙比；W2 地基爰為（自重昌附加应力作用下丿沉悻穗定 后的孔隙比，H土层

2、的唐应。针算沉悻蜃时，在地屍可憐爰為变形的层拓眉范国 內，根倨土的特槌、盜力状态M及地下水儘連行今层。 銘后按式（49丿或64-10；针算各今层的況悻蜃Si。 后将各今眉的沉炸蜃总和趁来即签地臭的儼终沉悻蜃；（二）针算步骡1；刻今土层4-7所示，各夭磁土层探面和地下水儘独须作岛 令层尿輸;各今雇唐灰扯须满足H0O.4B （B %农蔻 宽幻。2）计篇表蔻附加空力po3丿计篇各今层界面的自重盜力 氐和附餉盜力6;弄 伦制溢力今怖曲钱。4；确灾圧矯雇考及满足6=0.26乙的深度点可作尙狂、儒层的下限，对孑怨土则应满足(7-=0A(7Sz；对一锻建筑扬可按下式针算”=B(2.50.41nB)。5；计篇

3、各今层餉裁囁后的年射垂直盜力pi=6z； P2=6z+66)按各今层的卩1和"2在曲钱止圭取相溢的孔隙比 或确虧4 E著其它爲拓徃犒标7丿根倨耒同的层拓柑指标，迄用公式(4-9)、(410；针篇各今层的沉悻蜃Si8丿按公式(411丿针算总況障蜃S。今层总和试的县俸计篇过程可彖糾魏41。何軀41己知禅下单独方形1M,衷砒彖而尺寸签2.5x2.5m,悝深2m,作用孑表舷上(殺针地血标爲处J 的轴向再裁N=1250kN,帝关地裹勒塞资抖号衷砒剧禹 祥见下囹。试用草向今眉总和该针算瘟础屮点舉終沉粋 f o解：按单向今雇总和注针壽(1丿针算地屍土的自重盜力。Z自疫彖标咅趁篇。£ z=

4、0m, 6d=19.5x2=39 (kPa丿z=lm, 6t=39+19.5x1=58.5 (kPa丿z=2m, 6zi=58.5+20x1=78.5 (kPa丿z=3m, <t.s-i=78.5+20x 1=98.5 (kPa丿z=4m, 1=98.5+(20-10)x1=108.5 (kPa丿z=5m,(7.szi=108.5+(20-10)xl = l 18.5 (kPa丿z=6m,心1=118.5+18.5><1 = 137 (kPa丿z=7m, (7.Sri=l37+18.5x1 = 155.5 (kPa丿(2) 屍蔻压力计篇。衷砒蔻面M上，衷砒马镇土 的覘合客重瑕

5、Yo=20kN/m30(3) 裹蔻附餉圧力针算。(4) 裹砒屮点下地屍屮聲向附加溢力计篇。用角支该针壽，L/B=, a:,i=4Ksi'po.圭附加盜 力系叙素得Ksio(5) 确灾沉悻计篇深应乙考虑第点土层拓槌比第雇土女，殘针算后 确定.Z"=7m,见下乗。例题41计算表格1Z(m)ZB/2Ks(kPa)% (kPa)Oz/Osz(%)(m)000.250 02013910.8099 9160.75&521.60.112390.297&532.40.064 251.629&843.20.040 132.24108.529.7154.00.027 02

6、1.71118.518.3264.80.019 315.5213711.3375.60.014 811.9()155.57.6按7m计(6丿针篇疫舷屮点眾终沉悻蜃。利用勒塞资料屮 的e-p曲钱，朮按单向今层总和注公式例靈41针算素梏2Z(m )仏 (kPa)%(kPa)H(cm)自重应力 平均值(kPa)附加应力 平均值(kPa)& +己(kPa)666(kPa1)焉=a(kPa)(cm)$ =(cm)03920110010010010010010010048. 7568. 5088. 50103.5113. 5127.5146. 25180. 85125. 5070. 9641.93

7、26. 9818 6213.71229.6194159.46145. 43110. 48116. 12159. 960. 710. 640. 6350. 630. 630. 690.680. 640.610. 620. 620. 620. 680. 670.0003870.0002390.0002110.0002380.0003710.0005370.00072911186861774968484393314723041.091.830. 920.610.610. 590. 595. 926. 847. 458. 068. 659. 24158.5160.7278.590.29398.551.

8、624108.532.245118.521.71613715.527155.511.90二、建媒地裹衷舷孩针规范稚爲的沉陳针算该下而计算沉悻蜃的方该足建媒地屍表舷说针规范 (GBJ7-89丿所推爲的，简烈规范稚爲注，痛时也 叫拓力面彩注。(_)针算原理盜力面积注一毅按地屍土的夭磁今眉面刻今针算土 层，引入土层年射附加应力的概念，通过年妁附加应力 系毅，舒晁蔻屮皿"下地屍屮乙-乙深度范(8的附加应力 按劣卤张原则化签相同深及范国內崔形今怖时的今怖盜 力女小，再按軀形今怖疝力槁况针算土层的在、编啖,各 土层卷拓蜃的总和即务地裹的计算沉悻蜃。理论上屍砒 的年杓沉悻蜃可热示签式屮：S地裹儼終

9、況悻蜃(mm丿；/地裹层拓层(即爱层层丿范国內所刻今的土层 叙:po-晁砒蔻处的附加爲力(kPa丿；必晁础蔻下第，层土的爲拓栈蜃(MPa)；Zi、Zi-I今剔尙泉磁蔻而至第,雇和第!“层蔻面的 雅南(m) /5、弘L今别务屍砒蔻面针壽支至第j层和第M 4蔻面范国內年杓附加凌力系叙，可妾素41。衣4J矩形面积上均布荷载作用下，通过中心点竖线上的平均附加应力系数&z/BL/B1.01.21.41.61.82.02.42.83.23.64.05.0>100. 01.0001.0001.0001.0001.0001.0001.0001.0001.0001.0001.0001.0001.0

10、000.9970.9980.9980.9980.9980.9980.9980.9980.9980.9980.9980.9980.998U10.9870.9900.9910.9920.9920.9920.9930.9930.9930.9930.9930.9930.9930.20.9670.9730.9760.9780.9790.9790.9800.9800.9810.9810.9810.9810.9820.30.9360.9470.9530.9560.9580.9650.9610.9620.9620.9630.9630.9630.9630.40.9000.9150.9240.9290.9330.

11、9350.9370.9390.9390.9400.9400.9400.9400.8580.8780.8900.8980.9030.9060.9100.9120.9130.9140.9140.9150.9150 50.8160.8400.8550.8650.8710.8760.8810.8840.8850.8860.8870.8870.888z /*0.7750.8010.8190.8310.8390.8440.8510.8550.8570.8580.8590.8600.8600. 6A 70.7350.7640.7840.7970.8060.8130.8210.8260.8290.8300.8

12、310.8320.833U/0 Q0.6980.7230.7490.7640.7750.7830.7920.7980.8010.8030.8040.8060.807Uo0.6630.6940.7170.7330.7440.7530.7640.7710.7750.7770.7790.7800.7820. 90.6310.6630.6860.7030.7150.7250.7370.7440.7490.7520.7540.7560.7580.6010.6330.6570.6740.6880.6980.7110.7190.7250.7280.7300.7330.7351.00.5730.6050.62

13、90.6480.6610.6720.6870.6960.7010.7050.7080.7110.7141.10.5480.5800.6040.6220.6370.6430.6640.6760.6790.6830.6860.6900.6931.20.5240.5560.5800.5990.6130.6250.6410.6510.6580.6630.6660.6700.6751 Q0.5020.5330.5580.5770.5910.6030.6200.6310.6380.6430.6460.6510.656丄 o0.4820.5130.5270.5560.5710.5830.6000.6110.

14、6190.6240.6290.6330.6381.40.4630.4930.5170.5360.5510.5630.5810.5930.6010.6060.6100.6160.622n 二0.4460.4750.4990.5180.5330.5450.5630.5750.5840.5900.5940.6000.6061 00.4290.4590.4820.5000.5150.5280.5460.5590.5670.5740.5780.5850.5911.60.4140.4430.4660.4840.4990.5110.5300.5430.5520.5580.5630.5700.5771. 70

15、.4000.4280.4510.4690.4840.4960.5150.5280.5370.5440.5480.5560.5641.803870.4140.4360.4540.4690.4810.5000.5130.5230.5300.5350.5430.5511.903740.4010.4230.4410.4550.4680.4860.5000.5090.5160.5220.5300.5390.3620.3890.4100.4280.4420.4550.4730.4870.4960.5040.5090.5180.528C z0.35103770.3980.4160.4300.4420.461

16、0.4740.4840.4920.4970.5060.5172. 00.3410.36603870.4040.4180.4300.4490.4630.4720.4800.4860.4950.5062. 10.33103560.3770.3930.4070.4190.4380.4510.4610.4690.4750.4850.4962.20.3220.34603660.38303970.4090.4270.4410.4510.4590.4650.4740.4872. 30.3130.3370.3570.3730.38703980.4170.4300.4400.4480.4540.4640.477

17、2.4030503280.3480.364037703890.4070.4200.4310.4390.4450.4550.4680.2970.3200.33903550.36803790.3970.4110.4210.4290.4360.4460.4602 50.2890.3120.3310.3460.3590.3710.3880.4020.4120.4200.4270.4370.4522.60.28203040.323033803510.3620.3800.3930.4030.4120.4180.4290.444o 70.2760.2970.31503300.3430354037203850

18、.3950.4030.4100.4210.436乙./0.2690.2900.3080.3230.33503460.36403770.3870.3950.4020.4130.4292.80.2630.2840.3010.31603280.33903560.36903790.3880.3940.4050.4222.90.2570.2770.2940.3090.32103320.3490.36203720.3800.3870.3980.4150.2510.2710.2880.302031403250342035503650.37303790.3910.4083.00.2460.2650.2820.

19、2960.308031803350.3480.3680.3660.3720.3840.4023. 10.2410.2600.2760.2900.30203120.32803410.3520.3590.3660.3770.396r c0.2360.2550.2700.2840.2960.306032203350.3450.3630.3590.3710.3903. 23.30.2310.2500.2650.2780.2900.3000316032903390.3470.3530.3650.3843.43.53.63.73.83.94.04. 14.24.34.44.54.64.74.84.95.0

20、0.2260.2450.2600.2730.2850.29403100.2220.2400.2550.2680.2790.2890.3050.2180.2350.2500.2630.2740.2840.2990.2140.2310.2450.2580.2690.2790.2940.2100.2270.2410.2530.2650.2740.2890.2060.2230.2370.2490.2600.2690.2840.3230.3170.3120.3060.3010.2960.3330.3410.3470.35903270.3350.3410.3530.3210.32903360.3470.3

21、160.32403300.3420.3110.3190.3250.3370.3060.3130.3200.3320.3780.3730.3670.3620.3570.352(二丿规范推老公式由(4-12)式乘M沉悻计篇務验系赦即岛规 范推爲的沉悻计篇公式：式屮：必一沉強针尊務脸系毅，盜根倨同类地g己韦房屋 和构疑物实侧儼络沉悻蜃马针尊沉粋蜃对比确 L 一钗采用4-2的超值，表4-2沉降计算经验系数炉基底附加 压力 /?o(kPa)圧缩模量E(MPa)2.54.07.015.020.01.41.31.00.40.2po<O.15fk1.11.00.70.40.2注：家列毅值可內插；由变形针

22、算深度范®內韦多层土讨，ES可按附加 疝力而叙A的加权年妁值痕用，即（三）地屍爰巫层针算深凌的确灾针算深应乙可按下述方依确宠1；矗在相邻肴截彩响的宿况下，溢满足下式宴朮：式屮：$/虚深应乙处，向上取计篇唐应岛Zz的针算 变形值/ z圭热4-3 ；表4-3 Zz取值B(m)<22<B<44<B<88<B<1515<B<30>30z(m)0.30.60.81.01.21.5 s/在深虔乙范国內，第 n的计尊变形蜃。2）对尢相邻為我的独立表舷，可按下列简祀的證瞼 公式确圧沉悻针算深及乙“规范法的具俸计算过程可彖例魏42。【例魏4

23、2】己知棹下单独方形衷%虬 痕赵彖尺寸伶2.5x2.5m,惟深2m,作用于疫舷上（殺计地血标名处J 的轴向希裁N=1250kN,韦关地衷勒家资料号衷砒剧百 祥见下囹。试用规范依针算晁舷屮支儼終沉悻蜃。解；按建红地衷屍舷茯针规范针篇，采用下式，针 算箱赛祥见下素。例题4-2计算表格2(m)L/Bz/B葩(kPa)f ° (瓦召"込_】勺_)(cm)(cm)000. 250001.00.80. 23460. 23460. 231644184. 274272.01.60. 19390. 38780. 153268611.806. 073.02 52.40. 15780. 4734

24、0. 085677490. 896. 964.03.20. 13100. 52400. 050668180. 597. 555.04.00. 11140. 55700.03313930. 608. 156.04.80. 09670. 58020. 023231470. 598. 747.05.60. 08520. 59640. 0162230!0. 579.317.66. 080. 08040. 61100. 0146350000.039. 34按规范确空爰爲点下限，Z=2.5(2.5-0.41n2.5)=5.3m；由孑下面土层啊荻務，在层桔土 蔻面以下取G唐及针篇，根据乗43的要朮，取 z=

25、0.6m,则z“=7.6m,针篇得唐应 山 的沉悻蜃岛 0.03cm,满足宴求。t 4-2得況悻针篇殘验系叙孙=1.17。那么，三、按桔柑土的沉悻机理针算沉悻根倨対桔仪土地裹在局部（裹舷丿看裁作用下的实隊 变形特征的观察和今祈，桔柑土地裹的沉悻S可M认岛 是由机理耒同的三梆今沉悻值啟（ 4-8；,亦即；式彳：s一瞬时沉悻（亦蘇刼胎沉強丿；Sr国穡沉悻（亦秸殳国猪沉悻丿；S$浪囿箱沉悻（亦稀蠕变沉悻丿O篦时沉律足指加裁后地屍瞬时农或的況悻。由孑痕舷 加裁卤彩签韦限尺寸，餉裁后地衷彳会备龙盜变产或， 龙溢变会引趁側向变形而造咸瞬时沉悻。国偌滅障是指饱和与摟近饱和的桔徃土恵表砒捋裁作 用下，<

26、4<#孔隙水层力的消傲，土骨架产吻变形所 造啟的沉悻（囿箱层鑽丿O囿穡沉粋建車取决于孔隙水 的排出速卑。决国修沉禅足指空圃箱过程孔隙水层力消徽过 程丿秸束后，在韦数溢力耒变的楷况下，土的骨需啊随 时间経礦农望变形。这种变形的速卑取决于土骨需冷身 的嫦变槌质。（_）瞬时沉悻针篇瞬时沉悻没韦俸報变形，可认尙臭稗性变形，此一 殿按禅槌理他针尊，按式64-17；朮斛。式屮；沉悻系超，可以素44屮圭用,P0裹彖附加应力;冷张桜比，这时是恵耒排水条件下没痛俸叙变形所 产望的变形蜃，所M盜取“=0.5/E耒桃水变形模蜃，纟根倨耒排水抗穹强灰C“和 E,的務脸关系式（418丿朮得。上式屮的佩值适用于談怨的、爲塑般韦机土，爲值适 用于一殿轶硬的桔柑土。表4-4沉降系数3值受荷面