1、单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,TB 10018-2018,铁路工程地质原位测试规程,(动力触探试验),宣贯培训,2018,年,1,前 言,本规程是根据,国家铁路局关于印发,的通知,(国铁科法函,【2015】62,号)的要求,在,铁路工程地质原位测试规程,(,TB 10018-2003,)的基础上修订而成。,本规程内容包括总则、术语和符号、平板载荷试验、螺旋板载荷试验、十字板剪切试验、旁压试验、标准贯入试验、动力触探试验、静力触探试验、应力铲试验、扁板侧胀试验、旋转触探试验等,12,章,另有,3,个附录。,2,前 言,本规程修订的主要内容
2、如下:,1.,增加了深层平板载荷试验、自钻式旁压试验、有效应力铲试验、旋转触探试验等原位测试技术方法。,2.,增加了旁压试验确定水平基床系数、有效应力铲试验确定静止侧压力系数、扁板侧胀试验确定水平固结系数等方面的内容。,3.,修订了孔压消散试验确定水平固结系数、扁板侧胀试验确定水平基床系数等方面的内容。,4.,删除了岩体直剪试验,机械式十字板试验等内容。,3,一,、,一般规定,1.,动力触探适用于黏性土、砂类土、碎石类土、全风化岩、强风化岩。,2.,动力触探可分为轻型、重型和特重型。轻型动力触探可确定一般黏性土地基承载力,重型和特重型动力触探可确定中砂以上的砂类土、碎石类土的地基承载力,测定圆
3、砾土卵石土的变形模量。动力触探还可用于查明地层在垂直和水平方向的均匀程度和确定桩基持力层。,3.,动力触探划分土层并定名时,应与其他勘探测试手段相结合;确定地基承载力或变形模量时,动力触探孔数应根据场地大小、建筑物等级及土层均匀程度综合考虑,但同一场地应不少于,3,孔。,4,二、,试验设备,动力触探使用的设备类型和规格如表,1,类型,重锤质量(,kg,),重锤落距(,cm,),探头截面积(,cm,2,),探杆外径(,mm,),动力触探击数,符号,单位,轻型,100.2,502,13,25,N,10,击,/30cm,重型,63.50.5,762,43,42,、,50,N,63.5,击,/10cm
4、,特重型,1201.0,1002,43,50,N,120,击,/10cm,5,图,1,轻型动力触探仪探头外形尺寸(单位:,mm,),6,图,2,重型、特重型动力触探仪探头外形尺寸(单位:,mm,),7,三、试验要点,1.,动力触探作业前必须对机具设备进行检查,确认正常后方可启动。部件磨损及变形超过下列规定者,应予更换或修复。,(,1,)探头允许磨损量,:,直径磨损不得大于,2mm,锥尖高度磨损,不得大于,5mm,。,(,2,)每节探杆非直线偏差不得大于,0.6%,。,(,3,)所有部件连接处丝扣应完好,连接紧固,2.,动力触探机具安装必须稳固,在作业过程中支架不得偏移。,3.,动力触探时,应始
5、终保持重锤沿导杆铅直下落,锤击频率应控制在,15,击,/min30,击,/min,。,4.,轻型动力触探作业时,应先用轻便钻具钻至所需测试土层的顶面,然后对该土层连续贯入。当贯入,30cm,的击数超过,90,击或贯入,15cm,超过,45,击时,可停止作业。如需对下卧层进行测试,可用钻探方法穿透该层后继续触探。,8,三、试验要点,5.,根据地层强度的变化,重型和特重型动力触探可互换使。重型动力触探实测击数大于,50,击,/10cm,时,宜改用特重型当重型动力触探实测击数小于,5,击,/10cm,时,不得采用特重型动力触探。,6.,在预钻孔内进行重型或特重型动力触探作业,钻孔孔径大于,90mm,
6、、孔深大于,3m,、实测击数大于,8,击,/10cm,时,可用小于或等于,90mm,的孔壁管下放至孔底或用松土回填钻孔,以减小探杆径向晃动。,7.,各种类型动力触探的锤座距孔口高度不宜超过,1.5m,,探杆应保持竖直。,8.,轻型动力触探应每贯入,30cm,记录其相应击数。,9.,重型、特重型动力触探应每贯入,10cm,记录其相应击数。地层松软时,可采用测量每阵击,(,一般为,1,击,5,击,),的贯入度,并按下式换算成相当于同类型动力触探贯入,10cm,时的击数:,9,三、试验要点,N63.5;N120=10n/s,式中,:N63.5-,重型动力触探实测击数,(,击,/10cm);,N120
7、-,特重型动力触探实测击数,(,击,/10cm);,n-,每阵击的击数,(,击,),s-,每阵击时相应的贯入度,(cm),10.,现场记录应清晰完整,除按本规程表,B.4.1,表,B.4.3,中项目填写外,并应在备注栏中记录下列事项,:,1,贯入间断原因及时间。,2,落距超限量、落锤回弹情况。,3,探杆及导杆偏斜及径向震动情况。,4,接头紧固情况。,5,其他异常情况。,10,四、,资料整理与计算,1.,动力触探记录应在现场进行初步整理,并对记录的击数和贯入尺寸进行校核和换算。,2.,轻型动力触探应以每层实测击数的算术平均值作为该层的触探击数平均值,N10,。,3.,重型动力触探实测击数,N,6
8、3.5,应按下式进行杆长击数修正,:,N,63.5,=a,1,N,63.5,式中,:N,63.5,-,重型动力触探修正后击数,(,击,/10cm);,a,1,-,重型动力触探杆长击数修正系数,可按下表确定。,11,四、,资料整理与计算,N63.5,杆长,L,5,10,15,20,25,30,35,40,50,2,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,-,4,0.96,0.95,0.93,0.92,0.90,0.89,0.87,0.86,0.84,6,0.93,0.90,0.88,0.85,0.83,0.81,0.79,0.78,0.75,8,0.90,0.86,0.8
9、3,0.80,0.77,0.75,0.73,0.71,0.67,10,0.88,0.83,0.79,0.75,0.72,0.69,0.67,0.64,0.61,12,0.85,0.79,0.75,0.70,0.67,0.64,0.61,0.59,0.55,14,0.82,0.76,0.71,0.66,0.62,0.58,0.56,0.53,0.50,16,0.79,0.73,0.67,0.62,0.57,0.54,0.51,0.48,0.45,18,0.77,0.70,0.63,0.57,0.53,0.49,0.46,0.43,0.40,20,0.75,0.67,0.59,0.53,0.48,
10、0.44,0.41,0.39,0.36,12,四、,资料整理与计算,当采用特重型动力触探确定碎石类土密实度时,实测击数,N,120,应按下式进行杆长击数修正:,N120=,2,N,120,式中:,N,120,特重型动力触探修正后击数,(,击,/10cm);,a,2,特重型动力触探杆长击数修正系数,可按下表确定。,N120,杆长,L,1,3,5,7,9,10,15,20,25,30,35,40,1,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,2,0.96,0.92,0.91,0.90,0.90,0.90,0.90,0.8
11、9,0.89,0.88,0.88,0.88,3,0.94,0.88,0.86,0.85,0.84,0.84,0.84,0.83,0.82,0.82,0.81,0.81,5,0.92,0.82,0.79,0.78,0.77,0.77,0.76,0.75,0.74,0.73,0.72,0.72,7,0.90,0.78,0.75,0.74,0.73,0.72,0.71,0.70,0.68,0.68,0.67,0.66,13,四、,资料整理与计算,N120,杆长,L,1,3,5,7,9,10,15,20,25,30,35,40,9,0.88,0.75,0.72,0.70,0.69,0.68,0.67,
12、0.66,0.64,0.63,0.62,0.62,11,0.87,0.73,0.69,0.67,0.66,0.66,0.64,0.62,0.61,0.60,0.59,0.58,13,0.86,0.71,0.67,0.65,0.64,0.63,0.61,0.60,0.58,0.57,0.56,0.55,15,0.86,0.69,0.65,0.63,0.62,0.61,0.59,0.58,0.56,0.55,0.54,0.53,17,0.85,0.68,0.63,0.61,0.60,0.60,0.57,0.56,0.54,0.53,0.52,0.50,19,0.84,0.66,0.62,0.60,
13、0.58,0.58,0.56,0.54,0.52,0.51,0.50,0.48,注,:,本表可线性内插取值。,14,四、,资料整理与计算,4.,特重型动力触探的实测击数,也可先按下式换算成相当 于重型动力触探的实测击数后,再按下式进行修正。,N,63.5,=3N,120,-0.5,5.,根据修正后的动力触探击数,应绘制动力触探击数与贯入深度曲线图。,6.,地基土力学分层应根据动力触探击数与贯入深度曲线图,结合场地地质资料进行。由软层,(,小击数,),进入硬层,(,大击数,),时,分层界线应在软层最后一个小值点以下,10cm20cm,处,;,由硬进入软层时,分层界线应在软层第一个小值点以上,10
14、cm20cm,处。,7.,分层后各层动力触探击数平均值的确定,应符合下列要求:,(,1,)在各层土的厚度范围内,划分出地层界面处上、下土层影响击数的范围,中间部分称为该层的有效厚度,Hh,。,15,四、,资料整理与计算,(,2,)在有效厚度范围内,剔除少量击数特殊大值,(,剔除点的数量不应超过有效厚度内测点数的,10%),余留部分为该层动力触探有效击数。,(,3,)重型动力触探击数平均值,N,63.5,取该层动力触探有效击数的算术平均值,:,N,63.5,=N,63.5,/n,式中,n,参加统计的测点数。,8.,有效厚度小于,0.3m,时,动力触探击数平均值可按下列原则确定:,(,1,)当上、
15、下均为击数较小的土层时,N,63.5,可取该层土触探击数的最大值,(N,63.5,)max,。,(,2,)当上、下均为击数较大的土层时,N,63.5,小于或等于该层土触探击数的最小值,(N,63.5,)min,。,16,四、,资料整理与计算,9.,黏性土地基的基本承载力,0,当贯入深度小于,4m,时,可根据场地土层的,N,10,按下表确定。,注,:,表内数值可以线性内插。,10.,冲积、洪积成因的中砂,砾砂土地基和碎石类土地基的基本承载力,0,当贯入深度小于,20m,时,可根据场地土层的,N,63.5,按下表确定。,N,10,(,击,/30cm,),15,20,25,30,0,100,140,
16、180,220,17,四、,资料整理与计算,N,63.5,(,击,/10cm,),3,4,5,6,7,8,9,10,12,14,中砂,砾砂土,12,150,180,220,260,300,340,380,-,-,碎石类土,140,170,200,240,280,320,360,400,480,540,N,63.5,(,击,/10cm,),16,18,20,22,24,26,28,30,35,40,碎石类土,600,660,720,780,830,870,900,930,970,1000,18,四、,资料整理与计算,11.,基本承载力用于设计时,应进行基础宽度及埋深的修正。修正公式应符合现行,铁
17、路桥涵地基和基础设计规范,TB10093,中有关规定,公式中的修正系数可根据地基土的,N,63.5,值按下表确定,土的,类型,系数,黏性土,砂类土,碎石土,Q4,的冲、洪积土,Q3,及以前的冲、洪积土,残积土,粉砂,细砂,中砂,砾砂粗砂,碎石土,圆砾土,角砾土,卵石土,IL,0.5,IL,0.5,中密,密实,中密,密实,中密,密实,中密,密实,中密,密实,中密,密实,k1,0,0,0,0,1,1.2,1.2,2,2,3,3,4,3,4,3,4,k2,2.5,1.5,2.5,1.5,2,2.5,3,4,按表,8.4.11-2,取值,19,四、,资料整理与计算,注,:,1.,节理发育或很发育的风化
18、岩石,k1,、,k2,可参照碎石类土的修正系数,但对已风化成砂、土状者,则取用砂类土、黏性土的修正系数。,2.,稍密状态的砂类土和松散状态的碎石类土,k1,、,k2,值可采用表列中密值的,50%3.,冻土的,k1=0,、,k2=0,。,12.,黏性土地基极限承载力,p,u,当贯入深度小于,4m,时,可根据场地土层的,N,10,按下表确定。,N,63.5,4,4,6,6,10,10,15,15,20,20,25,25,32,32,40,40,K2,1,2,3,4,5,6,7,8,9,20,四、,资料整理与计算,注,:,表内数值可以线性内插,;p,u,的变异系数为,0.291,。,13.,冲积、洪
19、积成因的中砂,砾砂土地基和碎石类土地基的极限承载力,p,u,当贯入深度小于,20m,时,可根据场地土层的,N,63.5,按下表确定。,N,10,(击,/30cm,),15,20,25,30,p,u,180,260,330,400,N,63.5,(击,/10cm,),3,4,5,6,7,8,9,10,12,14,中砂砾砂土,240,300,360,440,520,600,680,760,-,-,碎石土,320,390,450,550,645,740,835,930,1100,1250,N,63.5,(击,/10cm,),16,18,20,22,24,26,28,30,35,40,碎石土,1390
20、,1530,1670,1810,1930,2020,2090,2160,2260,2330,21,四、,资料整理与计算,注,:,中砂一砾砂土、碎石类土,P,u,值的变异系数分别为,0.248,和,0.210,。,14.,冲、洪积卵石土和圆砾土地基的变形膜量,E,0,当贯入深度小于,12m,时,可根据场地土层的,N,63.5,按下表取值,15.,碎石类土平均粒径等于或小于,50mm,且最大粒径小于,100mm,时,根据重型动力触探实测击数经杆长修正后击数,N,63.5,按下表确定碎石类土的密实度。碎石类土平均粒径大于,50mm,或最大粒径大于,100mm,时,根据特重型,N,63.5,(击,/1
21、0cm,),3,4,5,6,8,10,12,14,16,E,0,9.9,11.8,13.7,16.2,21.3,26.4,31.4,35.2,39.0,N,63.5,(击,/10cm,),18,20,22,24,26,28,30,35,40,E,0,42.8,46.6,50.4,53.6,56.1,58.0,59.9,62.4,64.3,22,四、,资料整理与计算,动力触探实测击数经杆长修正后击数,N,120,按下表确定碎石类土的密实度。,重型动力触探锤击数,N,63.5,N,63.5,5,5,N,63.5,10,10,N,63.5,20,N,63.5,20,密实度,松散,稍密,中密,密实,特重型动力触探锤击数,N,120,N,120,3,3,N,120,6,6,N,120,11,N,120,11,密实度,松散,稍密,中密,密实,23,