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1、Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong长石Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong
2、Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong云母Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi
3、GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong蒙脱石Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui
4、Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong高岭石Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Chen
5、g Shi Gong碎石土Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong砂土Shui Gong Cheng Shi GongShui Gong Cheng Shi G
6、ongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong粉土Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Go
7、ng Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong粘性土Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng
8、Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong云母Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongSh
9、ui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong（一）推土机施工（一）推土机施工Shui Gong Cheng Shi Go
10、ngShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong水工程施工水工程施工Shui Gong Cheng Shi GongShui Gong Cheng Shi Gong第一章第一章 土石方工程与地基处理土石方工程与地
11、基处理Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl2 2、反铲挖土机、反铲挖土机l 反铲挖土机工作特点：反铲挖土机工作特点：l 是开挖停机面以下的土壤，不需设置进
12、出口通道。适用于开挖管沟和基槽，也可开挖小型基坑。尤其适用于开挖地下水位较高或泥泞的土壤。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong反反铲铲挖挖土土机机传传动动方
13、方式式：有液压传动和机械传动两种。表1-15为机械传动反铲挖土机的主要技术性能及工作尺寸。常用反铲主要技术性能表1-15技术参数符号单位数据土斗容量支杆长度斗柄长度支杆倾角最大挖掘深度最大挖掘半径卸土开始时半径卸土终止时半径卸土开始时高度卸土终止时高度qLL1xHRR1R2H1H2m3mm度mmmmmm0.55.52.8455.569.204.668.102.205.26605.569.203.537.003.106.14Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng
14、 Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl 沟端开挖：挖土机停在沟槽一端，向后倒退挖土，汽车可在两旁装土，此法采用较广。其工作面宽度较大，单面装土时为1.3R，双面装土时为1.7R，深度可达最大挖土深度H。l 沟侧开挖：挖土机沿沟槽一侧直线移动挖土。此法能将土弃于距沟边较远处，可供回填使用。由于挖土机移动方向与挖土方向相垂直所以稳定
15、性较差，而且开挖深度和宽度（一般为0.8R）也较小，也不能很好控制边坡 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl3 3、拉铲挖土机、拉铲挖土机l 拉铲挖土机的
16、工作装置简单，可由起重机改装。拉铲的开挖方式，基本上与反铲挖土机相似拉铲的开挖方式，基本上与反铲挖土机相似，也可分为沟端开挖和沟侧开挖 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng
17、Shi Gong常用拉铲挖土机的主要技术性能，见表1-16。技术参数单位W-501W-1001铲斗容量铲臂长度铲臂倾斜角度最大卸土高度最大卸土半径最大挖掘半径侧面挖掘深度正面挖掘深度m3m度mmmmm0.51.010131316303.510.011.14.47.3455.58.310.23.85.6305.312.514.36.610.0458.010.413.25.97.8304.212.814.45.88.5456.910.813.24.97.4305.715.417.58.012.2459.012.916.27.19.6Shui Gong Cheng Shi GongShui Gong
18、 Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl4 4、抓铲挖土机、抓铲挖土机l 抓铲挖土机一般由正、反铲液压挖土机更换铲土斗换上合瓣式抓斗而成，也可由履带式起重机改装。可用以挖掘面可用以挖掘面积较小，深度较大的沟槽沉井或独立柱积较
19、小，深度较大的沟槽沉井或独立柱基的基坑，最适宜于进行水下挖土，基的基坑，最适宜于进行水下挖土，如放置在驳船上，开挖地面水取水构筑物基础水下土石方。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong C
20、heng Shi Gongl图1-38为合瓣铲挖土机示意图，图1-39为拉铲产用三角形挖土方法。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Ch
21、eng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong单斗挖土机生产率计算：单斗挖土机纯工作小时生产率Ph可按下列公式计算：（m3/h）(1-43)式中：q土斗容量（m3）n每分钟挖土次数；Tp挖土
22、机每次循环延续时间（s）K系数，一般为0.60.87Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong单斗挖土机台班生产率Pd按下式计算：（1-44）式中：KB工作时间利
23、用系数：在向汽车装土时，KB为0.680.72在侧向堆土时，KB为0.780.88挖爆破后的岩石时，KB为0.60；土斗容量愈小，KB值愈低。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Che
24、ng Shi Gongl（二）多斗挖土机施工（二）多斗挖土机施工l1、多斗挖土机的性能及其开挖方式l 多斗挖土机又称挖沟机、纵向多斗挖土机。与单斗挖土机比较，它有下下列列优优点点：挖土作业是连续的，在同样条件下生产率较高；开挖每单位土方量所需的能量消耗较低；开挖沟槽的底和壁较整齐；在连续挖土的同时，能将土自动卸在沟槽一侧。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Sh
25、i GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl挖沟机不宜开挖坚硬的土和含水量较大的土。它宜于开挖黄土，粉质粘土等。l挖沟机由工作装置、行走装置和动力、操纵及传动装置等部分组成。挖沟机的类型，按工作装置分为链斗式和轮斗式两种。按卸土方法分为装有卸土皮带运输器的和未装卸土皮带运输器的两种。通常挖沟机大多装有皮带运输器。行走装置有履带式、轮胎式和履带轮胎式三种。动力一般为内燃机。Shui Gong Cheng Shi GongShui Gon
26、g Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl链斗式挖沟机的构造如图1-40 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShu
27、i Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl挖沟机土斗装设有围绕斗架的无极斗链上。土斗前端用铰链连接于斗链，后端自由地悬挂。斗架位于机械后部，前端有钢索连接于升降斗架的卷筒，并有滚子嵌在凹槽形的导轨内。开动卷筒，通过钢索使斗架沿导轨升降，改变沟槽开挖深度。l动力装置通过传动机构使主动链轮转动，带动斗链转动，于是
28、没入土中的土斗切土。当土斗上升至主动链轮处，其后端即与斗链分开而卸土，土沿堆土板滑下，由装设在堆土板下方的皮带运输器卸至机器一侧。皮带运输器由一马达带动，其运行的方向与挖沟机的开行方向垂直。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Che
29、ng Shi GongShui Gong Cheng Shi Gongl沟槽开挖宽度与土斗宽度相同。为加大开挖宽度，可在土斗两旁各装设一铸造钢制的括耳，使开挖宽度由0.8m加大至1.1m。如要增加挖深，可更换较长的斗架。l挖沟机开挖的沟槽断面一行贿受贿为直槽，但更换工作装置（图1-41）后，也可挖成梯形槽。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongSh
30、ui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Chen
31、g Shi GongShui Gong Cheng Shi Gongl轮斗式与链斗式挖沟机的主要区别，在于前者的土斗是固定在圆形的斗轮上，斗轮旋转使土斗连续挖土。当土斗旋升到斗轮顶点时，土即卸至皮带运输器上被运出卸在沟槽一侧。斗轮通过钢索升降改变挖土深度。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui
32、 Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl 当地面具有较大横向坡度时，采用可调节轮轴的挖沟机（图1-42）Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Go
33、ng Cheng Shi GongShui Gong Cheng Shi Gong2、挖沟机的生产率计算挖沟机生产率Ph可按下式计算：（m3/h）（1-45）式中：n土斗每分钟挖掘次数；q土斗容量（L）；Kc斗的充盈系数；KP土的最初可松性系数；K土的开挖难易程度系数；KB时间利用系数。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Ch
34、eng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gong第四节 土方施工发生塌方与流砂的处理 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui
35、Gong Cheng Shi GongShui Gong Cheng Shi Gongl在土石方开挖施工中，由于处理不当，常会发生边坡塌方和产生流砂现象。l（一）边坡塌方（一）边坡塌方l沟槽、基坑边坡的稳定，主要是由土体的内摩阻力和粘结力来保持平衡的。当土体失去平衡，边坡就会塌方。边坡塌方会引起人身事故，同时也妨碍施工正常进行，严重塌方还会危及附近建筑物的安全。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Go
36、ngShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong
37、Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Go
38、ngl发生边坡塌方的原因发生边坡塌方的原因有以下几点：l1、基坑、沟槽边坡放坡不足，边坡过陡，使土体本身的稳定性不够。在土质较差开挖深度较大时，常遇到这种情况；l2、降雨、地下水或施工用水渗入边坡，使土体抗剪能力降低，这是千万塌方的主要原因；l3、基坑、沟槽上边缘附近大量堆土或停放机具；或因不合理的开挖坡脚及受地表水、地下水冲蚀等，增加了土体负担，降低了土体的抗剪强度而引起滑坡和塌方等。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong
39、 Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl针对上述分析，为了防治滑坡和塌方，应采取如下措施：注意地表水、地下水的排除；严格按不同土质放坡规定，放足边坡；当开挖深度大，施工时间长、边坡有机具或堆置材料等情况，边坡应平缓；当因受场地限制，或因放皮增加土方量过大，则应采用设置支撑的施工方法。Shui Gong Cheng Shi GongShui Gong Cheng Sh
40、i GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl（二）流砂的防治（二）流砂的防治l 流砂现象流砂现象：在沟槽、基坑开挖低于地下水位，且采用坑（槽）内抽水时，有时发生坑底下面的土形成流动状态，随地下水涌进坑内而产生流砂。流砂严重时会引起沟槽、基坑边坡塌
41、方、滑坡，如附近有建筑物，会因地基被掏空而使建筑物下沉、倾斜，甚至倒塌。因此，在土方施工时必须消除地下水的影响。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl（二）
42、流砂的防治（二）流砂的防治l 流砂现象流砂现象：在沟槽、基坑开挖低于地下水位，且采用坑（槽）内抽水时，有时发生坑底下面的土形成流动状态，随地下水涌进坑内而产生流砂。流砂严重时会引起沟槽、基坑边坡塌方、滑坡，如附近有建筑物，会因地基被掏空而使建筑物下沉、倾斜，甚至倒塌。因此，在土方施工时必须消除地下水的影响。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongSh
43、ui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl 流砂防治的措施流砂防治的措施：水下挖土法（此法在沉井不排水挖土下沉施工中常用）、打钢板桩法、地下连续墙法（施工工艺复杂，成本高，多用于高层建筑、工业建筑地下工程及水利工程）等，而采用较广并较可靠的方法是人工降低地下水法。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Go
44、ngShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl（三）滑坡体施工中的作业方法（三）滑坡体施工中的作业方法l首先应对滑坡区的地质资料作好调查研究。据此正确选择施工程序，并拟定合理的施工方法，确定保持滑坡体稳定的边坡坡度，预防滑坡发生。在进行开挖和填方时，应注意以下几点：Shui Gong Cheng Shi GongShui Gong Cheng Shi
45、 GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl1、在靠近滑坡边沿处开挖土方l一般不应切割滑坡体的坡脚，当必须切割坡脚时，应按切割深度，将坡脚随原自然坡度由上向下削坡，逐渐挖至要求的坡脚深度，如图1-43所示 Shui Gong Cheng Shi G
46、ongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl 2、在滑坡体上挖填土方l（1）当需在滑坡内挖方时，应遵守由上至下的开挖程序，如滑坡土方量不大，所有滑坡体应全部挖除；l （2）在滑坡体上进行填方时，应遵守由下
47、至上的施工顺序。此外，尚须在滑坡体的坡脚处，填筑能抵抗滑坡体下滑的土体。如图1-43（b）所示的土体I，图中土体II为填土区域，施工程序是由下向上填筑 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gon
48、g Cheng Shi Gong第五第五节 沟槽及基坑支撑沟槽及基坑支撑l支撑是防止沟槽土壁坍塌的一种临时性挡土结构，由木材或钢材做成。l支撑的荷载就是原土和地面荷载所产生的侧土压力。l沟槽支撑与否应根据土质、地下水情况、槽深、槽宽、开挖方法、排水方法、地面荷载等因素确定。Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi
49、 GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl支撑结构应满足下列要求支撑结构应满足下列要求：l1、牢固可靠，进行强度和稳定性计算和校核。支撑材料要求质地和尺寸合格，保证施工安全。l2、在保证安全的前提下，节纸用料，宜采用工具式钢支撑。l3、便于支设和拆除及后续工序的操作。l 为了做到上述要求，支撑材料的选用、支设和使用过程，应严格遵守施工操作规程 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Go
50、ngShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Cheng Shi Gongl一、支撑种类及其适用条件一、支撑种类及其适用条件 l 沟槽支撑形式：沟槽支撑形式：有横撑、竖撑和板桩撑，开挖较大基坑时还采用锚碇式支撑等 Shui Gong Cheng Shi GongShui Gong Cheng Shi GongShui Gong Ch