土方工程
一、土方基础概念 | Earthwork Fundamentals
二、土方作业 | Earthwork Operations
三、土壤与地基 | Soil & Subgrade
四、压实与检测 | Compaction & Testing
五、沟槽与基坑 | Trenches & Excavations
六、爆破与石方 | Blasting & Rock Excavation
Earthwork Operations — Cut, Fill & Compaction Control
Huang, we're starting the mass earthwork today. The survey crew set the grade stakes yesterday. Walk me through the cut and fill plan for this quadrant.
黄工，今天开始大面积土方了。测量队昨天打了标高桩。给我过一遍这个 区的挖填方案。
黄工: This is Quadrant A — the substation platform. Total area is about 5 acres. Design finished grade is elevation 100.50 meters. Existing ground varies from 98.20 to 102.80 meters.
这是A区——升压站平台。总面积大约5英亩。设计完工标高100.50米。原有 地形从98.20到102.80米不等。
So we need to cut the high spots and fill the low spots. Net cut is about 8,500 cubic meters, net fill is about 6,200 cubic meters. We have a surplus of 2,300 cubic meters of cut material. That goes to the spoil area on the north side.
所以我们要挖高处，填低处。净挖方约8,500立方米，净填方约6,200立方 米。剩余2,300立方米挖方料运到北侧的弃土场。
What about the topsoil? We need to strip that first.
表土呢？得先清表。
黄工: Correct. Topsoil stripping is 6 to 8 inches deep, stockpiled separately at the southwest corner. We'll use it later for landscaping and erosion control. Not mixed with the fill material.
对。清表深度6到8英寸，单独堆在西南角。后面用来绿化和防冲刷。不和 填筑料混在一起。
Good. And the fill material — is it suitable? We're not putting organic soil or expansive clay under a substation platform.
好。填筑料——适用吗？我们不能把有机土或膨胀黏土填到升压站平台下面。
黄工: The geotech report says the site soil is mostly sandy silt with some gravel — classified as SM per USCS. Good bearing capacity, low expansion potential. We tested three samples already. CBR is 15% minimum — well above the 8% spec.
地勘报告说现场土以砂质粉土为主，含一些砾石——统一土分类法归为SM类。 承载力好，膨胀性低。已经测了三个样品。CBR最低15%——远超8%的指标。
OK. Let's talk compaction. What's your spec?
好。谈谈压实。你的指标是什么？
黄工: 95% of modified Proctor density for the top 12 inches below the platform, 92% for the fill below that. Maximum dry density is 120 pcf, optimum moisture content is 12.5% ±2%.
平台以下顶部12英寸修正普氏密度的95%，再往下92%。最大干密度120磅每 立方英尺，最佳含水率12.5%±2%。
Sam, you're doing the density testing. What's the schedule?
Sam，你负责密度检测。怎么安排？
One field density test per 500 square meters per lift. We're using the nuclear density gauge — calibrated this morning. Each lift is 8 inches loose, compacted to 6 inches. If it doesn't hit 95%, we re-roll and test again.
每层每500平方米一个现场密度检测。我们用核子密度仪——今早刚校过。 每层松铺8英寸，压实到6英寸。没达到95%的话，重新碾压再测。
黄工: I'll also check the moisture. If it's too dry, we water the fill with the water truck before rolling. If it's too wet, we disc and aerate it.
我也会查含水率。太干了就用水车洒水再碾压。太湿了就翻松晾晒。
(A dump truck arrives) Jim, the first load of fill is here. I'll direct the dozer to spread it. We'll keep the lift thickness to 8 inches max.
（自卸车到了）Jim，第一车填土到了。我指挥推土机推开。松铺厚度控制 在8英寸以内。
Good. Remember — the key to earthwork is layer by layer, test before you proceed. Never place the next lift until the current lift passes compaction. Let's get moving.
好。记住——土方工程的关键是层层推进，先检后进。当前层压实没通过， 绝不能铺下一层。开工吧。
Trench Excavation — Safety and Shoring
He Gong, I see you're about to start the trench for the fire water line. What's the depth, and what's your protection plan?
何工，我看到你们准备开挖消防水管沟了。深度多少？你的防护方案是什 么？
何工: The trench is 8 feet deep and 3 feet wide at the bottom. We're in Type B soil — sandy silt with some cohesion. The trench runs about 200 feet along the south side of the substation.
沟深8英尺，底宽3英尺。土质是B类土——砂质粉土，有一定黏性。沿升压 站南侧长约200英尺。
8 feet deep in Type B soil. Per OSHA, the maximum allowable slope for Type B soil is 1:1 — 45 degrees. Are you sloping or using a trench box?
8英尺深B类土。按OSHA要求，B类土最大允许坡度是1:1——45度。你们是放 坡还是用沟槽支护箱？
何工: We can't slope — we're too close to the existing cable duct bank on one side. So we're using a trench box. It's a 6-foot-high steel shield with hydraulic struts, rated for 8-foot depth in Type B soil.
放不了坡——一侧离既有电缆管束太近了。所以我们用沟槽支护箱。6英尺 高的钢质防护箱，带液压支撑，额定B类土8英尺深度。
Let me inspect the trench box. Show me the manufacturer's tabulated data — I need to see the depth rating and soil type rating.
我检查一下沟槽支护箱。给我看出厂铭牌数据——我要看深度额定值和土质 额定值。
何工: Here's the data plate. Rated for Type B and C soils up to 10 feet depth. The hydraulic struts were pressure-tested this morning — all holding at 3,000 psi. We have the inspection tag on each strut.
这是铭牌。额定B类和C类土，最深10英尺。液压支撑今早做了压力测试—— 全部保压在3,000 psi。每个支撑上都有检验标签。
Good. The trench box needs to extend at least 18 inches above the top of the trench. Since your trench is 8 feet and the box is 6 feet, you need another 2 feet of extension. What's your plan for that?
好。沟槽箱需高出沟槽顶部至少18英寸。你的沟8英尺深、箱6英尺高，还 需要2英尺的延伸段。这怎么解决？
何工: We'll stack two boxes — a 6-foot and a 4-foot. Total 10 feet, plenty of stick-up. The crew is picking up the second box from the yard now.
我们叠两个箱——一个6英尺、一个4英尺。总共10英尺，足够高出地面了。 班组正在从堆场取第二个箱。
OK. What about the spoil pile? Keep it at least 2 feet back from the edge of the trench. I don't want the weight of the spoil causing a cave-in.
好。弃土堆呢？至少离沟槽边缘2英尺。我不想弃土的重量引起塌方。
(from the excavator) I'll place the spoil on the north side. The trench box gets lowered in as I dig. We'll advance about 10 feet at a time — dig, set box, dig, slide box forward.
（从挖掘机上喊）我把弃土放在北边。沟槽箱随挖随下。每次推进约10英 尺——挖、放箱、再挖、箱往前滑。
That's the right sequence. But remember — nobody goes in the trench while you're setting or moving the box. Only after the box is fully in place and inspected.
顺序对的。但记住——放箱或移箱的时候，任何人不得进入沟槽。只等箱完 全就位并检查后才准进。
Also, I want a ladder at both ends — one for entry, one for emergency egress. And a gas detector at the bottom. You're 8 feet deep, that's a confined space.
还有，两端各设一个梯子——一个进人用，一个紧急逃生用。沟底放一台气 体检测仪。8英尺深，这是受限空间。
何工: We have all that ready. Gas monitor, two ladders, rescue tripod with winch standing by. The crew has been briefed this morning. JSA is signed and posted at the entry point.
这些我们都准备好了。气体检测仪、两个梯子、配绞盘的救援三脚架放在 边上。班组今早刚交过底。作业安全分析签好了贴在入口处。
Alright. I'm satisfied. But I'll be checking on you throughout the day. Any sign of sloughing, cracking, or water in the trench — stop work and call me immediately.
好。我认可了。不过我今天全天会来抽查。沟槽里出现任何剥落、裂缝或 渗水——立刻停工，马上电话叫我。
何工: Understood. Safety first. Thanks, Frank.
明白。安全第一。谢谢Frank。