2#竖井人工挖探孔专项施工方案

合集下载

2是什么意思

2是什么意思

《*2是什么意思》
“*2”这个符号在计算机世界里有着特殊的意义,它的意思是“乘方”,也就是说它表示
某个数字的平方,比如2*2就表示2的平方,也就是4,以此类推,3*3就表示3的平方,也就是9。

在数学中,乘方是一种常见的运算,它表示某个数字的幂次方,也就是说,它表示一
个数字乘以它自己的次数,比如2的3次方就表示2乘以2乘以2,也就是8。

在计算机世界中,乘方的符号一般都是“*2”,在程序中也会使用到这个符号,比如在
C语言中使用的pow()函数就是用来计算乘方的,它的参数就是带有*2的乘方表达式,比
如pow(2,3)就表示2的3次方,也就是8。

总之,“*2”这个符号在计算机世界里表示乘方运算,它可以用来表示一个数字的幂次方,也可以用来表示某个数字的平方,它在程序中也可以被应用到很多地方,是一个非常
常见也非常有用的符号。

2用英语怎么写

2用英语怎么写

1.2用英文怎么写2的英文是two。

词汇分析音标:英[tuː] 美 [tu]释义:n. 两个adj. 两个的num. 二短语Two Whatevers 两个凡是Two Women 烽火母女泪;两个女人;战地两女性;两女Two Cops 特警冤家;两个警察;锄暴特警;两个刑警Two Soldiers 两个士兵;两名士兵;同胞兄弟;幽默英语故事两名士兵Two Lamps 两盏巨灯Perfect Two 新天生一对;天生一对;咸菜贤才大贤永才例句1、They teamed Class One with Class Two.他们将一班和二班编成一队。

我们用两个师包围了这座城市。

3、We talked about two hours, but he hedged over my questions.我们用两个师包围了这座城市。

4、Working together for two months welded them into a group.在一起工作两个月使他们形成了一个团体。

5、He died two months ago.他两个月前去世了。

2.2的英文怎么写2的英文是two。

two英 [tu:] 美 [tu]n. 两个;两个东西;两点钟;一对;adj. 两个的;我同;num. 两个;第二;二;双语例句1. It's a long way to go for two people in their seventies.对于两个七十几岁的人来说,这段路太远了。

他在那儿的时候体重下降了2英石。

3. I undid the bottom two buttons of my yellow and grey shirt.我解开了自己黄灰相间的衬衫上最下面的两个纽扣。

4. It would be difficult to find two men who were more dissimilar.很难找到彼此间差异更大的人了。

我的揪痧瘾(2020、2)

我的揪痧瘾(2020、2)

我的揪痧瘾(2020、2)我的揪痧瘾医⽣在线⽹2008/12/1709:22来源:我叫⼩美,⼩时侯经常看见⼈们揪痧,但从没体验过,是在我⾼中后,有⼀次重感冒,吃药也不见好,晚上妈妈说我给你揪揪痧吧,我没说什么,妈妈就在我脖⼦后边揪开了,刚开始还不是很疼,但随着吧吧的揪痧声,妈妈的⼿劲越来越⼤,我疼的乱叫,妈妈说痧很重,必须得揪透了才⾏,不管我怎么喊叫,妈妈就是不停⼿,⽽且我越动她就越⽤⼒,我只好咬着⽛强忍着,妈妈从脖⼦⼀直连着揪到肩膀,⼜把整个后背都揪了个遍.我以为终于揪完了,可妈妈⼜在我前胸揪了起来,特别疼,我眼泪都出来了,可妈妈就是不⼿软,揪了⼀个多⼩时,只到把我上⾝揪的紫⿊紫⿊的没⼀块好地⽅才罢⼿,揪出我⼀⾝汗,可别说,揪完我就特轻松舒服了.从此以后我⼀感冒发烧的就让妈妈给揪,我还真喜欢上了这种痛并很快乐的感觉.隔⼀段时间不舒服了就让⽼妈给揪揪全⾝.后来结婚了,我很希望⽼公能给我好好揪⼀次,可他不喜欢揪,总也不给我揪,⽽且他不舒服也不让我给他揪.有⼀次我发烧,晚上实在难受的不⾏,让⽼公给揪揪他怎么也不肯,后来看我不⾏就给我在后背刮了刮痧,可我总觉的没有揪痧的过瘾.⽣完孩⼦后我落下了腰疼的⽑病,去诊所拔了⼏次罐后,感觉挺管⽤,⽼公看我腰疼的直不起来也很着急,后来我治我的腰学会了拔罐,经常在我腰疼的时候给我拔罐、⾛罐、按摩、揪痧等,现在⽼公拔罐揪痧的技术很⾼,不光给我整治腰,在我感冒的时候也会给我揪痧、拔罐,现在我⼜可以感受揪痧拔罐了。

在⽼公的经常拔罐按摩下我的腰疼的次数少多了。

在我的影响下⽼公也爱上了揪痧拔罐,在他不舒服的时候,我也会很体贴的为他揪痧拔罐,他也没那么怕疼了。

现在⽼公⼀不舒服就主动让我给他揪痧。

我们两经常是旧痕未去⼜添新伤,但我们都很快乐!⽼公有⼀次在外地感冒了给我打电话说:“⽼婆我越来越离不开你了,你要在我⾝边就可以给我揪痧了,我真的好难受。

”我说:“你以前不是怕疼⽼不让揪吗?现在想起我的好了?你到外边诊所拔拔罐吧!回来我给你揪。

2020新译林版高中英语选修第二册unit2课文翻译(英汉对照)

2020新译林版高中英语选修第二册unit2课文翻译(英汉对照)

Unit2Building the future构建未来ReadingRenewable energy:a gift for the future可再生能源:给未来的礼物There was once a village surrounded by fertile fields with farmers tending their crops and farm animals grazing lazily below a mighty mountain.Then coal was discovered,and soon titanic-sized earth-digging machines circled the village. Villagers eagerly accepted the high-paid jobs the mining company provided,bringing a temporary economic boom.Meanwhile,the machines cut through everything in their path to access the coal buried beneath.Many years later,all that remained was a deserted village and an enormous hole.从前有一个村庄,四周都是肥沃的田地,农民们在那里照料着他们的庄稼,家畜在巍峨的山下懒洋洋地吃草。

后来,人们发现了煤,很快,巨型挖土机就环绕了整个村子。

村民们急切地接受了矿业公司提供的高薪工作,带来了短暂的经济繁荣。

与此同时,采煤机穿过路上的一切障碍物来开采埋在地下的煤炭。

许多年后,只剩下一个废弃的村庄和一个巨大的洞。

The scenario is tragic,but it only partly describes the damaging effects fossil fuels have on the environment when they are mined.Actually,once burnt,they produce a large quantity of carbon dioxide,which in turn traps heat and causes global warming.Humans are clearly facing a critical moment,so a move towards clean, renewable energy is inevitable.Renewable energy sources,which include solar,wind, hydroelectric,tidal,biomass and geothermal energy,are perfect alternatives to fossil fuels.One of the reasons is that their carbon dioxide emissions tend to be lower.A study found that renewable energy sources emit about50g or less of carbon dioxide per kilowatt-hour over their lifetime,compared to about1,000g for coal.Besides, fossil fuels are non-renewable,whose reserves are estimated to dry up one day in the future.In contrast,renewable energy sources are basically inexhaustible and will be available to us for a few billion more years if our planet remains safe and healthy.这种情况是悲惨的,但它只是部分描述了化石燃料在开采时对环境的破坏性影响。

周边地面 2

周边地面 2

周边地面——对没有地下室的建筑指底层房间外墙内侧两米范围内的地面。

对有地下室埋墙的建筑,指从室外地面和埋墙的交线算起向下两米内为周边地面。

非周边地面——对没有地下室的房间指底层地面中周边地面以外的部分。

有地下室埋墙的建筑,非周边地面指埋墙和地面面积的和减去从室外地面和埋墙交线算起向下两米的面积。

关于周边地面和非周边地面的几点说明1.周边地面和非周边地面的定义周边地面指距外墙内表面2m以内的地面,其余部分划为非周边地面。

位于室外地面以下的外墙(地下室外墙)应从与室外地面相平的墙壁算起,往下2m范围内为周边地面,其余部分划为非周边地面。

2.节能标准中对周边地面和非周边地面传热阻的计算《民用建筑节能设计标准》(采暖居住部分)JGJ26-95和《公共建筑节能设计标准》GB50189-2005对周边地面和非周边地面热阻采用了不同的计算方法,应分别对待。

A) 居住建筑:换热阻计算依据来源于《供热工程》(贺平孙刚编著)。

由于室内热量通过地面传到室外的路程长短不同,即热阻值不同,靠近外墙的室内地面,距离室外路程短,热阻值小,传热量大,反之远离外墙的地面热阻值大,传热量小,离外墙8m以远的地面,传热量基本不变。

基于上述情况,在工程上一般采用近似方法计算,把地面沿外墙平行的方向分成四个计算地带(每2m为一个地带,8m以外地面按第四地带考虑),如图1示。

1) 对于贴土非保温地面(组成地面的各层材料导热系数λ都大于1.16W/m?℃),各地带的传热系数和换热阻如下:周边地面传热系数限值为0.52 W / m2·℃地区,考虑到非保温地面第一地带(周边地面)的传热系数为0.47 W / m2·℃,小于限值0.5 2W / m2·℃,可不做保温;非周边地面(第二、三、四地带)不做保温时传热系数最大值为0.23 W / m2·℃,小于限值0.3 W / m2·℃,同样也能满足非周边地面限值的要求。

托福TPO42阅读Passage2原文文本+题目+答案解析

托福TPO42阅读Passage2原文文本+题目+答案解析

为了帮助大家高效备考托福,为大家带来托福TPO42阅读Passage2原文文本+题目+答案解析,希望对大家备考有所帮助。

Explaining Dinosaur Extinction Dinosaurs rapidly became extinct about 65 million years ago as part of a mass extinction known as the K-T event,because it is associated with a geological signature known as the K-T boundary,usually a thin band of sedimentation found in various parts of the world(K is the traditional abbreviation for the Cretaceous,derived from the German name Kreidezeit).Many explanations have been proposed for why dinosaurs became extinct.For example,some have blamed dinosaur extinction on the development of flowering plants,which were supposedly more difficult to digest and could have caused constipation or indigestion—except that flowering plants first evolved in the Early Cretaceous,about 60 million years before the dinosaurs died out.In fact,several scientists have suggested that the duckbill dinosaurs and homed dinosaurs,with their complex battery of grinding teeth,evolved to exploit this new resource of rapidly growing flowering plants Others have blamed extinction on competition from the mammals,which allegedly ate all the dinosaur eggs—except that mammals and dinosaurs appeared at the same time in the Late Triassic,about 190 million years ago,and there is no reason to believe that mammals suddenly acquired a taste for dinosaur eggs after 120 million years of coexistence Some explanations(such as the one stating that dinosaurs all died of diseases)fail because there is no way to scientifically test them,and they cannot move beyond the realm of speculation and guesswork. This focus on explaining dinosaur extinction misses an important point the extinction at the end of the Cretaceous was a global event that killed off organisms up and down the food chain.It wiped out many kinds of plankton in the ocean and many marine organisms that lived on the plankton at the base of the food chain.These included a variety of clams and snails,and especially the ammonites,a group of shelled squidlike creatures that dominated the Mesozoic seas and had survived many previous mass extinctions.The K-T event marked the end of the marine reptiles,such as the mosasaurs and the plesiosaurs,which were the largest creatures that had ever lived in the seas and which ruled the seas long before whales evolved.On land,there was also a crisis among the land plants,in addition to the disappearance of dinosaurs.So any event that can explain the destruction of the base of the food chain(plankton in the ocean,plants on land)can better explain what happened to organisms at the top of the food chain,such as the dinosaurs.By contrast,any explanation that focuses strictly on the dinosaurs completely misses the point The Cretaceous extinctions were a global phenomenon,and dinosaurs were just a part of a bigger picture. According to one theory,the Age of Dinosaurs ended suddenly 65 million years ago when a giant rock from space plummeted to Earth.Estimated to be ten to fifteen kilometers in diameter,this bolide(either a comet or an asteroid)was traveling at cosmic speeds of 20-70 kilometers per second,or 45,000-156,000 miles per hour.Sucha huge mass traveling at such tremendous speeds carries an enormous amount of energy.When the bolide struck this energy was released and generated a huge shock wave that leveled everything for thousands of kilometers around the impact and caused most of the landscape to burst into flames.The bolide struck an area of the Yucatan Peninsula of Mexico known as Chicxulub,excavating a crater 15-20 kilometers deep and at least 170 kilometers in diameter.The impact displaced huge volumes of seawater,causing much flood damage in the Caribbean.Meanwhile,the bolide itself excavated 100 cubic kilometers of rock and debris from the site,which rose to an altitude of 100 kilometers.Most of it fell back immediately,but some of it remained as dust in the atmosphere for months.This material,along with the smoke from the fires,shrouded Earth,creating a form of nuclear winter.According to computerized climate models,global temperatures fell to near the freezing point,photosynthesis halted,and most plants on land and in the sea died.With the bottom of the food chain destroyed,dinosaurs could not survive. paragraph 1 Dinosaurs rapidly became extinct about 65 million years ago as part of a mass extinction known as the K-T event,because it is associated with a geological signature known as the K-T boundary,usually a thin band of sedimentation found in various parts of the world(K is the traditional abbreviation for the Cretaceous,derived from the German name Kreidezeit).Many explanations have been proposed for why dinosaurs became extinct.For example,some have blamed dinosaur extinction on the development of flowering plants,which were supposedly more difficult to digest and could have caused constipation or indigestion—except that flowering plants first evolved in the Early Cretaceous,about 60 million years before the dinosaurs died out.In fact,several scientists have suggested that the duckbill dinosaurs and homed dinosaurs,with their complex battery of grinding teeth,evolved to exploit this new resource of rapidly growing flowering plants Others have blamed extinction on competition from the mammals,which allegedly ate all the dinosaur eggs—except that mammals and dinosaurs appeared at the same time in the Late Triassic,about 190 million years ago,and there is no reason to believe that mammals suddenly acquired a taste for dinosaur eggs after 120 million years of coexistence Some explanations(such as the one stating that dinosaurs all died of diseases)fail because there is no way to scientifically test them,and they cannot move beyond the realm of speculation and guesswork. 1.In paragraph 1,why does the author include a discussion of when flowering plants evolved? 【事实信息题】 A.To help explain why some scientists believe that the development of flowering plants led to dinosaur extinction。

2的书写方法

2的书写方法

2的书写方法在日常生活中,我们经常会涉及到数字2的书写。

无论是在学习、工作还是生活中,正确的书写方法都是非常重要的。

下面,我们就来详细了解一下数字2的书写方法。

首先,我们要明确数字2的基本形态。

数字2是阿拉伯数字中的一个,它的基本形态是一个弯曲的弧线,上面有一个小圆圈。

这是我们最常见的数字2的书写形式,也是最标准的书写形式。

在书写时,我们需要注意保持数字2的整体形状,保持圆润、匀称,不要出现歪斜、变形等情况。

其次,我们要注意数字2的书写顺序。

在书写数字2时,一般是从上到下、从左到右的书写顺序。

首先画出数字2的上半部分的曲线,然后再画下半部分的曲线,最后在上半部分的曲线上方画一个小圆圈。

这样的书写顺序可以帮助我们更好地掌握数字2的书写方法,保持数字的整体形状和美观度。

除了基本形态和书写顺序外,我们还需要了解数字2的书写规范。

在正式的文件、文书、报告中,数字2的书写需要符合一定的规范。

一般来说,数字2要与其他数字保持一致的字体、大小和风格,以保持整个文档的统一性和美观度。

在手写时,我们也需要注意字迹工整、规范,避免出现潦草、模糊的情况。

此外,数字2的书写还需要注意与其他数字的区分。

在一些情况下,数字2可能会与字母z混淆,因此在书写时要特别小心,确保数字2的书写清晰可辨,不会引起误解。

总的来说,正确的数字2的书写方法对我们的学习、工作和生活都是非常重要的。

通过掌握数字2的基本形态、书写顺序和书写规范,我们能够更好地书写出整洁、规范的数字2,提高书写质量,避免出现错误和混淆。

希望大家能够重视数字2的书写方法,不断提升自己的书写水平,为自己的学习和工作增添亮点。

商务英语阅读教程Unit 2

商务英语阅读教程Unit 2

Unit 2 Multinational CorporationPart I Pre-reading Questions1.Multinational corporations are business entities that operate in more than one country. One typical function is located in one country, while other facilities are located in other countries. In some circles, this type of corporation refers to a multinational enterprise or a transnational corporation.2. Multinational corporations have many branches at home and abroad, and their strategic objectives are oriented to the international market, aiming at maximizing global profits and controlling foreign companies through holdings.3. Corporate social responsibility refers to the responsibility for consumers, the community and the environment while creating profits for shareholders and the staff. The social responsibility of the enterprise requires taking the profit as the goal, emphasizing the concern of the human value in the production process and the contribution to the environment, consumers and society.Part II Extensive ReadingText A Going Global1.主旨归纳:The function of CSR has become more and more important in the world. Manycompanies begin to focus on the establishment of CSR. We are aware of the significance that CSR takes a part in obtaining certification and establishing the brand of a corporation. CSR will continue to expand across the globe if the market remains to open up.2.结构分析Part I The rich countries like Britain, America and Japan focus on different aspects of CSR. (Paras. 1-2)Part II The lead on CSR shifts from the rich world to the big emerging markets. (Paras. 3-13)A.India wants to improve basic services like schools and health care.B.China begins to redefine CSR to gain acceptability and build the brand.C.NGOs make great efforts to manage their reputation.Part III The conclusion: CSR has influenced the emerging countries, which will continue if markets stay open. (Paras. 14-18)3. 难句解析(1) Such differences in priorities are bound to grow in importance as the BRIC countries — Brazil, Russia, India and China — and other emerging markets gain in economic clout and confidence. (Para. 3)随着金砖四国(巴西、俄罗斯、印度和中国)以及其他新兴市场的经济影响力和自信的不断增强,发展优先性方面的差异一定会变得越来越重要。

  1. 1、下载文档前请自行甄别文档内容的完整性,平台不提供额外的编辑、内容补充、找答案等附加服务。
  2. 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
  3. 3、如文档侵犯您的权益,请联系客服反馈,我们会尽快为您处理(人工客服工作时间:9:00-18:30)。

北京地铁3号线一期工程朝阳公园站2#竖井及横通道人工探孔专项方案编制人:审核人:审批人:北京地矿工程建设有限责任公司二〇一六年八月目录一、编制依据 ......................................................................................................................................................... - 2 -二、工程概况 ......................................................................................................................................................... - 2 -三、施工准备 ......................................................................................................................................................... - 3 -3.1作业条件 (3)3.2材质要求 (3)3.3施工器具 (3)3.4班组安排 (3)四、施工方法 ......................................................................................................................................................... - 4 -4.1施工工艺流程 (4)4.2施工方法 (4)五、施工质量保证措施.......................................................................................................................................... - 6 -5.1质量保证措施 (6)5.2施工质量具体保证措施 (7)5.3施工中注意的质量问题 (7)六、雨季、冬季施工措施...................................................................................................................................... - 7 -6.1雨季施工组织管理 (7)6.2雨季施工技术措施 (8)6.3雨季施工安全技术措施 (8)6.4冬季施工措施 (9)七、安全防护措施.................................................................................................................................................. - 9 -7.1安全生产保证体系 (9)7.2安全教育程序 (10)7.3组织安全活动 (10)7.4安全检查 (10)7.5安全生产目标 (11)7.6施工安全措施 (11)7.7现场消防措施 (13)7.8现场保卫措施 (13)八、预防措施 ....................................................................................................................................................... - 13 -8.1预防人工挖探孔桩塌方的措施 (13)8.2地下管线破坏的预防和处理 (14)九、绿色施工保证措施........................................................................................................................................ - 14 -9.1绿色施工管理措施 (14)9.2资源节约措施 (15)9.3环境保护措施 (15)9.4文物保护措施 (16)9.5职业健康及安全措施 (16)一、编制依据1.1《建设工程安全生产管理条例》1.2《地铁降水施工安全管理规定》1.3《降水工程实施阶段安全管理办法》(轨道公司第四项目中心印发)1.4《北京地铁3号线一期工程朝阳公园站2#竖井及横通道降水施工方案》1.5《建筑施工手册(第四版)》1.6《混凝土质量控制标准》(GB50164-92)1.7《建筑工程施工质量验收统一标准》(GB50300-2001)1.8《混凝土检验评定标准》(GBJ107-87)二、工程概况该方案主要针对地铁3号线一期工程朝阳公园站2#竖井的降水工程编制的人工探孔专项施工方案。

朝阳公园站为岛式车站,车站长296.1米,标准段总宽23.1米,有效站台长186米,站台宽14米,拱顶覆土厚度约为5.9~9.3m,底板埋深约25.4m。

主体结构为地下两层直墙三连拱结构(局部三层)。

车站西侧有14号线朝阳公园站,与14号线朝阳公园站之间采用通道换乘,由侧墙、梁、板、柱等构件组成。

车站东端接矿山法区间。

本站附属结构共设3个出入口及3个出入口通道、4个安全出口、2个风道、3个换乘通道。

车站主体采用洞桩法施工,共设置3处施工竖井;出入口均为明挖+暗挖法施工,暗挖段采用CRD法;明挖段采用φ800@1200钻孔灌注桩和φ600@1000钻孔灌注桩。

风道均采用CRD矿山法施工。

团结湖站~朝阳公园站区间采用矿山法施工。

朝阳公园站为M3和M14线的换乘站。

M3线车站位于朝阳公园南路与甜水园街交叉口东侧,沿朝阳公园南路东西向敷设。

朝阳公园南路道路现状宽度51m(规划宽度95m),为双向8车道,两侧各有一非机动车道,路边设人行道,道路设置三道绿化隔离带,该路段交通繁忙,车流量大。

朝阳公园南路北侧为朝阳公园,道路与朝阳公园间有停车场及绿地,南侧从西向东依次为棕榈泉国际公寓2号楼(地上30层,地下2层框支剪力墙结构,基础为平板式筏型基础)、棕榈泉国际公寓5号楼(地上30层,地下2层框支剪力墙结构,基础为平板式筏型基础)、丽水嘉园1号楼。

场地内地下管网密集,包括给水、污水、雨水、电信、电力、热力、煤气等在内的数十条地下管线,纵横交错,非常复杂。

对车站影响较大的管线主要有4500×2750热力管沟、2000×2300电力管沟、74×52电信、φ600给水管等。

2#竖井(中心里程K34+805.253)位于朝阳公园景区管理中心西侧停车场内,竖井埋深27.893m,竖井口地面标高35.670m,井底标高7.777m,场区内地下管线主要有∅600上水管、2000X2300电力管沟,均位于竖井南侧。

横通道垂直下穿的管线主要有:∅400的中压天然气管、4500X2750热力管沟、∅1000雨水管、∅600高压天然气管。

朝阳公园站2#竖井及横通道共布设降水井30眼,其中7眼降水井位于总包围挡内,10眼位于朝阳公园停车场通道上,13眼井位于机动车道和非机动车道上。

所有降水井机械施工前都要采用人工探孔以确定没有地下管线和构筑物。

本区域地质情况相对简单,上部为人工填土,厚0.9~3.3m;其下为粉质粘土、粉土、粉细砂层,再往下为卵砾石层。

本区域稳定水位埋深15.90~16.10m,水位平均年变幅约为2~3m。

三、施工准备3.1作业条件1、人工探孔的井壁支护要根据该地区的土质特点、地下水分布情况,编制切实可行的施工方案,进行井壁支护的计算和设计。

2、开挖前场地完成三通一平。

地上、地下的电缆、管线、旧建筑物、设备基础等障碍物均已排除处理完毕。

各项临时设施,如照明、动力、通风、安全设施准备就绪。

3、熟悉施工图纸及场地的地下土质、水文地质资料。

4、人工探孔操作的安全至关重要,开挖前对施工人员进行全面的安全技术交底;操作前对吊具进行安全可靠的检查和试验,确保施工安全。

3.2材质要求1、水泥:采用42.5级普通硅酸盐水泥。

2、砂:中砂或粗砂,含泥量不大于5%。

3、石子:卵石或碎石,粒径3~7mm,且含泥量不大于2%。

4、水:自来水或不含有害物质的洁净水。

3.3施工器具主要工器具:轱辘、手推车、镐、锹、手铲、钎、线坠、吊桶、溜槽、插钎、粗麻绳、钢丝绳、安全活动盖板、防水照明灯(低压36V、l00W),电焊机、活动爬梯、安全带、弧形工具式钢模四块拼装,卡具、挂钩和零配件。

3.4班组安排成孔开挖以两人为一个小组配合,每小组一天安排2~3个孔进行流水作业,施工时共成立2个小组交叉施工。

四、施工方法4.1施工工艺流程放线定桩位及高程→开挖第一节桩孔土方→支护壁模板→浇筑第一节护壁砼→检查桩位(中心)轴线→架设轱辘→安装吊桶、照明、活动盖板等→开挖吊运第二节桩孔土方(修边)→先拆第一节模板、支第二节护壁模板→浇筑第二节护壁砼→检查桩位(中心)轴线→逐层往下循环作业→原状土。

4.2施工方法1.测量放线:在场地三通一平的基础上,依据测量控制导线的资料和降水井平面布置图,测定井位,并做好护井点。

以中点为圆心,以孔口半径加护壁厚度为半径画出上部(即第一步)的圆周,撒石灰线作为孔口开挖尺寸线。

2.开挖第一节探孔土方:开挖探孔要从上到下逐层进行,先挖中间部分的土方,然后扩及周边,有效地控制开挖探孔的截面尺寸。

每节的高度要根据土质好坏、操作条件而定,一般0.6m~1.0m为宜。

3.支护壁模板:1)护壁模板采用拆上节、支下节重复周转使用。

模板之间用卡具、扣件连接牢固,防止内模因涨力而变形。

不设水平支撑,以方便操作。

2)第一节护壁高出地坪200mm,便于挡土、挡水,护壁厚度取100mm(见附图人工探孔混凝土护壁厚度计算书)。

4.探孔护壁砼:每挖完一节以后要立即浇筑砼。

人工浇筑,人工捣实,砼强度为C15~C20,坍落度控制在80~100mm,确保孔壁的稳定性。

5.检查井位(中心)轴线及标高:每节探孔护壁做好以后,必须将井位十字轴线和标高测设在护壁的上口,然后用十字线对中,吊线坠向井底投设,以半径尺杆检查孔壁的垂直度,发现问题及时修整。

6.架设轱辘:第一节探孔成孔以后,即着手在探孔上口架设轱辘,要求搭设稳定、牢固。

相关文档
最新文档