土木地下工程专业英语翻译
Design of sequential excavation tunneling in weak rocks through ?ndings obtained from displacements based back analysis
Mostafa Sharifzadeh a ,?,Rahman Daraei b ,Mohsen Shari?Broojerdi a
a Department of Mining,Metallurgy and Petroleum Engineering,Amirkabir University of Technology,Tehran,Iran b
Department of Mining Engineering,Sahand University of Technology,Tabriz,Iran
a r t i c l e i n f o Article history:
Received 4December 2010
Received in revised form 17May 2011Accepted 16August 2011
Available online 7October 2011Keywords:
Sequential Excavation Method (SEM)Monitoring
Finite difference method Weak rock Back analysis Shibli tunnel
a b s t r a c t
Design of Sequential Excavation Method (SEM)and its support system in weathered and incompetent rocks is a primary challenge in tunneling.The Shibli tunnels that are being constructed within Zanjan–Tabriz freeway are located 25km away from Tabriz with total length of 4533m (north tunnel:2244m,south tunnel:2289m),14m width,and 11m height.Three collapses that occurred at initial 800m length of southern tunnel necessitated modi?cation of either or both of the support system or excavation sequences.In this study,modi?cation of the excavation sequences was merely taken into con-sideration for the high costs required to change the support system.Initially,the method of top heading and benching was proposed based on size of tunnels span and the ratio of Uniaxial Compressive Strength (UCS)to vertical in situ stress.Subsequently the excavation sequences were examined and designed pre-cisely.Application of back analysis technique on three aforementioned collapsed zones led to identi?ca-tion of the most probable rock mass shear strength parameters.Results obtained from this analysis showed that in crown part of collapsed zones the displacement values had laid in an interval between 70and 75mm.Therefore,based on the weakest strength parameters obtained from the back analysis,three different sequences of excavation were proposed and sent to a ?nite difference numerical modeling which followed by an ef?cient SEM design with safety factor of 2that reduced the displacements after excavation of top heading and whole tunnel section in the collapsed zones to less than 45mm and 70mm respectively.Thereafter,the modi?ed SEM design has been applied successfully without occur-rence of further collapses throughout excavation of the remained length of Shibli tunnels.
ó2011Elsevier Ltd.All rights reserved.
1.Introduction
The excavation method and sequencing schemes have a great in?uence on deformation of rocks where a tunnel is constructed using Sequential Excavation Method (SEM).The ultimate selection of excavation and sequencing schemes for a speci?c condition should be typically based on complicated interactions occurring between several factors such as safety,cost and schedule consider-ations (Hoek,2001).The second part of Zanjan–Tabriz freeway connects the city of Tabriz to Bostanabad rural area (Fig.1).The twin tunnels of Shibli are being constructed within this freeway to remove heavy traf?c and decrease driving casualties.Their sec-tions are both horse shoe shaped with 14m width and 11m height.The distance between axes of two adjacent tunnels is about 60m.General geology of the project region is strongly in?uenced by two orogenic phases that have led to heavily crushed rock mass in the area.Three collapses in initial 800m length of southern tun-nel are evidences of weakness in the host rock.In order to prevent further collapses,two different alternatives (strategies)could be taken into consideration;(i)modi?cation of the support system and (ii)modi?cation of the excavation sequences.Of course,the second strategy was suggested promptly due to costly nature of support system improvement.In this paper,three SEM schemes are investigated on the basis of geological conditions and ?ndings obtained from displacement back analysis of the collapsed zones.2.Geological and geotechnical investigation
The studied region in which the tunnels are being constructed is located in the outermost west-northern part of central Iran geolog-ical formation.The Shibli tunnels host rocks are mostly composed of gray to black shale,marl and calcareous shale that are heavily crushed by two orogenic phases.According to the engineering geo-logical data and rating scores inferred from surface and under-ground mapping,the host rocks were divided into three:A,B and C blocks at construction stage (Fig.2).Block A,assigned to the most competent part of the host rock containing calcareous and sandy shale.Block B,which belongs to the fair class of RMR index,con-sists of black to gray shale and crushed https://www.wendangku.net/doc/fe8104835.html,stly,the
0886-7798/$-see front matter ó2011Elsevier Ltd.All rights reserved.doi:10.1016/j.tust.2011.08.003
Corresponding author.
E-mail address:most.sharif@https://www.wendangku.net/doc/fe8104835.html, (M.Sharifzadeh).
crushed black shale and marl constitute the host rocks of block C (Daraei,2010).Block C forms the most incompetent rocks that cause the most complicated situation especially where there is combination of high water in?ows and severely tectonized zones. The rock mass quality was scored using rock mass classi?cation systems such as RMR,Q and GSI.Because it has been argued that application of RMR is not so appropriate for incompetent combina-tions of the ground i.e.RMR<(30–40)(Hoek,2006),GSI was used instead to score the weak parts of tunnels.Detailed information of rock mass rating is demonstrated in Table1.In addition,Table2 illustrates the characteristics of four predominant joint sets
inferred from surface mapping and subsurface investigation.Prop-erties of intact rock given in Table3were determined by laboratory tests instead of overpriced and time consuming in situ tests.Cohe-sive strength,friction angle and deformation modulus of the intact
Fig.1.(a)Location of Shibli twin tunnels in Iran map and(b)the picture of Shibli twin tunnels site.
Fig.2.(a)Longitudinal section of Shibli tunnel and(b)geological map of Shibli tunnel.
Table1
Geological blocks scored by engineering classi?cation systems along Shibli tunnel
route.
Rating Block
A B C
RMR49–5243–4638–42
Q 1.2–1.30.75–0.80.6–0.65
GSI44–4738–4133–37
rock were estimated based on the empirical equations of RMR and GSI(suggested by Sera?m and Pereira(1983)and Bieniawski (1989))and then recalculated by RocLab software which has been coded based on Hoek–Brown criterion(Rocscience Inc.,2002). Therefore,tunnels were designed based on a range of values of rock mass properties instead of just a unique value(Table4).
3.Shibli tunnels SEM design and displacement monitoring
Despite preliminary site investigations to characterize rock mass quality,it is not often possible to obtain a complete geome-chanical characterization of the ground along the tunnel route. Therefore,it is essential to monitor the ground deformation during tunneling not only to ensure the safety of construction but also to provide important information for the back analysis.Monitoring of inward tunnel deformation is believed to be a principal means for safe and high quality design of support system and excavation method(Kavvadas,2003).
Prior to Shibli tunnel instabilities,southern and northern tun-nels were being constructed according to a preliminary SEM design with top heading and benching in eight stages as shown in Fig.3. The?gure shows that top heading part was being excavated in two successive stages.Once the?rst stage was?nished,a platform would remain that should be removed in the second stage.The preliminary SEM design was modeled in the?rst collapsed section (in chainage27+340as shown in Fig.4)to determine effective loads on support system.The temporary support system consists of steel rib,shotcrete and rock bolt.The steel rib(IPE180@0.5) embedded in25cm shotcrete were modeled together using Beam element and rock bolt was simulated as Cable element.Numerical modeling results showed that southern tunnel had reached and even exceeded the critical safety factor after both stages of top heading excavations were completed.Acting forces on support sys-tem at southern tunnel prior to instabilities are shown in Table5. Back analysis of monitored deformation in southern tunnel was performed when three collapses veri?ed its instability.Therefore, convergence pins and extensometers were installed in32stations of5–30m interval range.The displacements recorded by the mon-itoring instruments veri?ed that the most unstable station was in chainage27+340of the southern tunnel where eventually the third collapse occurred.In order to use the critical displacements, data recorded in this station was used for modi?cation of SEM design.According to the monitoring data in this station,relative displacements were recorded prior to the third collapse to be 71mm for distances between left wall to right wall(L–R),34mm for crown to left wall(C–L)and36mm for crown to right wall (C–R)(Fig.5).
4.Back analysis of critical sections in southern tunnel
Nowadays,back analysis techniques are frequently used in geotechnical engineering problems as a practical tool to determine unknown parameters of rock mass,geometric systems and preli-minary boundary conditions with the aid of displacement,stress and strain monitoring during excavation or construction of a struc-ture.Displacement-based back analysis techniques have spawned a number of challenging topics since1970s in which enormous stud-ies have resulted in several models of displacement based back anal-ysis(see e.g.Sakurai and Takeuchi,1983;Gioda and Locatelli,1999; Swoboda et al.,1999;Feng et al.,2004;Zhang et al.,2006;Ghorbani and Sharifzadeh,2009).Basically,back analysis solutions can be divided into two inverse and direct categories.In the inverse approach,mathematical formulation of the normal analysis is exactly inversed.In this approach,the number of measured data should be more than the number of unknown data in order to use optimization techniques for regressive calculation of unknowns. The main advantage of inverse approach is its lack of need to repeti-tion that appropriately decreases the time needed for calculations. But the chief disadvantage of this category is in its failure to?nd a stable numerical solution for geotechnical problems which typically have measured values with too wide range of data(Sakurai et al., 2003).Generally,there are three algorithms for direct approach of back analysis.These algorithms are:single variable techniques,mul-tiple variable techniques and periodic single variable techniques (Ghorbani and Sharifzadeh,2009;Jeon and Yang,2004).In order to carry out successfully back analysis calculation,it is necessary to choose:(i)a mathematical model that is able to determine the stress and strain around the tunnel;(ii)an ef?cient algorithm that reduces the error between the calculation results and the observed in situ measurements(Oreste,2005).
In Shibli tunnel,the direct approach of displacement-based back analysis was used to grasp an optimized de?nition of rock mass parameters.The applied method is based on optimization of mechanical properties of rock mass by trial and error.The error function that is de?ned by Eq.(1)was utilized to minimize the dif-ference between measured and calculated displacements through numerical modeling.
Table2
Joint set characterization along the route of Shibli tunnel.
Joint set Dip/dip direction Persistence(m)Aperture(mm)Roughness In?lling(gouge)Weathering
I65/3001–30.1–1.0Smooth Soft?lling<5mm Moderately weathered II68/0673–101–5Smooth Soft?lling<5mm Moderately weathered III14/0323–100.1–1.0Smooth Soft?lling<5mm Moderately weathered IV67/2701–31–5Slickensided Soft?lling<5mm Highly weathered
Table3
Intact rock characteristics and?eld properties.
Block Rating
UCS(MPa)Max.overburden(m)Poisson’s ratio Density(kg/m3)Vertical stress(MPa)USC/sv
A45–481150.222350 2.717.22 B40–451790.252320 4.1510.36 C35–401730.272200 3.89.86
Table4
Geotechnical properties of rock mass along the route of Shibli tunnel.
Block Rating
Cohesion(kPa)Friction angle(°)Deformation modulus(MPa)
A328362380
B357342049
C340331947
12M.Sharifzadeh et al./Tunnelling and Underground Space Technology28(2012)10–17
e ep T????????????????????????????????????????????????
1n X n i ?1u m i ep Tàu i
u i
2
s e1T
In this equation n is the number of measurement points and (i =1,2,...,n )and eu i m Tare the measured and calculated displacements respectively which are calculated for corresponding points through numerical analysis.The value of (p )depends on summed up unknown parameters of the model in P vector.As the equation
shows,this study employs a normalized error function which helps to decrease the effect of measurement errors such as installation,reading and recording errors and therefore precludes misleading information.
In order to perform back analysis,deformation modulus and shear strength parameters (c and u ),the most important parameters of the collapsed area at Shibli tunnel,were considered to employ in the periodic single variable method.In this method,two of the three parameters were assumed as a constant value and other parameter
Table 5
Preliminary excavation pattern and related measurements of displacement,acting forces,and safety factor.Excavation sequences of heading Crown displacement (mm)Right wall displacement (mm)Left wall displacement (mm)N (kN)M (kN m)V (kN)SF I 673467429722.4415.4 1.87II
76
38
39
4528
98.2
27.3
$1
N:Axial force,M:Bending moment,V:Shear force,SF:Safety factor.
M.Sharifzadeh et al./Tunnelling and Underground Space Technology 28(2012)10–1713
was changed in an acceptable range in the model.At the end of each
calculation,the difference between determined displacements and observed displacements was computed by the de?ned error func-tion in Eq.(1).This procedure was repeated for the every possible combination of the parameters and ?nally,that set of parameters that resulted in minimum error was selected as the representative parameters of the rock mass.
After implementation of back analysis method and determina-tion of the most probable strength parameters of the rock mass (Table 6),the new displacement values that resulted from back
analysis calculations,are shown in Table 7to be compared with the measured values.Fig.6demonstrates the numerical modeling of Shibli tunnel and balanced displacements on roof,right wall and left wall at chainage 27+340.
5.Determination of excavation method and sequences
Generally,a simple rule does not exist to facilitate decision mak-ing about optimal selection of excavation method.This decision is
Table 6
Estimated rock mass characteristics from displacement based back analysis.Chainage of station monitoring
Cohesion (kPa)Deformation modulus (GPa)Friction angle (°)Back analysis
Con?ne design Back analysis Con?ne design Back analysis Con?ne design 27+340
204±0.5
202–205
1.36±0.007
1.3–1.42
24±0.5
23–26
Table 7
Measured and calculated displacements at chainage 27+340.Chainage of monitoring station
Calculated values (mm)Measured values (mm)L–R
C–L C–R L–R C–L C–R 27+340(south tunnel)
75
37
39
71
34
36
-3.750-3.700-3.650-3.600-3.500
-3.550(a)
-02
)14M.Sharifzadeh et al./Tunnelling and Underground Space Technology 28(2012)10–17
mainly in?uenced by engineering experiences rather than theoret-ical calculations(Hoek,2001).However,some in?uencing factors on selection of excavation method can be mentioned as rock mass properties including intact rock and joint(discontinuity)character-istics,shape and size of tunnel section,underground hydrology, in situ and induced stresses,regional geology,structural geology and weak zone characteristics(Yu and Chern,2007).Yu and Chern (2007),have also proposed a diagram that can be used as a basis for selection of excavation method(Fig.7).As the diagram illustrated in Fig.7shows,the excavation method can be determined accord-ing to the given span size and ratio of Uniaxial Compressive Strength(UCS)to vertical in situ stress.For Shibli tunnel,after plot-ting the location of blocks A,B and C on the proposed diagram (Fig.7),the top heading and benching method proved to be the most suitable excavation method for all blocks,and therefore the preliminary excavation method remained unchanged.Therefore, detailed sequences of excavation should have been evaluated at the next stage.
Through application of back analysis technique on three col-lapsed zones the most probable rock mass strength parameters (Table6)at the instances of collapses occurrence were identi?ed. Results obtained from the back analysis showed that in the crown part of the collapsed zones the displacement values lie between70 and75mm.Taking into account the existing facilities and resources on the project site such as excavation machinery,steel frames,rolling system and also power and type of shotcreting equipment(dry or wet),three different SEM designs according to Fig.8were proposed.Height of top heading is mainly controlled by two factors namely;boom height of excavation machinery and stability of tunnel.The optimal top heading height(which sat-is?es both the least possibility of instability and most ef?ciency of machinery)was determined to be5.30m up to5.70m based on the numerical modeling calculations and machinery examination. In addition,multi face excavation method(Fig.8b)with manual excavation was proposed to tackle probable confrontation of extre-mely incompetent rock mass during tunneling advance.The FDM simulation models of three different SEM schemes(Fig.8)were run in FLAC2D environment based on the most critical geotechnical data obtained from displacement based back analysis within a 40?40m net,characterized by100?100elements,50cm zone length and perfect elastic–plastic Mohr–Coulomb constitutive model(Itasca Inc.,2002).It had been determined that displace-ments should be less than45mm and70mm after excavation of top heading and whole tunnel section respectively.In addition, bearing in mind that Shibli tunnels were being constructed in weak rocks,the factor of safety had to be greater than2to compensate the effects of underground hydrology and unexpected condition
Table8
Analyzed measurements for comparing performances of three proposed excavation sequences shown in Fig.8.
Excavation method Heading height
(m)
Sequences Roof displacement
(mm)
Right wall displacement
(mm)
Left wall displacement
(mm)
N
(kN)
M
(kN m)
V
(kN)
SF
A 5.30I393834381520.42 5.87 2.11
II414040346332.129.13 2.24
III434041378234.159.87 2.06
IV464543389336.29.96 1.9
V504746392437.0110.2 1.9
VI585152422140.510.89 1.83
VII685758428341.611.03 1.81
B–I46910182118.2333.4 4.39
II907022149494.5152.4 2.9
III>110>80>80506915854.5<1
C 5.70I703634391421.65 6.98 2.04
II743440406233.218.9 1.93 N:Axial force,M:Bending moment,V:Shear force,SF:Safety factor.
M.Sharifzadeh et al./Tunnelling and Underground Space Technology28(2012)10–1715
of excavation.Numerical modeling of three SEM designs showed that the schemes B and C could not ful?ll the calculated critical dis-placement and safety factor.On the other hand,in order to keep on operating with the existing excavation machinery,and not to impose extra costs for acquisition of new machinery due to change in excavation method,it was suggested to remove the platform and excavate the top heading in only one stage(scheme A).Numerical modeling and analysis of scheme A showed that the acting forces on the support system would decrease considerably as compared with the applied scheme prior to the collapses.Detailed data of dis-placement,acting forces on support systems and resulting safety factor are presented individually in Table8for three proposed schemes.Since the calculated displacement of crown part after excavation of top heading was less than the acceptable value and safety factor reached an amount more than threshold of2,the scheme A was accepted as a modi?cation of previous SEM design. Fig.9shows the SEM Scheme A,was simulated in FLAC2D.It should be remembered that in numerical modeling of all three dif-ferent schemes,the support system had remained constant and the modeled support system was considered to be similar to the sup-port system designed prior to the collapses.
6.Discussion
After taking on and executing the modi?ed SEM design,moni-toring of the displacements demonstrated its consistency with the weak host rock and other conditions.Moreover,actual dis-placement amounts in collapsed zones(speci?cally at chainage 27+340of southern tunnel)closely followed the predicted amounts calculated via the analysis.Fig.10shows the trend of dis-placement variations both over time(Fig.10a)and distance from face(Fig.10b)at chainage27+340which had been continuously measured until excavation of the southern tunnel?nished.As shown in Fig.10,displacements on walls and roof increased
when Fig.9.Numerical modeling of excavation pattern A shown in Fig.8by FDM.
bench1and bench2were excavated.This behavior of the ground is the response of tunnel excavation from the monitoring station. Furthermore,ever since the excavation was started again in this chainage with the modi?ed SEM design,some higher?nal dis-placements could be observed in the right wall.This extraordinary behavior can be related to the occurrence of previous conical col-lapse at the right side of monitoring station.
7.Conclusions
Usually,tunneling in weak rocks comes encounter instabilities and environmental problems.Therefore,monitoring ground defor-mations during tunneling can be the main tool for selection of suit-able excavation methods and support systems to ensure safety and high quality of construction.Occurrence of three instabilities in Shibli southern tunnel necessitated the modi?cation of either or both of support system and excavation sequences.Modi?cation of the excavation sequence was taken in hand as change in support system required high expenditures.For excavation method,top heading and benching was proposed based on span size,vertical in situ stress and Uniaxial Compressive Strength of the host rocks. As Fig.3shows,top heading and benching method which this study proved its soundness had been the applied excavation method before instabilities occur and should have been remained unchanged.Instead,excavation sequences had to be designed all over again.Three SEM schemes(Fig.8)were proposed that were different in their excavation sequences and height of top heading in order to take into account machinery size and stability issues simultaneously.Numerical analysis of the proposed SEM schemes demonstrated that proper sequencing is one of the most important factors in design of SEM tunneling.For instance even with a unique excavation method,inappropriate sequencing can lead to occur-rence of instability and failure.In this study,based on displacement monitoring data and experimental observations,modi?cation of excavation sequences by reducing height of top heading part from 6.40–6.70to5.30–5.80implemented and resulted in a successful SEM design that continued over the total3500m length of Shibli tunnels without occurrence of any further instability.References
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交通工程专业英语翻译
公路建设 交通1001 绿学长公路路面结构的地基和分流路就像火车必须在轨道上行驶一样，如果没有桥梁、隧道等特殊结构，那么就需要在原来的土壤或者土堤上修建地基。所以，建造地基也就是道路设施的第一步。 [现场清理] 清理现场前的所有步骤和多数其他施工作业一样。道路开荒在农村地区有时可能只要移除杂草、灌木和其他植物或作物。但是，有时也可能会涉及到大树木、树桩和杂物的处理。我们公认的清理程序还包括处理植物的根茎，因为一旦保留了它们，它们就可能会腐烂并留下空隙，从而导致土质发生沉降。在附近区域进行选择性清除有时也是很必要的。 [开挖] 开挖是一种松动和清除障碍物和标的建设区域岩石与杂物的过程。设备的选取取决于路面材料的质量，并且要考虑到我们的移动作业和设备的处置方法。 开挖的对象通常被描述为'磐石'，'松散岩'或者“普通石块”，其中，“普通石块”意味着没有其他什么特别的分类了。磐石，即坚硬的岩石，几乎总需要钻孔和爆破才能开挖，然后用挖掘机、大卡车或其他大型牵引铲装车辆运输搬运。爆破的碎石块需要用推土机来搬运或转
移一小段距离，实际上这就像是开着一辆巨大的带铲子的拖拉机。“松散岩”，包括风化、腐烂的岩石和夹杂着泥土的较大石块颗粒，我们只需要装载机铲挖而不需要任何之前用的爆破。然而，你可能认为通过进一步松动爆破能够加快工程进度，减少设备损耗并降低成本，但挖掘机铲挖想与爆破施工同时进行却不容易。 近年来，大型松土机被安装在巨大的履带式拖拉机上，被一个或更多的额外的拖拉机推动的方式，已成功地用于破碎松动或断裂岩石。松动的岩石由挖掘机处理，跟“普通”的开挖一样。 “普通开挖”或土方开挖的分级程序受成本影响。如果施工对象被拖运的距离超过200英尺（60米）或下陡坡，应用轨道或轮式推土机运送，这样较为合算。对于较长距离的运送，则使用自动化刮拉胶轮牵引车来运送，并由拖拉机装填以降低成本。有时它更适合用带有电力驱动分离拖片的牵引车来清障。对于限制车长和轴重的地区，应采用后部或底部带铲的装载机和挖掘机，皮带式运输机可能是最划算的道路装载卡车。有时，天气可能会影响到施工进程。例如，胶轮拖拉机车在湿滑的路面施工就比较困难。因此，在下暴雨的时候，用刮拉履带式拖拉机会更便于施工。 运土工业自1925年以来发生了革命性变化，最常用的工具是一个至多1/2码（0.4米），由两到四匹马或骡子拉的牵引刮板。例如，15码（1100米）的装载机需要和125吨的卡车组合使用。32码（2400米）的铲运机破土能力与两个发动机安装在后部刮板用来供应增加牵
土木工程专业英语翻译
a common way to construct steel truss and prestressed concrete cantilever spans is to counterbalance each cantilever arm with another cantilever arm projecting the opposite direction,forming a balanced cantilever. they attach to a solid foundation ,the counterbalancing arms are called anchor arms /thus,in a bridge built on two foundation piers,there are four cantilever arms ,two which span the obstacle,and two anchor arms which extend away from the obstacle,because of the need for more strength at the balanced cantilever's supports ,the bridge superstructure often takes the form of towers above the foundation piers .the commodore barry bridge is an example of this type of cantilever bridge 一种常见的方法构造钢桁架和预应力混凝土悬臂跨度是每一个悬臂抗衡预测相反的方向臂悬臂，形成一个平衡的悬臂。他们重视了坚实的基础，制约武器被称为锚武器/因此，在两个基础上建一座桥桥墩，有四个悬臂式武器，这两者之间跨越的障碍，和两个锚武器哪个延长距离的障碍，因为为更多的在平衡悬臂的支持力量的需要，桥梁上部结构往往表现为塔墩基础之上形成的准将巴里大桥是这种类型的例子悬臂桥 steel truss cantilever support loads by tension of the upper members and compression of the lower ones .commonly ,the structure distributes teh tension via teh anchor arms to the outermost supports ,while the compression is carried to the foundation beneath teh central towers .many truss cantilever bridges use pinned joints and are therefore statically determinate with no members carrying mixed loads 钢桁架悬臂由上层成员和下层的紧张压缩支持负载。通常，结构分布通过锚武器的最外层的支持紧张，而压缩抬到下方的中央塔的基础。桁架悬臂许多桥梁使用固定的关节，是静定，没有携带混合负载的成员，因此 prestressed concrete balanced cantilever bridges are often built using segmental construction .some steel arch bridges are built using pure cantilever spans from each sides,with neither falsework below nor temporary supporting towers and cables above ,these are then joined with a pin,usually after forcing the union point apart ,and when jacks are removed and the bridge decking is added the bridge becomes a truss arch bridge .such unsupported construction is only possible where appropriate rock is available to support the tension in teh upper chord of the span during construction ,usually limiting this method to the spanning of narrow canyons 预应力混凝土平衡悬臂桥梁往往建立使用段施工。一些钢拱桥是使用各方面的纯悬臂跨度既无假工作下面也临时支撑塔和电缆上面，这些都是再加入了一根针，通常在迫使工会点外，当插孔删除，并添加桥梁甲板桥成为桁架拱桥，这种不支持的建设，才可能在适当情况下的岩石可用于支持在施工期间的跨度弦上的张力，通常限制这狭隘的峡谷跨越方法 an arch bridge is a bridge with abutments at each end shaped as a curved arch .arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side .a viaduct may be made from a series of arches ,although other more economical structures are typically used today 在拱桥桥台的桥梁，是一个在一个弧形拱状，每年年底。拱桥通过转移到由部分在两边的桥台水平推
资料：《安全工程专业英语(部分翻译)》
Unit 1 safety management system Accident causation models 事故致因理论 Safety management 安全管理Physical conditions 物质条件Machine guarding 机械保护装置House-keeping 工作场所管理 Top management 高层管理人员Human errors 人因失误 Accident-proneness models 事故倾向模型Munitions factory 军工厂 Causal factors 起因 Risking taking 冒险行为 Corporate culture 企业文化 Loss prevention 损失预防 Process industry 制造工业 Hazard control 危险控制 Intensive study 广泛研究Organizational performance 企业绩效Mutual trust 相互信任Safety officer 安全官员Safety committee 安全委员会Shop-floor 生产区Unionized company 集团公司Seniority 资历、工龄Local culture 当地文化Absenteeism rate 缺勤率Power relations 权力关系 Status review 状态审查 Lower-level management 低层管理者Business performance 组织绩效Most senior executive 高级主管Supervisory level 监督层Safety principle 安全规则 Wall-board 公告栏Implement plan 执行计划 Hazard identification 危险辨识Safety performance 安全性能 One comprehensive definition for an organizational culture has been presented by Schein who has said the organizational culture is “a pattern of basic assumptions –invented, discovered, or developed by a given group as it learns to cope with its problems of external adaptation and internal integration –that has worked well enough to be considered valid and, therefore, to be taught to new members as the correct way to perceive, think, and feel in relation to those problems” 译文：Schein给出了组织文化的广泛定义，他认为组织文化是由若干基本假设组成的一种模式，这些假设是由某个特定团体在处理外部适应问题与内部整合问题的过程中发明、发现或完善的。由于以这种模式工作的有效性得到了认可，因此将它作为一种正确的方法传授给新成员，让他们以此来认识、思考和解决问题[指适应外部与整合内部的过程中的问题]。 The safety culture of an organization is the product of individual and group values, attitudes, perceptions, competencies, and patterns of behavior that determine the commitment t o, and the style and proficiency of , an organization’s health and safety management. 译文：组织的安全文化由以下几项内容组成：个人和群体的价值观、态度、观念、能力和行为方式。这种行为方式决定了个人或团体对组织健康安全管理的责任，以及组织健康安全管理的形式和熟练程度。
交通工程专业英语翻译1
The Evolution of Transport 交通运输业的发展 交通运输的发展一直密切联系在一起的人类发展的整个地球的历史。运输的早期功能是为了满足提供食物供给和搬运建筑材料。但是随着部落甚至最后国家的形成，运输的社会和经济功能越来越复杂。起初有需要调动个人，家族，家庭和动物以保护他们的反对，并逃避自然灾害和部族侵略的危险，寻找最好的地方定居。随着种族部落的形成和地理界线的逐步确定，开发新区域、开采新资源、发展社区间的贸易以及捍卫领地，这些都日益需要交通的发展。当第一个国家应运而生,在建立全国的完整性方面,交通运输扮演着重要角色。 基本的社会需求一般都得到照顾后，当地社区可以越来越多地贡献自己的努力，用来加强与其他国家的人民和他们的经济贸易联系，文化和科技发展。而且交通提供了诸如部落间、国际间乃至于洲际间便利的贸易和文化交流。在向有组织的人类社会的演变过程中，这种组织在今天是通过由各国组成的国际化大家庭表现出来的，交通作为人与货物移动的物理过程，电促进了这种发展，不断地经历着技术与组织方面的改变。这些变化是由多种因素和情况引起的。事实上,今天的运输在它的各种形态和组织仍然高度受变化的社会需求和偏好的回应。 显然,首先也是最重要的标准是运输效率。几个世纪以来，特别是在地方经济起飞阶段，社会需要可靠、快速、低成本的运输。为寻找合适的技术相对不受限制。在人类历史上有可靠的时候，快速运输的需求尤其明显，快速的解决办法，为国家自卫所需的时间。在当地和国际冲突的时期内，人类的聪明才智设计出新的传输技术，可往往被证明是为逃生、有时也是为了胜利，的决定性因素。随后完善和发展，这种新技术使我们能够更好地满足日益增加的运输需求，从而改善双方的经济发展和人类福祉。 为更好的战略机动诱导努力提高海上和陆路运输的需要。这导致了更大，更快的船，更可靠，坚固的地面车辆。最后，详细介绍了汽船，铁路，然后是汽车的例证。研究和运输领域的发展终于成为一个具体的目标和组织目标的承诺。随之而来的是专家的集中，越来越复杂的运输技术的进化,如飞机,和最新的火箭推进器。 日益复杂的运输手段逐渐发展成今天的运输系统，其中包括空中、路面和水上运输。特殊行业的需求，引起了发展出相当有限的应用的运输模式，如管道，电缆和传送带。因为当前社会的需求和喜好，以及经济要求的成本效益，现有的各种运输方式一般都能完成特定功能。 尽管运输的潜力以满足社会的流动性需要而水平不断提高，但很明显，这种效果有其代价。大量的交通技术要求和隐含的能耗高的巨大的资金投入生产和经营。因此，一些运输方式对使用者来说是昂贵的。这引起权益问题，因为需要支付运作成本费用是不是所有的人口群体负担，从而限制其流动性和福利。许多国家的政府选择了运输补贴，但很快就意识到，预算往往对其国家的经济造成严重的扭曲。 各种运输方式污染造成的，逐渐成为另一问题，如同世界大多数国家需要应付不断上升的商品流动和人的旅行量严重的问题。在一些地区具有高浓度的人口和产业，这种对环境的不利影响已达到很高的水平。这种损害是这些影响尚未得到充分开发。 最后，这些问题引起世界能源资源的日益减少，特别是石油，已越来越多地阻碍交通服务和操作。大多数现有的运输方式都是以依赖石油衍生品才能正常运转。随着需求量的增长与不衰减得运输和能源供应的有限，逐步提供运输的成本已经稳步增加。特别是，石油需求和石油供应不均衡造成了严重的通货膨胀问题出现在许多国家。尤其沉重的打击与对外部石油供应，其中也经历了他们的经常帐赤字增长部分或完全依赖国家。 运输部门的增加无法满足有效且公平需求的问题，这是一个所有国家必须应对努力促进经济和社会进步。能源供应的限制，高额的资本和运营成本，往往与外汇组件以及与运输有关的环境污染的很大一部分用于这个严重性的问题。但运输是并将继续是世界发展和人类福利的基本要求。没有任何其他选择，只能寻求替代或修改目前的运输系统，使能源消耗和成本永存相关的技术和业务模式的特点是减少对环境的影响，可以保持在最低水平。显然，交通需求的发展将被控制。翻译：设计目标, 公交优先已被看到在整体城市交通的战略目标,不仅包括改善公共汽车(或电车)操作和 克制,car-borne通勤更是一种增强环境,为居民、工人和游客。方法必须为所有这些也有明显的目标而成本和执行。 典型的设计目标为公交优先的措施包括:
土木工程专业英语原文及翻译
土木工程专业英语原文 及翻译 文档编制序号：[KKIDT-LLE0828-LLETD298-POI08]
08 级土木(1) 班课程考试试卷 考试科目专业英语 考试时间 学生姓名 所在院系土木学院 任课教师 徐州工程学院印制 Stability of Slopes Introduction Translational slips tend to occur where the adjacent stratum is at a relatively shallow depth below the surface of the slope:the failure surface tends to be plane and roughly parallel to the slips usually occur where the adjacent stratum is at greater depth，the failure surface consisting of curved and plane sections． In practice, limiting equilibrium methods are used in the analysis of slope stability. It is considered that failure is on the point of occurring along an assumed or a known failure surface．The shear strength required to maintain a condition of limiting equilibrium is compared with the available shear strength of the soil，giving the average factor of safety along the failure surface．The problem is considered in two dimensions，conditions of plane strain being assumed．It has been shown that a two-dimensional analysis gives a conservative result for a failure on a three-dimensional(dish-shaped) surface． Analysis for the Case of φu =0 This analysis, in terms of total stress，covers the case of a fully saturated clay under undrained conditions, . For the condition immediately after construction．Only moment equilibrium is considered in the analysis．In section, the potential failure surface is assumed to be a circular arc. A trial failure surface(centre O，radius r and length L a where F is the factor of safety with respect to shear strength．Equating moments about O：
交通工程专业英语翻译The_Evolution_of_Transport
交通工程专业英语翻译The_Evolution_of_Transport The Evolution of Transport 交通运输业的发展 The evolution of transport has been closely linked to the development of humankind throughout the earth’s history(交通运输的发展一直与的人类发展的整 个地球的历史密切联系在一起。 Transport’s early function was to meet the basic need of hauling food supplies and building materials(运输的早期功能是为了满足食物供给和搬运建筑材料的 基本 需求。 But with the formation of tribes，then peoples，and finally nations，the societal and economic functions of transport became more and more complex. 但是随着部落的 产生甚至最后国家的形成，运输在社会和经济起到的功能越来越复杂。 At first there was mobility required for individuals，clans，households，and animals to protect them against，and to escape from，the dangers of natural disasters and tribal aggressions，and in the search for the best places to settle(起初有 需要调动个人， 家族，家庭和动物以保护他们来反抗并逃避自然灾害和部族侵略的危险，从而寻
土木工程专业英语课文原文及对照翻译
土木工程专业英语课文原 文及对照翻译 Newly compiled on November 23, 2020
Civil Engineering Civil engineering, the oldest of the engineering specialties, is the planning, design, construction, and management of the built environment. This environment includes all structures built according to scientific principles, from irrigation and drainage systems to rocket-launching facilities. 土木工程学作为最老的工程技术学科，是指规划，设计，施工及对建筑环境的管理。此处的环境包括建筑符合科学规范的所有结构，从灌溉和排水系统到火箭发射设施。 Civil engineers build roads, bridges, tunnels, dams, harbors, power plants, water and sewage systems, hospitals, schools, mass transit, and other public facilities essential to modern society and large population concentrations. They also build privately owned facilities such as airports, railroads, pipelines, skyscrapers, and other large structures designed for industrial, commercial, or residential use. In addition, civil engineers plan, design, and build complete cities and towns, and more recently have been planning and designing space platforms to house self-contained communities. 土木工程师建造道路，桥梁，管道，大坝，海港，发电厂，给排水系统，医院，学校，公共交通和其他现代社会和大量人口集中地区的基础公共设施。他们也建造私有设施，比如飞机场，铁路，管线，摩天大楼，以及其他设计用作工业，商业和住宅途径的大型结构。此外，土木工程师还规划设计及建造完整的城市和乡镇，并且最近一直在规划设计容纳设施齐全的社区的空间平台。 The word civil derives from the Latin for citizen. In 1782, Englishman John Smeaton used the term to differentiate his nonmilitary engineering work from that of the military engineers who predominated at the time. Since then, the term civil engineering has often been used to refer to engineers who build public facilities, although the field is much broader 土木一词来源于拉丁文词“公民”。在1782年，英国人John Smeaton为了把他的非军事工程工作区别于当时占优势地位的军事工程师的工作而采用的名词。自从那时起，土木工程学被用于提及从事公共设施建设的工程师，尽管其包含的领域更为广阔。 Scope. Because it is so broad, civil engineering is subdivided into a number of technical specialties. Depending on the type of project, the skills of many kinds of civil engineer specialists may be needed. When a project begins, the site is surveyed and mapped by civil engineers who locate utility placement—water, sewer, and power lines. Geotechnical specialists perform soil experiments to determine if the earth can bear the weight of the project. Environmental specialists study the project’s impact on the local area: the potential for air and
土木工程专业英语翻译(武汉理工大学出版社段兵廷主编)完整版
第一课土木工程学 土木工程学作为最老的工程技术学科，是指规划，设计，施工及对建筑环境的管理。此处的环境包括建筑符合科学规范的所有结构，从灌溉和排水系统到火箭发射设施。 土木工程师建造道路，桥梁，管道，大坝，海港，发电厂，给排水系统，医院，学校，公共交通和其他现代社会和大量人口集中地区的基础公共设施。他们也建造私有设施，比如飞机场，铁路，管线，摩天大楼，以及其他设计用作工业，商业和住宅途径的大型结构。此外，土木工程师还规划设计及建造完整的城市和乡镇，并且最近一直在规划设计容纳设施齐全的社区的空间平台。 土木一词来源于拉丁文词“公民”。在1782年，英国人John Smeaton为了把他的非军事工程工作区别于当时占优势地位的军事工程师的工作而采用的名词。自从那时起，土木工程学被用于提及从事公共设施建设的工程师，尽管其包含的领域更为广阔。 领域。因为包含范围太广，土木工程学又被细分为大量的技术专业。不同类型的工程需要多种不同土木工程专业技术。一个项目开始的时候，土木工程师要对场地进行测绘，定位有用的布置，如地下水水位，下水道，和电力线。岩土工程专家则进行土力学试验以确定土壤能否承受工程荷载。环境工程专家研究工程对当地的影响，包括对空气和地下水的可能污染，对当地动植物生活的影响，以及如何让工程设计满足政府针对环境保护的需要。交通工程专家确定必需的不同种类设施以减轻由整个工程造成的对当地公路和其他交通网络的负担。同时，结构工程专家利用初步数据对工程作详细规划，设计和说明。从项目开始到结束，对这些土木工程专家的工作进行监督和调配的则是施工管理专家。根据其他专家所提供的信息，施工管理专家计算材料和人工的数量和花费，所有工作的进度表，订购工作所需要的材料和设备，雇佣承包商和分包商，还要做些额外的监督工作以确保工程能按时按质完成。 贯穿任何给定项目，土木工程师都需要大量使用计算机。计算机用于设计工程中使用的多数元件（即计算机辅助设计，或者CAD）并对其进行管理。计算机成为了现代土木工程师的必备品，因为它使得工程师能有效地掌控所需的大量数据从而确定建造一项工程的最佳方法。 结构工程学。在这一专业领域，土木工程师规划设计各种类型的结构，包括桥梁，大坝，发电厂，设备支撑，海面上的特殊结构，美国太空计划，发射塔，庞大的天文和无线电望远镜，以及许多其他种类的项目。结构工程师应用计算机确定一个结构必须承受的力：自重，风荷载和飓风荷载，建筑材料温度变化引起的胀缩，以及地震荷载。他
资料《安全工程专业英语部分翻译》
Ｕnｉt 1safeｔy manaｇement ｓyｓtem Ａcciｄent ｃａｕｓatｉon ｍoｄels ?事故致因理论 Ｓafety managemeｎt 安全管理 Phｙsｉｃａｌｃonditions ?物质条件 Mａcｈinｅguａrdinｇ?机械保护装置 Ｈouse—keepiｎｇ工作场所管理 Ｔｏｐmanagement 高层管理人员Ｈuman ｅｒrorｓ人因失误 Aｃcidenｔ-pｒonenｅss ｍｏdels 事故倾向模型 Muniｔｉoｎs faｃtｏrｙ?军工厂Causal fａctors?起因 Rｉskinｇtakiｎg?冒险行为 Coｒpｏraｔｅｃｕlture 企业文化 Ｌosｓprevention 损失预防 Prｏcess indusｔry?制造工业 Haｚard coｎtrol 危险控制 Intensｉve ｓtudｙ广泛研究 Orgａniｚationaｌperｆｏrmａnce 企业绩效 Mｕtual trust 相互信任Sａfｅｔｙoffiｃer?安全官员 Ｓafeｔy commｉttee 安全委员会 Ｓhop-fｌｏｏr?生产区Unioniｚed company 集团公司 Seｎioｒitｙ?资历、工龄Local ｃuｌturｅ当地文化Absenｔeｅiｓm rａｔｅ?缺勤率Power reｌａtioｎｓ?权力关系 Stａtus review 状态审查Lower—ｌevel managemenｔ低层管理者 Business pｅrformance?组织绩效 Ｍｏst seniｏｒexｅcｕtiｖe 高级主管Superｖisory levｅl监督层 Ｓａfety pｒincipｌe?安全规则 Waｌl—boarｄ?公告栏 Imｐlement plan?执行计划 Ｈazarｄidenｔificａtion 危险辨识 Ｓａfeｔy pｅrfｏｒmance 安全性能 One comｐrｅｈensｉve definition fｏr an orgaｎｉzatｉonａl cｕｌture ｈas been presentｅdｂｙＳｃhein wｈo has said thｅorganｉｚatiｏnal culturｅiｓ“a patteｒn ｏf baｓic asｓumptionｓ–inveｎｔed, dｉｓcovere ｄ，or deveｌoｐｅｄby ａgiven gｒｏup as iｔlearns to cope with iｔs pｒｏbｌｅms of exｔｅrnal adaｐｔａｔiｏn and inｔernal integratioｎ– that h ａs ｗorked weｌl enouｇｈto be consiｄereｄｖａliｄand,tｈｅrｅｆore, to beｔａught to new memｂeｒｓas the corrｅｃt way to peｒcｅive, thin ｋ,and feel in rｅlatiｏn to ｔhosｅｐrobｌemｓ” 译文:Scheｉｎ给出了组织文化的广泛定义，他认为组织文化是由若干基本假设组成的一种模式,这些假设是由某个特定团体在处理外部适应问题与内部整合问题的过程中发明、发现或完善的.由于以这种模式工作的有效性得到了认可,因此将它作为一种正确的方法传授给新成员,让他们以此来认识、思考和解决问题[指适应外部与整合内部的过程中的问题]。 The ｓafety cｕltｕｒe oｆan organization isｔhe proｄuct ｏf inｄividuａl aｎd ｇroｕp valueｓ,attitudes, ｐerceｐｔioｎs, ｃompｅtencｉｅs, aｎd pa ｔternsｏfｂｅhａviｏr that determine tｈe commitmｅｎt to, aｎd tｈe style and proficieｎcy oｆ,an organｉｚatioｎ’ｓｈｅａlｔｈanｄｓafeｔy manａgement.
土木工程英文翻译
外文文献及译文 文献、资料题目：PROTECTION AGAINST HAZARDS 院（部）：建筑工程学院 专业：土木工程 班级：土木081 姓名：孙继佳 学号：200811003192 指导教师：樊江 翻译日期：2012.5.4
3.1 PROTECTION AGAINST WA TER Whether thrust against and into a building by a flood, driven into the interior by a heavy rain, leaking from plumbing, storm surge, or seeping through the exterior enclosure, water can cause costly damage to a building. Consequently, designers should protect buildings and their contents against water damage. Protective measures may be divided into two classes: floodproofing and waterproofing.Floodproofing provides protection against flowing surface water, commonly caused by a river overflowing its banks. Waterproofing provides protection against penetration through the exterior enclosure of buildings of groundwater, rainwater,and melting snow. Buildings adjacent to large water bodies may also require protection from undermining due to erosion and impact from storm driven waves. 3.4.1Floodproo?ng A ?ood occurs when a river rises above an elevation,called ?ood stage,and is not Prevented by enclosures from causing damage beyond its banks.Buildings con- Structed in a ?ood plain,an area that can be inundated by a ?ood,should be Protected against a ?ood with a mean recurrence interval of 100 years.Maps Showing ?ood-hazard areas in the United States can be obtained from the Federal InsuranceAdministrator,DepartmentofHousingandUrbanDevelopment,who Administers the National Flood Insurance Program.Minimum criteria for?ood- proo?ng are given in National Flood Insurance Rules and Regulations(Federal Register, vol.41,no.207,Oct.26,1976). Major objectives of ?oodproo?ng are to protect fully building and contents from Damage from a l00-year ?ood,reduce losses from more devastating ?oods,and Lower ?ood insurance premiums.Floodproo?ng,however,would be unnecessary if Buildings were not constructed in ?ood prone areas.Building in ?ood prone areas Should be avoided unless the risk to life is acceptable and construction there can Be economically and socially justi?ed. Some sites in flood prone areas possess some ground high enough to avoid flood damage. If such sites must be used, buildings should be clustered on the high areas. Where such areas are not available, it may be feasible to build up an earth fill, with embankments protected against erosion by water, to raise structures above flood levels. Preferably, such structures should not have basements, because they would require costly protection against water pressure. An alternative to elevating a building on fill is raising it on stilts (columns in an unenclosed space). In that case, utilities and other services should be protected against damage from flood flows. The space at ground level between the stilts may be used for parking automobiles, if the risk of water damage to them is acceptable or if they will be removed before flood waters reach the site. Buildings that cannot be elevated above flood stage should be furnished with an impervious exterior. Windows should be above flood stage, and doors should seal tightly against their frames. Doors and other openings may also be protected with a flood shield, such as a wall. Openings in the wall for access to the building may be protected with a movable flood shield, which for normal conditions can be stored
安全工程专业英语Unit1-9翻译
安全工程专业英语 Unit1 1. Because of the very rapid changes in these jobs and professions, it is hard for students to learn about future job opportunities. It is even more difficult to know about the type of preparation that is needed for a particular profession-or the qualities and traits that might help individuals succeed in it. 由于这些工作和职业的飞速变更，其变化之快使得学生们很难了解未来有什么样的工作机会，更不知道为未来的具体职业生涯做出怎样的准备，也就是说学生们很难知道掌握何种知识、具备何种能力才能成功适应未来的社会。 2. The purpose of this article is to provide in depth information about the safety profession that should help students considering a career in this challenging and rewarding field. 这篇文章将提供较为深入的安全专业方面的具体信息，它应该能够为安全专业的学生们在这个充满挑战也蕴含着发展机遇的职业中获得良好的发展而提供帮助。 3. While these efforts became more sophisticated and widespread during the twentieth century, real progress on a wide front did not occur in the U.S. until after Word War Ⅱ. 尽管这些专业手段在20世纪已经发展的较为成熟，也具有一定的广泛适应性，但在美国，这些都是第二次世界大战以后才取得的突破性进展。 4. This legislation was important because it stressed the control of workplace hazards. This, in turn, defined a clear area of practice for the previously loosely organized safety profession. Other legislation passed during the next twenty years has increased the scope of safety practice into areas of environmental protection, product safety, hazardous materials management and designing safety into vehicles, highways, process plants and buildings. 这部法律很重要，因为它强调工作场所的危险控制，同时这部法律也为以前不成体系的安全业务划定了工作范围。此后20年中通过的一