这是要写毕业论文了吗？老师会给的，自己翻译一下就好了。
土木工程常用英文期刊集粹土木工程常用英文期刊集粹Chaos, Solit***** and Fractals Computer Methods in Applied Mechanics and Engineering Computers and Structures Engineering Structures European Journal of Mechanics - A/Solids Finite Elements in Analysis and Design International Journal of Non-Linear Mechanics International Journal of Solids and Structures Journal of Wind Engineering and Industrial Aerodynamics Probabilistic Engineering Mechanics Reliability Engineering and System Safety Soil Dynamics and Earthquake Engineering Structural Safety Thin-Walled Structures ASCE Journal of Engineering Mechanics Journal of Structural Engineering Academic Press Journal of Sound and Vibration IOS Press Shock and Vibration ASME Journal of Applied Mechanics Applied Mechanics Review John Wiley&S*****, L International Journal for Numerical Methods in Engineering, Earthquake Engineering and Structural Dynamics Spring-Verlag Archive of Applied Mechanics Computational Mechanics Structural Optimization Kluwer Academic Publishers Nonlinear Dynamics AIAA AIAA Journal ACI Structural Journal Canadian Journal of Civil Engineering Civil Engineering and Environmental Systems Structural engineering and Mechanics 所列期刊基本上都是属于SCI检索范围 属土木类的顶级刊物,搞科研不可不看哦田间阡陌2010-05-14 10:44我是搞桥梁抗震的：1 Bulletin of Earthquake Engineering(Springer)《地震工程通报》刊载地震工程研究方面的原始论文及跨学科文章。2 Bulletin of the Seismological Society of America (GSW)《美国地震学会通报》美国地震学会刊物，刊载地震学、地震工程及相关领域研究论文。在地震学核心刊物中排名第18。2004年影响因子IF：8123 Canadian Geotechnical Journal (Canada NRC) 《加拿大土工杂志》是世界上地球勘察领域的三大学术期刊之一。其内容涉及地层基础，挖掘，土壤资源，水坝，筑堤，斜坡，地下水利的新发展，岩石工程，地球化学，废物管理和输送，土壤冻结，结冰，下雪，海岸土壤以及地缘战略学。4 Clay Minerals (GSW) 《粘土矿物》刊载粘土与粘土矿物分析、物理与化学性质、地质与土壤研究以及粘土矿的利用等方面的研究论文。在矿物学核心刊物中排名第12位，2005年影响因子IF：1845 Computational Geosciences (Springer) 《计算地球科学》 刊载以数学模拟、仿真模拟、数据分析、形象化、反演等手段研究地球科学的高质量论文。6 Disasters (Wiley Black) 《灾害》刊载研究各种自然灾害（地震、洪水、热带风暴等）的预防政策制定及其实施等方面学术论文、实地研究文章、会议报告和书评。7 Earthquake Engineering and Structural Dynamics (Wiley) 《地震工程与结构动力学》 国际地震工程学会会刊。发表地震工程及其他动力负荷形式的研究文章，涉及地震频度、地面运动、土壤扩展与破坏、动力学分析方法、结构实验性能、震情分析等，兼载书评与会议消息。8 Natural Hazards (Springer) 《自然灾害》刊载自然灾害和技术性灾害的物理问题、灾难事件预测统计学、风险评价、灾害先兆的性质等方面的研究论文、评论、实例分析等，兼及相关的社会与政治问题及学术界动态。9 Natural Hazards Observer (NH R & A I Center) 《自然灾害观察者》报道地震、洪水等自然灾害的研究、计划与活动。10 Nonlinear Processes in G (AGU) 《地球物理学中的非线性过程》主要刊登以下两方面真正有创造性贡献的文章：动力学系统理论和应用非线性方法研究地球物理学基础问题。11Quarterly Journal of Engineering Geology & Hydrogeology (GSW) 《工程地质学与水文地质学季刊》伦敦地质学会（GSL）刊物，刊载地质学在土木工程、采矿及水资源开发等领域的应用论文与评论。2004年影响因子IF：8912Rock Mechanics and Rock Engineering (Springer) 《岩石力学与岩石工程》刊载工程地质学、岩石工程、土壤力学、岩石力学等领域的实验、理论和应用方面的研究论文。我看了一下楼主列出的期刊，里面没有的我就补充了一下，这里给出的是我常用到的，主要是地震学、灾害学、地震工程学方面，大家可以看一看。如果有重复的，可能是我没有看仔细，还请见谅。
知道几个，但英文不会写。
土木工程的话肯定是EI、SCI了，下面是一些简介，希望对你有帮助，求加分SCI：是一部国际性的检索刊物，包括有：自然科学、生物、医学、农业、技术和行为科学等，主要侧重基础科学。所选用的刊物来源于94个类、40多个国家、50多种文字，这些国家主要有美国、英国、荷兰、德国、俄罗斯、法国、日本、加拿大等，也收录一定数量的中国刊物。 EI：《工程索引》（The Engineering Index，简称EI）创刊于1884年，是美国工程信息公司（Engineering information I）出版的著名工程技术类综合性检索工具。EI每月出版1期，文摘3万至4万条；每期附有主题索引与作者索引；每年还另外出版年卷本和年度索引，年度索引还增加了作者单位索引。收录文献几乎涉及工程技术各个领域。例如：动力、电工、电子、自动控制、矿冶、金属工艺、机械制造、土建、水利等。它具有综合性强、资料来源广、地理覆盖面广、报道量大、报道质量高、权威性强等特点。
土壤在压力和剪应力下出现的不同变化说明，我们要把压力和形变分成两部分：一部分描述压力，另一部分描述剪应力。本章将对此进行讨论，我们先不考虑膨胀性。1 应力与压力
有一篇施工监控的论文，你查收一下吧，希望对你有用！
刚好我也在做毕业设计 把我的给你用吧！ Traditional Construction ProceduresAs mentioned before, construction under the traditional construction procedure is performed by While they would like to satisfy the owner and the building designers, contractors have the main objective of making a Hence, their initial task is to prepare a bid price based on an accurate estimate of construction This requires development of a concept for performance of the work and a construction time After a contract has been awarded, contractors must furnish and pay for all materials, equipment, power, labor, and supervision required for The owner compensates the contractors for construction costs and A general contractor assumes overall responsibility for construction of a The contractor engages subcontractors who take responsibility for the work of the various trades required for For example, a plumbing contractor installs the plumbing, an electrical contractor installs the electrical system, and an elevator contractor installs Their contracts are with the general contractor, and they are paid by the general Sometimes, in addition to a general contractor, the owner contracts separately with specialty contractors, such as electrical and mechanical contractors, who perform a substantial amount of the work require for a Such contractors are called prime Their work is scheduled and coordinated by the general contractor, but they are paid directly by the Sometimes also, the owner may use the design-build method and award a contract to an organization for both the design and construction of a Such organizations are called design-build One variation of this type of contract is employed by developers of groups of one-family homes or low-rise apartment The homebuilder designs and constructs the dwellings, but the design is substantially completed before owners purchase the Administration of the construction procedure often is Consequently, some owners seek assistance from an expert, called a professional construction manager, with extensive construction experience, who receives a The construction manager negotiates with general contractors and helps select one to construct the Managers usually also supervise selection of During construction, they help control costs, expedite equipment and material deliveries, and keep the work on In some cases, instead, the owner may prefer o engage a construction program manager, to assist in administrating both design and Construction contractors employ labor that may or may not be Unionized craftspeople are members of unions that are organized by construction trades, such as carpenter, plumber, and electrician unions, Union members will perform only the work assigned to their During construction, all work should be For this purpose, the owner, often through the architect and consultants, engages The field inspectors may be placed under the control of an owner’s representative, who may be titled clerk of the works, architect’s superintendent, engineer’s superintendent, or resident The inspectors have the responsibility of ensuring that construction meets the requirements of the contract documents and is performed under safe Such inspections may be made at frequent In addition, inspections also are made by representatives of one or more governmental They have the responsibility of ensuring that construction meets legal requirements and have little or no concern with detailed conformance with the contract Such legal inspections are made periodically or at the end of certain stages of One agency that will make frequent inspections is the local or state building department, whichever has The purpose of these inspections is to ensure conformance with the local or state building Following is a description of the basic traditional construction procedure for a multistory After the award of a construction contract to a general contractor, the owner may ask the contractor to start a portion of the work before signing of the contract by giving the contractor a letter of intent or after signing of the contract by issuing a written notice to The contractor then obtains construction permits, as required, form governmental agencies, such as the local building, water, sewer, and highway The general contractor plans and schedules construction operations in detail and mobilizes equipment and personnel for the Subcontractors are notified of the contract award and issued letters of intent or awarded subcontracts, then are given, at appropriate times, notices to Before construction starts, the general contractor orders a survey to be made of adjacent structures and terrain, both for the record and to become knowledgeable of local A survey is then made to lay out Field offices for the contractor are erected on or near the If desirable for safety reasons to protect passersby, the required to be removed from the site are demolished and the debris is carted Next, the site is prepared to receive the This work may involve grading the top surface to bring it to the proper elevations, excavating to required depths for basement and foundations, and shifting of utility For deep excavations, earth sides are braced and the bottom is Major construction starts with the placement of foundations, on which the building This is followed by the erection of load-bearing walls and structural Depending on the height of the building, ladders, stairs, or elevators may be installed to enable construction personnel to travel from floor to floor eventually to the Also, hoists may be installed to lift materials to upper If needed, temporary flooring may be placed for use of As the building rises, pipes, ducts, and electric conduit and wiring are Then, permanent floors, exterior walls, and windows are At the appropriate time, permanent elevators are If required, fireproofing is placed for steel Next, fixed partitions are built and the roof and its covering are put is place,Finishing operations There include installation of the following: ceilings; tile; wallboard; wall paneling; plumbing fixtures; heating furnaces; air-conditioning equipment; heating and cooling devices for rooms; escalators; floor coverings; window glass; movable partitions; doors; finishing hardware; electrical equipment and apparatus, including lighting fixtures, switches, transformers, and controls; and other items called for in the drawings and Field offices, fences, bridges, and other temporary construction must be removed from the Utilities, such as gas, electricity, and water, are hooked up to the The sit is landscaped and Finally, the building interior is painted and The owner’s representatives then give the building a final If they find that the structure conforms with the contract documents, the owner accepts the project and gives the general contractor final payment on issuance by the building department of a certificate of occupancy, which indicates that the completed building meets building-code 传统的施工程序众所周知，在传统的施工程序中进行施工的承包商。尽管他们想满足业主和建筑设计师的要求，但是最终还是以赚取利润为主要目标的。因此，他们最初的任务是对编写投标价格的建筑成本进行准确的估计。这就需要进行前期调查的工作并且做出施工时间表。等合约批出后，施工方必须提供所有材料并支付其费用，设备，电力，劳动力。业主此时需要进行必要的监督。一个总承包商承担一个建筑整体的责任。从事分包的承建商则需承担建造工程所需的各个工作。例如，管道承包商安装水管，电业承办商安装电气系统，电梯则由电梯承包商安装。他们与总承包商签订合同，费用由总承包商支付。有时候，除了一个总承包商，还有各种专业承包商，如电气和机械承包商，执行工作时需要与业主签订合同。这种承包商被称为间接承包商。他们的工作，由总承包商协调，但它们都是由业主直接联系。还有些时候，业主可以使用设计建造方法同时兼有设计和建筑施工单位的职能。这些单位被称为设计建造承包商。这方面的一个类型的合同聘用的变化是由一户住宅或低层住宅建筑群的开发。在房屋建筑设计和建造的住房，但设计之前需要由购买房屋的业主完成。施工过程管理往往是困难的。因此，一些业主会去寻求专家的协助，这些专家被称为专业施工经理，他们具有丰富的施工经验。施工经理与总承包商进行谈判，并选择其中一个项目。施工经理通常还监督分包商。在施工期间，它们有助于控制成本，加快运送设备和材料，并保持工作的进度。在依法行政，协助设计和建设的情况下，业主可以选择从事建筑项目经理。建筑承包商雇用的劳动力，一般有大工和小工。大工再建筑工程中从事技术活，如木工，管道工，工会成员和电工工会，小工则执行了分配给他们的工作。在施工期间，一切工作都要验收。因此，业主通过建筑师和监理经常进行督查。可能是名为工程员，建筑师或驻地工程师。作为业主的代表实地视察。核查人员必须确保工程符合合同文件的要求，并在安全的条件下进行的责任。这种检查可作出重复。此外，验收还是需要一个或多个政府机构的代表。他们必须确保工程符合法律要求，并负责检查与合同文件是否一致。这种视察一般定期或在某些阶段施工结束以后进行。地方或国家建设部门具有管辖权。这些检查的目的是确保符合当地或国家的建筑规范。以下是传统多层建筑施工的基本程序。建造开始后合同授予开发商，业主可要求开发商开始施工之前签约给或之后签约发出书面通知的同时另一部分工作继续进行。紧接着施工方根据需要获取建筑许可证，例如当地的建设，供水，污水处理，政府机构和公路部门。总承包商的计划和进度详细施工作业以及动员项目设备和人员。分包商得到通知后，做出签订合同的意向或授予分包合同书，然后给出在适当的时候进行通知。在施工前启动，总承包商要进行的一项调查就是邻近结构和地形，这些都要记录在案，并要熟悉当地情况。这项调查结束以后，随即进行布局建设。承建商的现场办事处都建在施工现场或附近。为了安全起见，必须从脚手架上移除的东西，产生的碎片都要运走。下一步，该网架是为建设工程准备的。这项工作为地下室开挖和基础开挖的深度，以及公用事业管道转移找到正确的标高。深挖掘，土方支撑，底部排出。建筑开始于基础上，然后是承重墙和结构框架的施工。梯子，楼梯，或电梯的安装，可让施工人员往返于各个楼层。此外，可安装卷扬机来运送材料。由于建筑高度的上升，管道，电力管道和线路安装以及永久地板，外墙，窗户和构造的影响。在适当的时候，永久的电梯安装。再需要的情况下可以安装防火卷帘。其次，屋顶等地方也需要安装。精加工工序安装有包括以下内容：天花板，瓷砖，墙板，墙壁镶板，水管装置，加热炉，空气调节设备，加热和冷却室装置;自动扶梯;地板，窗户玻璃;活动板，门;电气设备和仪器，包括照明灯具，开关，变压器，控制器，遵照项目的图纸和规格。外地办事处，围栏，桥梁和其他临时建筑，公共设备，如天然气，电力管道，水管，都连接到建筑上。最后，是建筑物内部的打扫和清洗。业主的代表，会给建设工程作最后检查。如果他们满意并认为符合合同文件，那么业主接受该项目，并交给总承包商的一个占用证书，这表明，总承包商已完成建设，建设部门再根据建筑规范的要求发放最后付款。请采纳。
你是哪个省的啊 看看如果可以的话 可以给你一份全面的
%e5%9c%9f%e6%9c%a8%e5%b7%a5%e7%a8%8b给你个链接，自己下载吧
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backing up slowly, choosing to leave his gun trained on the man on the As Grouard inchedbackward, he could see the woman across the room raising her UV li
SCC formwork pressure: Influence of steel rebars Abstract The formwork pressure exerted by a given Self Compacting Concrete (SCC) depends on its thixotropic behavior, on the casting rate and on the shape of the It can moreover be expected that, in the case of a formwork containing steel rebars, these should also play a In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is In second part, a comparison of the theoretical predictions to the experimental measurements of the pressure drop, after the end of casting SCC, was determined and the proposed model was Finally, an extrapolation is suggested of the proposed method to the case of a rectangular formwork containing a given horizontal section of steel rebars, which could allow the prediction of the formwork pressure during Keywords: Fresh concrete; Rheology; Workability; Formwork presure; Thixotropy Introduction In most of the current building codes or technical recommendations [1], [2], [3] and [4], the main parameters affecting formwork pressure during casting are the density of concrete, the formwork dimensions, the pouring rate of concrete, the temperature, and the type of However, it was recently demonstrated that, in the case of SCC, the thixotropic behaviour of the material played a major role [5] P Billberg, Form pressure generated by self-compacting concrete, Proceedings of the 3rd International RILEM Symposium on Self-compacting Concrete, RILEM PRO33 Reykjavik, Iceland (2003), 271–[5], [6], [7] and [8] It can be noted that this influence is in fact indirectly taken into account in the above empirical technical recommendations via the effect of temperature and type of the binder, which are both strongly linked to the ability of the material to build up a structure at rest [9], [10] and [11] During placing, the material indeed behaves as a fluid but, if is cast slowly enough or if at rest, it builds up an internal structure and has the ability to withstand the load from concrete cast above it without increasing the lateral stress against the It was demonstrated in [7] and [8] that, for a SCC confined in a formwork and only submitted to gravity forces, the lateral stress (also called pressure) at the walls may be less than the hydrostatic pressure as some shear stress τwall is supported by the It was also demonstrated that this shear stress reached the value of the yield stress, which itself increased with time because of Finally, if there is no sliding at the interface between the material and the formwork [8], the yield stress (not less or not more) is fully mobilized at the wall and a fraction of the material weight is supported (vertically) by the The pressure exerted by the material on the walls is then lower than the value of the hydrostatic Based on these results, the model proposed by Ovarlez and Roussel [7] predicts a relative lateral pressure σ′ ( ratio between pressure and hydrostatic pressure) at the bottom of the formwork and at the end of casting equal to: (1)and a pressure drop Δσ′(t) after casting equal to: (2)where H is the height of concrete in the formwork in m, Athix the structuration rate in Pa/s [10], R is the casting rate in m/s, e is the width of the formwork in m, g is gravity, t is the time after the end of casting and ρ is the density of the As it can be seen from the above, the key point for the pressure decrease is that the shear stress on each vertical boundary of the formwork equals the static yield stress of the It can then be expected that, in the case of a formwork containing steel rebars, the stress at the surface of the rebars should also play a It is the objective of this paper to start from the model developed by Ovarlez and Roussel [7] and extend it to the case of reinforced As the steel rebars should have a positive effect on formwork design ( decreasing the formwork pressure), this could allow for a further reduction of the formwork In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is In second part, a comparison of the theoretical predictions to the experimental measurements of the pressure drop, after the end of casting SCC, is determined and the proposed model is Finally, an extrapolation is suggested of the proposed method to the case of a rectangular formwork containing a given horizontal section of steel rebars, which could allow the prediction of the formwork pressure during Influence of a vertical steel bar on the pressure decrease inside a cylindrical formwork In this paper, SCC is considered as a yield stress material (in first step, thixotropy is neglected), and, for stresses below the yield stress, SCC behaves as an elastic material [7] In the following, cylindrical coordinates are used with r in the radius direction; the vertical direction z is oriented downwards (see F 1) The top surface (upper limit of the formwork) is the plane z = 0; the formwork walls are at r = R The bottom of the formwork is located at z = H An elastic medium of density ρ is confined between the cylindrical formwork and an internal cylindrical steel rebar defined by the boundary (r = rb) For the boundary condition, the Tresca conditions are imposed everywhere at the walls ( it is assumed that the shear stress at the walls is equal to the yield stress τ00 as argued by Ovarlez and Roussel [7] and demonstrated in [8]) In order to compute the mean vertical stress σzz(z) in the formwork, the static equilibrium equation projected on the z axis on an horizontal slice of material confined between two coaxial rigid cylinders can be written: Evaluation of the structuration rate of SCC at rest The vane test The yield stress of the studied SCC was measured using a concrete rheometer equipped with a vane The vane geometry used in this study consisted of four 10 mm thick blades around a cylindrical shaft of 120 mm The blade height was 60 mm and the vane diameter was 250 The gap between the rotating tool and the external cylinder was equal to 90 mm which is sufficiently large to avoid any scaling effect due to the size of the gravel (Dmax = 10 mm here) Tests were performed for four different resting times after mixing on different samples from the same Of course, working with the same batch does not allow for the distinction between the non-reversible evolution of the behavior due to the hydration of the cement particles and the reversible evolution of the behavior due to thixotropy [9] and [10] It can however be noted that the final age of the studied system ( from the beginning of the mixing step to the last vane test measurement) was of the order of 70 Although Jarny et [13] have recently shown, using MRI velocimetry, that a period of around 30 min exists, for which irreversible effects have not yet become significant compared to reversible ones, the final age of the system in the present study was over this However, no strong stiffening nor softening of the sample was visually spotted nor measured as it will be shown Finally, the data analysis proposed by Estellé et [14] was used for the yield stress The plate test The plate test appears to be a very convenient method to monitor the apparent yield stress evolution of a thixotropic material with It was first developed and used in [8] but more details about its application to other materials than cement can be found in [15] The device is composed of a plate rigidly attached below a The plate is lowered into a vessel containing the SCC ( F 2) The apparent mass of the plate is continuously monitored versus time by recording the balance output with a The balance measurements have an uncertainty of ± 01 The vessel was made of smooth PVC and was cylindrical with a diameter of 200 mm and 200 mm in The plate was placed along the cylinder During the tests, the vessel was filled with material to a height of 200 The plate used was 3 mm thick, 75 mm wide and 100 mm It was covered with sand paper with an average roughness of 200 µ The sand paper was used to avoid any slippage between the material and the plate [8] The distance between the plate and the vessel walls was large enough compared to the size of the constitutive particles that the material can be considered as homogeneous [16] and [17] The height H of the immersed portion of the plate was measured before the start of the To ensure that all tests start with the suspension in similar condition, vibration was applied (frequency of 50 Hz, amplitude of 5 mm) for 30 This step is critical in order to ensure tests Variations between tests performed on the same material in the same experimental conditions were then less than 5% -------------------------------------------------------------------------------- Full-size image (22K) F Schematic of the plate View Within Article The plate test analysis is based on the fact that the slight deformation of the cement paste under its own weight allows for the transfer of a part of this weight to the plate by the mobilization of a shear stress on the This shear stress is equal to the maximum value physically acceptable, which is the yield stress (more details were given in [8], [15], [16] and [17]) The variation in apparent yield stress with time can then be calculated from the measured apparent mass evolution of the plate with time using the following relation: (9)Δτ0(t)=gΔM(t)/2Swhere ΔM(t) is the measured variation in the apparent mass of the plate and S is the immerged Laboratory cylindrical formworks Two columns were simultaneously filled with the studied SCC The columns were made of the same PVC covered with the same sand paper as the plate The columns inner diameters were equal to 100 Each column was 1300 mm The thickness of the plastic wall was 3 A 25 mm diameter steel bar was introduced in the second column (F 3)
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works such as bridges, roads, canals, dams and Civil engineering is the oldest engineering discipline after military engineering, and it was defined to distinguish non-military engineering from military It is traditionally broken into several sub-disciplines including environmental engineering, geotechnical engineering, structural engineering, transportation engineering, municipal or urban engineering, water resources engineering, materials engineering, coastal engineering, surveying, and construction Civil engineering takes place on all levels: in the public sector from municipal through to federal levels, and in the private sector from individual homeowners through to international History of civil engineeringCivil engineering is the application of physical and scientific principles, and its history is intricately linked to advances in understanding of physics and mathematics throughout Because civil engineering is a wide ranging profession, including several separate specialized sub-disciplines, its history is linked to knowledge of structures, materials science, geography, geology, soils, hydrology, environment, mechanics and other Throughout ancient and medieval history most architectural design and construction was carried out by artisans, such as stone masons and carpenters, rising to the role of master Knowledge was retained in guilds and seldom supplanted by Structures, roads and infrastructure that existed were repetitive, and increases in scale were One of the earliest examples of a scientific approach to physical and mathematical problems applicable to civil engineering is the work of Archimedes in the 3rd century BC, including Archimedes Principle, which underpins our understanding of buoyancy, and practical solutions such as Archimedes' Brahmagupta, an Indian mathematician, used arithmetic in the 7th century AD, based on Hindu-Arabic numerals, for excavation (volume) 土木工程是一门学科，专业工程的设计，施工和维护自然的物理和环境建设，包括桥梁，道路，河渠，堤坝和建筑物的工程协议。土木工程是最古老的军事工程后，工程学科，它被定义为区分军事工程非军事工程。这是传统分解成若干子学科包括环境工程，岩土工程，结构工程，交通工程，市政工程或城市，水资源工程，材料工程，海岸工程，测量，施工工程。土木工程需要在所有层次上进行：在从市政公用部门通过联邦的水平，并在私营部门，个别业主通过向国际公司土木工程的历史土木工程是物理和科学原理的应用，它的历史是错综复杂的联系在物理学和数学的了解整个历史的进步。由于土木工程是一个广泛的行业，包括一些独立的专门的子学科，它的历史是联系在一起的结构，材料科学，地理，地质，土壤，水文，环境，机械和其他领域的知识。在整个历史上最古老的和中世纪的建筑设计和施工进行了如石匠和木匠手艺，上升到建筑师的角色。知识是保留在很少的行会和进步所取代。构筑物，道路和基础设施存在的重复，并在规模上升的增量。对科学方法的物理和数学问题适用于土木工程最早的例子之一是阿基米德在公元前3世纪，包括阿基米德的原则，巩固我们的浮力的认识，如阿基米德螺旋切实可行的解决办法的工作。婆罗门，印度数学家，用在公元7世纪算法的基础上，印度教，阿拉伯数字，挖掘（卷）计算。
ma of more days and months and years t
我也是土木专业的，把以前我用的那个发给你参考一下。去看邮箱吧。
SCC formwork pressure: Influence of steel rebars Abstract The formwork pressure exerted by a given Self Compacting Concrete (SCC) depends on its thixotropic behavior, on the casting rate and on the shape of the It can moreover be expected that, in the case of a formwork containing steel rebars, these should also play a In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is In second part, a comparison of the theoretical predictions to the experimental measurements of the pressure drop, after the end of casting SCC, was determined and the proposed model was Finally, an extrapolation is suggested of the proposed method to the case of a rectangular formwork containing a given horizontal section of steel rebars, which could allow the prediction of the formwork pressure during Keywords: Fresh concrete; Rheology; Workability; Formwork presure; Thixotropy Introduction In most of the current building codes or technical recommendations [1], [2], [3] and [4], the main parameters affecting formwork pressure during casting are the density of concrete, the formwork dimensions, the pouring rate of concrete, the temperature, and the type of However, it was recently demonstrated that, in the case of SCC, the thixotropic behaviour of the material played a major role [5] P Billberg, Form pressure generated by self-compacting concrete, Proceedings of the 3rd International RILEM Symposium on Self-compacting Concrete, RILEM PRO33 Reykjavik, Iceland (2003), 271–[5], [6], [7] and [8] It can be noted that this influence is in fact indirectly taken into account in the above empirical technical recommendations via the effect of temperature and type of the binder, which are both strongly linked to the ability of the material to build up a structure at rest [9], [10] and [11] During placing, the material indeed behaves as a fluid but, if is cast slowly enough or if at rest, it builds up an internal structure and has the ability to withstand the load from concrete cast above it without increasing the lateral stress against the It was demonstrated in [7] and [8] that, for a SCC confined in a formwork and only submitted to gravity forces, the lateral stress (also called pressure) at the walls may be less than the hydrostatic pressure as some shear stress τwall is supported by the It was also demonstrated that this shear stress reached the value of the yield stress, which itself increased with time because of Finally, if there is no sliding at the interface between the material and the formwork [8], the yield stress (not less or not more) is fully mobilized at the wall and a fraction of the material weight is supported (vertically) by the The pressure exerted by the material on the walls is then lower than the value of the hydrostatic Based on these results, the model proposed by Ovarlez and Roussel [7] predicts a relative lateral pressure σ′ ( ratio between pressure and hydrostatic pressure) at the bottom of the formwork and at the end of casting equal to: (1)and a pressure drop Δσ′(t) after casting equal to: (2)where H is the height of concrete in the formwork in m, Athix the structuration rate in Pa/s [10], R is the casting rate in m/s, e is the width of the formwork in m, g is gravity, t is the time after the end of casting and ρ is the density of the As it can be seen from the above, the key point for the pressure decrease is that the shear stress on each vertical boundary of the formwork equals the static yield stress of the It can then be expected that, in the case of a formwork containing steel rebars, the stress at the surface of the rebars should also play a It is the objective of this paper to start from the model developed by Ovarlez and Roussel [7] and extend it to the case of reinforced As the steel rebars should have a positive effect on formwork design ( decreasing the formwork pressure), this could allow for a further reduction of the formwork In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is In second part, a comparison of the theoretical predictions to the experimental measurements of the pressure drop, after the end of casting SCC, is determined and the proposed model is Finally, an extrapolation is suggested of the proposed method to the case of a rectangular formwork containing a given horizontal section of steel rebars, which could allow the prediction of the formwork pressure during Influence of a vertical steel bar on the pressure decrease inside a cylindrical formwork In this paper, SCC is considered as a yield stress material (in first step, thixotropy is neglected), and, for stresses below the yield stress, SCC behaves as an elastic material [7] In the following, cylindrical coordinates are used with r in the radius direction; the vertical direction z is oriented downwards (see F 1) The top surface (upper limit of the formwork) is the plane z = 0; the formwork walls are at r = R The bottom of the formwork is located at z = H An elastic medium of density ρ is confined between the cylindrical formwork and an internal cylindrical steel rebar defined by the boundary (r = rb) For the boundary condition, the Tresca conditions are imposed everywhere at the walls ( it is assumed that the shear stress at the walls is equal to the yield stress τ00 as argued by Ovarlez and Roussel [7] and demonstrated in [8]) In order to compute the mean vertical stress σzz(z) in the formwork, the static equilibrium equation projected on the z axis on an horizontal slice of material confined between two coaxial rigid cylinders can be written: Evaluation of the structuration rate of SCC at rest The vane test The yield stress of the studied SCC was measured using a concrete rheometer equipped with a vane The vane geometry used in this study consisted of four 10 mm thick blades around a cylindrical shaft of 120 mm The blade height was 60 mm and the vane diameter was 250 The gap between the rotating tool and the external cylinder was equal to 90 mm which is sufficiently large to avoid any scaling effect due to the size of the gravel (Dmax = 10 mm here) Tests were performed for four different resting times after mixing on different samples from the same Of course, working with the same batch does not allow for the distinction between the non-reversible evolution of the behavior due to the hydration of the cement particles and the reversible evolution of the behavior due to thixotropy [9] and [10] It can however be noted that the final age of the studied system ( from the beginning of the mixing step to the last vane test measurement) was of the order of 70 Although Jarny et [13] have recently shown, using MRI velocimetry, that a period of around 30 min exists, for which irreversible effects have not yet become significant compared to reversible ones, the final age of the system in the present study was over this However, no strong stiffening nor softening of the sample was visually spotted nor measured as it will be shown Finally, the data analysis proposed by Estellé et [14] was used for the yield stress The plate test The plate test appears to be a very convenient method to monitor the apparent yield stress evolution of a thixotropic material with It was first developed and used in [8] but more details about its application to other materials than cement can be found in [15] The device is composed of a plate rigidly attached below a The plate is lowered into a vessel containing the SCC ( F 2) The apparent mass of the plate is continuously monitored versus time by recording the balance output with a The balance measurements have an uncertainty of ± 01 The vessel was made of smooth PVC and was cylindrical with a diameter of 200 mm and 200 mm in The plate was placed along the cylinder During the tests, the vessel was filled with material to a height of 200 The plate used was 3 mm thick, 75 mm wide and 100 mm It was covered with sand paper with an average roughness of 200 µ The sand paper was used to avoid any slippage between the material and the plate [8] The distance between the plate and the vessel walls was large enough compared to the size of the constitutive particles that the material can be considered as homogeneous [16] and [17] The height H of the immersed portion of the plate was measured before the start of the To ensure that all tests start with the suspension in similar condition, vibration was applied (frequency of 50 Hz, amplitude of 5 mm) for 30 This step is critical in order to ensure tests Variations between tests performed on the same material in the same experimental conditions were then less than 5% -------------------------------------------------------------------------------- Full-size image (22K) F Schematic of the plate View Within Article The plate test analysis is based on the fact that the slight deformation of the cement paste under its own weight allows for the transfer of a part of this weight to the plate by the mobilization of a shear stress on the This shear stress is equal to the maximum value physically acceptable, which is the yield stress (more details were given in [8], [15], [16] and [17]) The variation in apparent yield stress with time can then be calculated from the measured apparent mass evolution of the plate with time using the following relation: (9)Δτ0(t)=gΔM(t)/2Swhere ΔM(t) is the measured variation in the apparent mass of the plate and S is the immerged Laboratory cylindrical formworks Two columns were simultaneously filled with the studied SCC The columns were made of the same PVC covered with the same sand paper as the plate The columns inner diameters were equal to 100 Each column was 1300 mm The thickness of the plastic wall was 3 A 25 mm diameter steel bar was introduced in the second column (F 3)