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土木工程英文文獻,建筑方面的英語論文

  • 英語學習網
  • 2024-01-18

土木工程英文文獻?土木工程專業的英文論文格式均以美國土木工程師協會出版社發布的標準格式為準。英語論文用激光打印機打印,打印稿為黑白稿,彩色打印件會影響出版效果。版心:a4紙,上、下頁邊距3.5 cm,左、右頁邊距均為3.25 mm。那么,土木工程英文文獻?一起來了解一下吧。

土木工程1500詞英語論文

(4.5 )

Strength criteria for isotropic rock material

(4.5.1)

Types of strength criterion

A peak strength criterion is a relation between stress components which will permit the peak strengths developed under various stress combinations to be predicted. Similarly, a residual strength criterion may be used to predict residual strengths under varying stress conditions. In the same way, a yield criterion is a relation between stress components which is satisfied at the onset of permanent deformation. Given that effective stresses control the stress-strain behaviour of rocks, strength and yield criteria are best written in effective stress form. However, around most mining excavations, the pore-water will be low, if not zero, and so .For this reason it is common in mining rock mechanics to use total stresses in the majority of cases and to use effective stress criteria only in special circumstance.

The data presented in the preceding sections indicate that the general form of the peak strength criterion should be

(4.8)

This is sometimes written in terms of the shear, and normal stresses, on a particular plane in the specimen:

(4.9)

Because the available data indicate that the intermediate principal stress, has less influence on peak strength than the minor principal stress, all of the criteria used in practice are reduced to the form

(4.10)

4.5.2 Coulomb’s shear strength criterion

In one of the classic paper of rock and of engineering science, Coulomb(1977) postulated that the shear strengths of rock and of soil are made up of two part – a constant cohesion and a normal stress-dependent frictional component. (Actually, Coulomb presented his ideas and calculations in terms of forces; the differential concept of stress that we use today was not introduced until the 1820s.) Thus, the shear strength that can be developed on a plane such as ab in figure 4.22 is

(4.11)

Where c=cohesion and Ф= angle of internal friction.

Applying the stress transformation equation to the case shown in figure 4.22 givesAnd

Substitution forand s = τ in equation 4.11 and rearranging gives the limiting stress condition on any plane defined by β as

(4.12)

There will be a critical plane on which the available shear strength will be first reaches as б1 is increased. The Mohr circle construction of Figure 4023a given the orientation of this critical plane as

(4.13)

This result may also be obtained by putting d(s-τ)/dβ = 0

For the critical plane, sin2β = cosФ, cos2β = -sinФ, and equation 4.12 reduces to

(4.14)

This linear relation betweenand the peak value of is shown in Figure 4.23b. Note that the slope of this envelope is related to Ф by the equation

(4.15)

And that the uniaxial compressive strength is related to c and Ф by

(4.16)

If the Coulomb shown in Figure 4.23b is extrapolated to = 0, it will intersect the axis at an apparent value of uniaxial strength of the material given by

(4.17)

The measurement of the uniaxial tensile strength of rock is fraught with difficulty. However, when it is satisfactorily measured, it takes values that are generally lower than those predicted value of uniaxial tensile stress, =0.

Although it is widely used, Coulomb’s criterion is not a particularly satisfactory peak strength criterion for rock material. The reasons for this are:

(a) It implies that a major shear fracture exist at peak strength. Observations such as those made by Wawersik and Fairhurst(1970) show that is not always the case.

(b) It implies a direction of shear failure which does not always agree with experimental observations.

(c) Experimental peak strength envelopes are generally non-linear. They can be considered linear only over limited ranges of or.

For these reasons, other peak strength criteria are preferred for intact rock. However, the Coulomb criterion can provide a good representation of residual strength conditions, and more particularly, of the shear strength of discontinuities in rock (section 4.7).

4.5.3 Griffith crack theory

In another of the classic papers of engineering science, Griffith (1921) postulated that fracture of brittle materials, such as steel and glass, is initial at tensile stress concentrations at the tips of minute, thin cracks (now referred to as Griffith based his determination of the conditions under which a crack would extend on his energy instability concept:

A crack will extend only when the total potential energy of the system of applied forces and material decreases or remains constant with an increase in crack length.

ROCK STRENGTH AND DEFORMABILITY

For the case in which the potential energy of the applied forces is taken to be constant throughout, the criterion for crack extension may be written

(4.19)

Where c is a crack length parameter, We is the elastic energy stored around the crack and Wd is the surface energy of the crack surfaces.

Griffith (1921) applied this theory to the extension of an elliptical crack of initial length 2c that is perpendicular to the direction of loading of a plate of unit thickness subjected to a uniaxial tensile stress, б. He found that the crack will extend when

(4.20)

Where α is the surface energy per unit area of the crack surfaces (associated with the rupturing of atomic bonds when the crack is formed), and E is the Young’s modulus of the uncracked material.

It is important to note that it is the surface energy, α, which is the fundamental material property involved here. Experimental studies show that, for rock, a preexisting crack does not extend as a single pair of crack surface, but a fracture zone containing large numbers of very small cracks develops ahead of the propagating crack 9FIGURE 4.25). In this case, it is preferable to treat α as an apparent surface energy to distinguish it from the surface energy which may have a significantly smaller value.

It is difficult, if not impossible, to correlate the results of different types of direct and indirect tensile test on rock using the average tensile stress in the fracture zone as the basic material property. For this reason, measurement of the ‘tensile strength’ of rock has not been discussed in this chapter. However, Hardy(1973) was to obtain good correlation between the results of a rang of tests involving tensile fracture when the apparent surface energy was used as the unifying material property.

Griffith (1924) extended his theory to the case of applied compressive stresses. Neglecting the influence of friction on the cracks which will close under compression, and assuming the elliptical crack will propagate from the points of maximum tensile stress concentration (P IN Figure 4.26), Griffith obtained the following criterion for crack extension in plane compression:

(4.20)

Where is the uniaxial tensile strength of the uncracked material (a positive number).

This criterion can also be expressed in terms of the shear stress, τ , and the normal stress,acting on the plane containing the major axis of the crack:

(4.21)

The envelopes given by equations 4.20. and 4.21 are shown in Figure 4.27. Note that this theory predicts that the uniaxial compressive compressive stress at crack extension will always be eight times the uniaxial tensile strength.

建筑專業英文文獻網站

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 buildings. Civil engineering is the oldest engineering discipline after military engineering, and it was defined to distinguish non-military engineering from military engineering. 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 engineering. 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 companies.

History of civil engineering

Civil engineering is the application of physical and scientific principles, and its history is intricately linked to advances in understanding of physics and mathematics throughout history. 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 fields.

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 builder. Knowledge was retained in guilds and seldom supplanted by advances. Structures, roads and infrastructure that existed were repetitive, and increases in scale were incremental.

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' screw. Brahmagupta, an Indian mathematician, used arithmetic in the 7th century AD, based on Hindu-Arabic numerals, for excavation (volume) computations.

土木工程是一門學科,專業工程的設計,施工和維護自然的物理和環境建設,包括橋梁,道路,河渠,堤壩和建筑物的工程協議。

土木工程外文期刊

土木工程專業的英文論文格式

導語:土木工程專業的英文的論文格式包括哪些內容呢?土木工程是建造各類工程設施的科學技術的統稱。下面是我分享的土木工程專業的英文的論文格式,歡迎閱讀!

土木工程專業的英文論文格式均以美國土木工程師協會出版社發布的標準格式為準。

英語論文用激光打印機打印,打印稿為黑白稿,彩色打印件會影響出版效果。

版心:a4紙,上、下頁邊距3.5 cm,左、右頁邊距均為3.25 mm。論文內容寬不得超過14.5cm, 長不得超過22.5cm。

字體和字號:正文,標題,作者聯絡信息和圖表中的文字均為times new roman 12號字。可以跟據需要使用同類字體中的粗體,斜體。

行距:單倍行距。

頁碼: 論文正文和文后所附圖例都需添加頁碼。頁碼為阿拉伯數字,位于頁面下方居中。

文體: 文章應語法正確,技術用詞準確。標題應該以最簡潔的語言概括文章內容。如果標題較長,請采用title: subtitle的形式。

數學公式:文中的數學公式不得手寫,必須打印。公式如果在文中多次被引用,應該編號。公式之間,公式和正文之間都應該空一行。

土木工程論文英文參考文獻

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 formwork. It can moreover be expected that, in the case of a formwork containing steel rebars, these should also play a role. In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is studied. 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 validated. 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 casting.

Keywords: Fresh concrete; Rheology; Workability; Formwork presure; Thixotropy

1. 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 binder.

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), pp. 271–280.[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 formwork. 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 walls. It was also demonstrated that this shear stress reached the value of the yield stress, which itself increased with time because of thixotropy. 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 formwork. The pressure exerted by the material on the walls is then lower than the value of the hydrostatic pressure.

Based on these results, the model proposed by Ovarlez and Roussel [7] predicts a relative lateral pressure σ′ (i.e. 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 concrete.

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 material. 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 role. 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 formworks. As the steel rebars should have a positive effect on formwork design (i.e. decreasing the formwork pressure), this could allow for a further reduction of the formwork size.

In first part, the specific case of a cylindrical formwork containing a single cylindrical steel rebar is studied. 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 validated. 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 casting.

2. 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 Fig. 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 (i.e. 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:

3.2. Evaluation of the structuration rate of SCC at rest

3.2.1. The vane test

The yield stress of the studied SCC was measured using a concrete rheometer equipped with a vane tool. The vane geometry used in this study consisted of four 10 mm thick blades around a cylindrical shaft of 120 mm diameter. The blade height was 60 mm and the vane diameter was 250 mm. 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 batch. 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 (i.e. from the beginning of the mixing step to the last vane test measurement) was of the order of 70 min. Although Jarny et al. [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 period. However, no strong stiffening nor softening of the sample was visually spotted nor measured as it will be shown later. Finally, the data analysis proposed by Estellé et al. [14] was used for the yield stress calculation.

3.2.2. 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 time. 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 balance. The plate is lowered into a vessel containing the SCC (cf. Fig. 2). The apparent mass of the plate is continuously monitored versus time by recording the balance output with a computer. The balance measurements have an uncertainty of ± 0.01 g. The vessel was made of smooth PVC and was cylindrical with a diameter of 200 mm and 200 mm in height. The plate was placed along the cylinder axis. During the tests, the vessel was filled with material to a height of 200 mm. The plate used was 3 mm thick, 75 mm wide and 100 mm long. It was covered with sand paper with an average roughness of 200 μm. 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 test. 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 s. This step is critical in order to ensure tests reproducibility. Variations between tests performed on the same material in the same experimental conditions were then less than 5%.

--------------------------------------------------------------------------------

Full-size image (22K)

Fig. 2. Schematic of the plate test.

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 plate. 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 surface.

3.2.3. 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 test. The columns inner diameters were equal to 100 mm. Each column was 1300 mm high. The thickness of the plastic wall was 5.3 mm. A 25 mm diameter steel bar was introduced in the second column (Fig. 3).

土木工程外文文獻網站

國家標準土木工程主要參考文獻有哪些

各種規范 國家頒布的。看你土木工程那個方向 就看專業方面的書

工民建

道橋

水利

給排水

地下

誰知道土木工程專業英語的參考文獻/

Standard Handbook for Civil Engineers (Handbook) by Jonathan Ricketts, M. Loftin and Frederick Merritt

Civil Engineering Handbook,by W.F.Chen

The Architect's Portable Handbook, by PAT GUTHRIE,McGraw-Hill Company.

這些都是PEC土木工程英語證書考試的輔導用書。應該是最好的了。內容覆蓋:鋼結構、混凝土結構、砌體結構、地基與基礎、建筑材料與施工技術。主要考察土木工程類專業術語的閱讀與理解。

本科畢業生土木工程專業參考文獻怎么寫

參考文獻就是你所引用的文字的來源,比如參考《建筑施工手冊》2015版 xx編著,謝謝

《43-參考文獻格式國家標準GB7714-87》txt

43-參考文獻格式國家標準GB7714-87 txt附件已上傳到,點選免費:

內容預覽:

參考文獻格式國家標準(zt) 中華人民共和國國家標準 UDC 025.32 GB 7714-87 文后參考文獻著錄規則 Descriptive rules for bibliographic references 國家標準局 1987 - 05 - 05 批準 1988 - 01 - 01 實施 l 引言 1.1 本標準規定了各型別出版物中的文后參考文獻的著錄專案、著錄順序、著錄用的符號 、各個著錄專案的著錄方法以及參考文獻標注法。

以上就是土木工程英文文獻的全部內容,EI:《工程索引》(The Engineering Index,簡稱EI)創刊于1884年,是美國工程信息公司(Engineering information Inc.)出版的著名工程技術類綜合性檢索。EI每月出版1期。

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