特黄毛片杨钰莹-特黄三级-特黄三级毛片-特黄色毛片-91av视频在线观看-91av视频在线免费观看

當前位置: 首頁 > 學英語

土木工程英文文獻,建筑方面的英語論文

  • 學英語
  • 2024-01-18

土木工程英文文獻?土木工程專業(yè)的英文論文格式均以美國土木工程師協(xié)會出版社發(fā)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(yè)英文文獻網(wǎng)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(yè)工程的設計,施工和維護自然的物理和環(huán)境建設,包括橋梁,道路,河渠,堤壩和建筑物的工程協(xié)議。

土木工程外文期刊

土木工程專業(yè)的英文論文格式

導語:土木工程專業(yè)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(tǒng)稱。下面是我分享的土木工程專業(yè)的英文的論文格式,歡迎閱讀!

土木工程專業(yè)的英文論文格式均以美國土木工程師協(xié)會出版社發(fā)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(lián)絡信息和圖表中的文字均為times new roman 12號字。可以跟據(jù)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(shù)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(shù)學公式:文中的數(shù)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(wǎng)站

國家標準土木工程主要參考文獻有哪些

各種規(guī)范 國家頒布的。看你土木工程那個方向 就看專業(yè)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(yè)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(yè)術語的閱讀與理解。

本科畢業(yè)生土木工程專業(yè)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(guī)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(guī)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(chuàng)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。

猜你喜歡

主站蜘蛛池模板: 久久福利免费视频 | 自慰无码一区二区三区 | 另类二区 | 久久国产精品99久久久久久丝袜 | 99在线精品免费视频九九视 | 日日夜夜爱爱 | 在线不卡的av | 2020天天谢天天吃天天麻豆v | 男人晚上看的网址 | 免费观看午夜视频 | 草av| 中国农村妇女hdxxxx | 激情综合激情五月俺也去 | 香港三日本8a三级少妇三级99 | 欧美日韩精品一区二区在线播放 | 成人免费在线播放 | 农村女人十八毛片a级毛片 农村人伦偷精品视频a人人澡 | 国产精品久久久久久久成人午夜 | 爱射综合| 四虎院影亚洲永久 | 亚洲伊人成综合网 | 国产精品免费福利久久 | 99国产精品无码 | 亚洲一区二区无码偷拍 | 东京无码熟妇人妻av在线网址 | 国产精品噜噜噜66网站 | 日本成人午夜 | 日韩一区二区免费在线观看 | 国产乱人伦精品免费 | 国偷自产一区二区免费视频 | 欧美品牌jizzhd欧美 | av观看在线观看 | 久久综合久久综合九色 | 成人自拍视频网站 | 婷婷综合久久狠狠色99h | 久久免费看少妇高潮 | 999精品视频一区二区三区 | 亚洲精品久久区二区三区蜜桃臀 | 国产又粗又黄又爽又硬的免费视频 | 久久五月天婷婷 | 国产高清免费在线观看 | 干成人网| 亚洲人妻av伦理 | 少妇性l交大片免费观看 | 国产公妇伦在线观看 | 不良网站在线免费观看 | 黄色理论片| 亚洲欧洲日韩在线 | 性――交――性――乱视频 | 亚洲精品美女 | 久久久久久国产精品无码下载 | 无码人妻毛片丰满熟妇区毛片 | 国产在线精品成人一区二区 | 久久嫩草视频 | 午夜色网 | 69xx网站| 欧美成人综合色 | 久久午夜网站 | 国产电影无码午夜在线播放 | 欧美视频四区 | 黄色高潮视频 | 波多野结衣办公室33分钟 | 操碰av| 中文有码无码人妻在线 | 亚洲国产成人精品久久久国产成人 | 爱爱视频网址 | 天堂网av在线播放 | 91精品视频一区二区三区 | 国产日韩欧美不卡在线二区 | 狠狠久久精品中文字幕无码 | 中文av在线播放 | 高清国产一区二区三区四区五区 | 狠狠躁夜夜躁人人爽天天 | 午夜伦4410yy妇女久久v | 欧美一性一乱一交一视频 | 国产一区二区三区影院 | 国产内射爽爽大片视频社区在线 | 综合久久综合 | 亚洲草草网 | 久久精品欧美日韩精品 | 亚洲日韩一页精品发布 | 欧美黑人xxxⅹ高潮交 | 骚虎视频在线观看 | 国产裸体永久免费视频网站 | 国产伦精品一区二区三区视频免费 | 性欧美高清 | 色综合久久久久久久 | 亚洲一区二区三区在线观看网站 | 甄宓高h荡肉呻吟np 正在播放国产老头老太色公园 | 台湾亚洲精品一区二区tv | 巨爆乳无码视频在线观看 | 亚洲精品尤物 | 国产欧美日韩在线 | 初尝黑人巨砲波多野结衣 | 久久久久久久久福利 | 香蕉久久av一区二区三区 | 国产三级按摩推拿按摩 | 水野朝阳av一区二区三区 | 国产一级片网址 | 国产一在线观看 | 激情综合色综合啪啪五月丁香 | 玖玖免费| 老鲁夜夜老鲁 | 中文字幕av在线免费观看 | 在线有码视频 | 天天看片夜夜爽 | 亚洲色图欧美视频 | 成人精品视频在线看 | 在线观看日韩视频 | 日韩欧美视频在线免费观看 | 国产精品日韩精品欧美精品 | 少妇伦子伦情在线观看 | 男女吃奶做爰猛烈紧视频 | 牛牛影视一区二区三区免费看 | 人妻无码视频一区二区三区 | 熟妇好大好深好满好爽 | 在线天堂1 | 日本欧美一区二区 | 亚洲精品丝袜日韩 | 北条麻妃99精品青青久久 | 日本高清视频在线播放 | 免费无码午夜福利片69 | 啪免费| 99国产精品欧美久久久久的广告 | 日韩第八页 | 中文在线字幕观 | 丁香花在线观看免费观看图片 | 美一女一无一伦一性一交 | 日本精品一二区 | 日本人熟老妇 | 亚洲日韩乱码久久久久久 | 欧美性受xxxx黑人xyx性 | 成人性做爰aaa片免费 | 欧美色aⅴ欧美综合色 | 久久欧洲 | 欧美日韩一区在线 | 久久毛片网站 | 久久久久久久97 | 欧美性生交大片免费视频 | 非洲黑人毛片 | 夜色www国产精品资源站 | 亚洲日本va午夜中文字幕一区 | 色综合国产 | 国产图区| 婷婷射| 欧美一区二区三区免费视频 | 300部国产真实乱 | h黄动漫日本www免费视频网站 | 99精品免费久久久久久久久 | 国产边摸边吃奶边做爽视频 | 国产精品老女人 | 国产a在亚洲线播放 | 黄色av网址在线观看 | 荒岛淫众女h文小说 | 日本成人免费视频 | 国产精品一区二区三区在线播放 | 日韩区欧美久久久无人区 | 91视频福利| 国产成人无码a区精油按摩 蜜桃久久精品成人无码av | 天天舔天天射 | www91av| 久久久久久一区国产精品 | 中文字幕第一页在线播放 | av免费观看入口 | 久操视频免费观看 | 四虎影库在线永久影院免费观看 | 亚洲日韩在线观看免费视频 | 免费无码肉片在线观看 | 亚洲精品日韩欧美 | 国产精品夜色一区二区三区 | 欧美极品少妇xxxxⅹ免费视频 | 一本久久伊人热热精品中文字幕 | 久久精品国产99久久6 | 男阳茎进女阳道视频大全 | 亚洲欧美日韩精品在线 | 中文字幕第2页 | 久久99精品久久久久久国产越南 | 中文字幕二 | 欧美亚洲另类视频 | 久久中文视频 | 亚洲第一成网站 | 欧美日本国产欧美日本韩国99 | 人妻少妇精品视频一区二区三区 | 久操视频在线播放 | 国产熟妇久久777777 | 1000部精品久久久久久久久 | 精品久久人人妻人人做精品 | 欧美日韩一区二区在线观看 | 免费精品午夜 | 成人高潮片免费 | 国产一级二级视频 | 午夜老湿机 | 欧美人与性动交α欧美精品 | 免费黄色毛片视频 | 国产精品美女www爽爽爽视频 | 亚洲欧美xxx | 亚洲精品国产品国语在线观看 | 国产伦子伦视频在线观看 | 97视频人人免费看 | 日韩精品色 | 岳的奶又大又白又紧在线观看 | 国产精品无码av在线播放 | 免费一级大片 | 一本大道久久精品懂色aⅴ 一本大道久久卡一卡二卡三乱码 | 国产精品久久久久久久久久久久久 | 国产女主播视频一区二区 | 熟女毛片 | 久久99成人免费 | 精品国产免费人成网站 | 免费高清欧美大片在线观看 | 噼里啪啦在线看免费观看视频 | 欧美mv日韩mv国产网站 | 永久看看免费大片 | 综合网视频 | 影音先锋人妻啪啪av资源网站 | 无套内谢孕妇毛片免费看看 | 成人久久免费网站 | 国产a久久 | 欧美乱妇15p | 无码av免费毛片一区二区 | 成人免费看片载 | 91精品久久久久久久久久入口 | 中文日本在线 | 日本内射精品一区二区视频 | 国产精品av久久久久久无 | 精品欧美一区二区久久久 | 国产欧美精品一区二区三区 | 亚洲一本在线观看 | 久久久久国产视频 | 亚洲浮力影院久久久久久 | 久久久久久久久毛片精品 | 天天射天天舔 | 免费欧美一级 | 性生活在线视频 | 99久久久无码国产精品秋霞网 | 亚洲欧美久久 | 成年18网站免费进入夜色 | 亚洲美女中文字幕 | 9l视频自拍蝌蚪9l视频成人 | 精品久久久久久18免费网站 | 九九免费在线视频 | 成人午夜电影福利免费 | 蜜臀av性久久久久蜜臀aⅴ麻豆 | 999国产精品999久久久久久 | 成色视频| 欧美日韩在线一区二区三区 | 亚洲色成人www永久网站 | 用力来高潮了再用力91 | 中文字幕乱码免费 | 国产精品99久久久久人最新消息 | 九色av| 亚洲精品v日韩精品 | 日日免费视频 | 在线观看色视频 | 国产精品久久久久9999鸭 | 免费欧美一级 | 日本一区二区三区精品视频 | 韩国bj大尺度vip福利网站 | 在线免费黄色网 | 国产浮力第一页 | 久久久久国产精品www | 免费黄色小视频 | 国产精品区在线观看 | 国产农村妇女精品久久 | 亚洲同性同志一二三专区 | 国产精品久久久久影院老司 | 日韩av在线看 | 粉嫩久久久久久久极品 | 五十路熟妇高熟无码视频 | 伦理一级片 | 老外和中国女人毛片免费视频 | 亚洲午夜无码毛片av久久 | 人妻少妇精品中文字幕av | 亚洲天堂网一区二区 | 伊人www22综合色 | 久久久久久久久久久久久国产 | 日韩人妻无码精品系列 | 日本精品视频在线观看 | 红杏亚洲影院一区二区三区 | 麻豆一区二区三区蜜桃免费 | 亚洲国产伊人 | 97在线观看永久免费视频 | 久久精品国产69国产精品亚洲 | 这里有精品| 日本美女视频一区 | 天天爽影院一区二区在线影院 | 国产又粗又长又黄视频 | 国产看真人毛片爱做a片 | 亚洲乱码在线 | 天堂无乱码| 中文在线字幕观看 | 欧美日韩在线观看精品 | 91精品国产闺蜜国产在线闺蜜 | 天天天天躁天天爱天天碰2018 | 日本少妇aa特黄毛片亚洲 | 一本色综合亚洲精品蜜桃冫 | 亚洲va欧美va人人爽春色影视 | 国产靠逼视频 | 永久免费的啪啪网站免费观看浪潮 | 精品国产一区二区三区久久久狼 | 婷婷五月小说 | 亚洲成人精品av | 国产真实乱子伦精品视频 | 波多野结衣av一区二区全免费观看 | 国产97色在线 | 色哟哟一区二区三区 | 久久av中文字幕 | 99久久精品国产一区二区三区 | 91久久久一线二线三线品牌 | 日韩欧美中文字幕公布 | 国产色片在线观看 | 国产精品一区二区三区在线 | 日本一级淫片免费啪啪琪琪 | 一区二区乱子伦在线播放 | 欧美人与动物xxxxx | 亚洲成a人v欧美综合天堂麻豆 | 亚洲性无码一区二区三区 | 久久w5ww成w人免费 | 人人爽人人澡人人人妻 | 五月激情小说 | 免费在线观看网址 | xx中文字幕乱偷avxx | 成年人国产精品 | va婷婷| 毛片毛片毛片毛片毛片毛片毛片毛片毛片 | 无尽夜久久久久久久久久 | 好吊妞视频988在线播放 | 成人天堂视频在线观看软件 | 91毛片网| 久久一区国产 | 无码专区无码专区视频网址 | 国产特级全黄寡妇毛片 | 免费看特级毛片 | 黄色片国产 | 日本免费网站 | 98婷婷狠狠成人免费视频 | 自拍超碰在线 | 国产精品一v二v在线观看 | 久久久久久欧美精品se一二三四 | 丰满人妻一区二区三区免费视频 | 精品一区二区在线观看视频 | 色视频免费看 | 亚洲色图激情 | 欧美视频福利 | 欧美成年人在线观看 | 国产内射爽爽大片 | 欧美色插 | 法国极品成人h版 | 亚洲不卡中文字幕无码 | 好吊妞视频这里只有精品 | 中文字幕永久视频 | av在线中文字幕不卡电影网 | 亚洲人成人一区二区在线观看 | 1000部拍拍拍18勿入免费视频下载 | 久久99国产综合精品免费 | 国产一区精品在线观看 | 久久精品久久精品久久 | 久久久全国免费视频 | 久久69| 人妻av中文系列 | 综合久久一区 | 国产麻豆乱码精品一区二区三区 | 精品久久久久久成人av | 免费日批视频 | 国产精品4区 | 亚洲中文字幕无码中文字在线 | 日韩一三区 | 国产99视频精品免费视频7 | 国产人妖视频一区二区 | 国内精品第一页 | 噜噜噜久久亚洲精品国产品 | 青青草在线视频网站 | 777久久久 | 欧美精品三区 | 乱人伦av | 久久99精品久久久久久牛牛影视 | avtt香蕉久久 | 视频在线观看一区二区三区 | 激情欧美日韩一区二区 | 一起操网站 | 欧美午夜激情影院 | 日韩在线激情视频 | 伊人伊人鲁 | 女同互慰高潮呻吟免费播放 | 国产免费内射又粗又爽密桃视频 | 黑人邻居太猛中文字幕hd | 色狠狠操| 大学生a做爰免费观看 | 中文在线а天堂中文在线新版 | 国产毛片毛片毛片毛片毛片 | 性欧美18一19内谢 | 免费看高清毛片 | 毛片在线免费观看视频 | 国产精品人人爽人人做av片 | 黄色一级网 | 又爽又大又黄a级毛片在线视频 | 欧美h网站 | 国产精品无码专区 | 性欧美丰满熟妇xxxx性仙踪林 | 亚洲精品国产品国语在线观看 | 日本做爰全过程免费的叫床 | 99免费观看视频 | 亚洲欧美日韩天堂 | 一本大道色婷婷在线 | 天天做爰裸体免费视频 | 在线看av网址 | 粉嫩绯色av一区二区在线观看 | 黄网视频在线观看 | 成人喂奶露着大乳 | 91九色porn | 欧美色综合网站 | 99色综合网 | 免费一级片观看 | 夜晚福利视频 | 欧美激情一区二区 | 精品人妻无码专区在线无广告视频 | 成人性生交大片免费看vrv66 | 麻豆91精品91久久久的优点 | 麻豆av一区二区天美传媒 | 樱桃视频一区二区三区 | 337p日本欧洲亚大胆精80 | 国产91色在线 | 免费 | 久久99亚洲精品久久99果 | 日本边添边摸边做边爱的网站 | 国产精品性视频一区二区 | 国内a∨免费播放 | 国产美a三级三级看三级 | 亚洲日韩在线中文字幕综合 | 欧美成人免费全部 | 在线免费观看的av | 久久久中文字幕日本无吗 | 黄色午夜影院 | 18禁高潮出水呻吟娇喘蜜芽 | 一本大道熟女人妻中文字幕在线 | 日韩毛片中文字幕 | 荷兰av| 日韩视频二区 | 国产一级淫片免费放大片 | 很黄很色60分钟在线观看 | 天天插天天爱 | 国产妇女视频 | 色欲av亚洲一区无码少妇 | 日本特黄特色a大片免费高清观看视频 | 午夜啪视频 | 黄色小视频网站免费 | 丁香婷婷在线观看 | 成人自拍视频在线 | 欧美日韩一区二区三区视频播放 | 男女毛片视频 | 在线观看黄网址 | 108种啪姿势大全动态图 | 欧美日韩一区二区三区视频 | 精品久久国产视频 | 久久99国产精品视频 | 亚洲欧美一区二区三区不卡 | 羞羞色院91蜜桃 | 看全色黄大色大片60岁 | 久久综合久久鬼色 | 国内精品久久久久久久影视红豆 | 日韩视频一区二区在线观看 | 九九热精品 | 国产精品夜夜春夜夜爽 | 91中文字幕在线观看 | 美女黄18以下禁止观看 | 老色批永久免费网站www | 国产精品99久久久久久大便 | 美女少妇av | 中文字幕 欧美激情 | 国产精品 欧美日韩 | 国产69精品久久久久人妻刘玥 | 少妇一晚三次一区二区三区 | 欧美黑人一区二区 | 欧美搡bbbbb搡bbbbb | 久久丫精品国产 | 国产精品久久久久久久久久免 | 深夜视频免费在线观看 | 性――交――性――乱 | 久久国色 | 91麻豆精品91久久久久同性 | 中文字幕免费播放 | 欧洲男女做爰免费视频 | 西野翔之公侵犯中文字幕 | 日日草| 精品国产性色无码av网站 | 激情麻豆 | 在线天堂www在线 | 一区二区三区在线 | 欧 | 国产精品免费看久久久 | 图书馆的女友动漫在线观看 | 国产区av | 国产日批视频在线观看 | a免费观看大片 | 欧美福利网站 | 99热精品久久只有精品 | 国产v亚洲v天堂a无码 | 少妇呻吟白浆高潮啪啪69 | 亚洲天堂视频在线观看 | av毛片在线免费观看 | 欧美亚洲国产一区二区三区 | 亚洲国产精品无码久久青草 | 亚洲欧美韩国 | 中文字幕乱码久久午夜不卡 | 国产一区二区黑人欧美xxxx | 国产成人鲁鲁免费视频a | 黄色a毛片| 三级自拍视频 | 秋霞一级视频 | 深夜成人福利视频 | 久草www | 成人免费毛片东京热 | 日本欧美久久久免费播放网 | 一区二区三区日韩在线 | 一二三区乱码2021 | 九色丨蝌蚪pony蜜桃臀 | 亚洲精品无码久久 | 亚洲成人午夜av | 高h禁伦亲女1v2 | 黑人巨大精品一区二区 | 国产一区二区三区视频在线 | 中文字幕人成乱码熟女香港 | 自拍 另类 综合 欧美小说 | 极品尤物一区二区 | 玖玖精品国产 | 久久久久久黄 | 国产日韩欧美二区 | 成人免费在线观看 | 欧美成人免费全部网站 | 操日本老妇 | 乡村美女户外勾搭av | 粗了大了 整进去好爽视频 色偷偷亚洲男人的天堂 | 国产精品一区不卡 | 被灌满精子的波多野结衣 | 亚洲中文字幕无码久久2017 | av人摸人人人澡人人超碰妓女 | 国产精品乱码一区二区三 | 可以看三级的网站 | 亚洲乱码国产乱码精品精网站 | 日韩视频一区二区三区在线播放免费观看 | 99蜜桃臀精品视频在线观看 | 久久特级毛片 | 99热这里只有精品4 99热这里只有精品5 | 国产成人亚洲综合a∨猫咪 国产成人亚洲综合a∨婷婷 | 久久婷婷五月综合色和啪 | 国产二区一区 | 午夜在线观看视频 | 亚洲国产精品无码久久电影 | 国产曰肥老太婆无遮挡 | 午夜黄色福利视频 | 亚洲精品少妇一区二区 | 日韩黄色一级 | 日本高清在线播放 | 99精品久久精品一区二区 | 无码日韩人妻精品久久蜜桃 | 午夜激情福利视频 | 欧美久久久久久 | 男人天堂视频在线 | 无码里番纯肉h在线网站 | 久久亚洲国产成人精品无码区 | jizz精品| 亚洲天堂五月天 | 欧美精品一级 | 日本美女交配 | 91青青操| 国产真实乱人偷精品 | 91字幕网 | 国产成人精品在线 | 少妇尝试黑人粗吊受不了 | 看91| 在线免费观看福利 | 日本少妇做爰奶水狂喷小说 | 少妇又紧又色又硬又爽 | 美女一区二区三区 | av资源一区 | 91大尺度| 国产免费一区 | 午夜影视免费 | 永久www成人看片 | 无码一区二区三区亚洲人妻 | 中文字幕亚洲一区二区va在线 | 国产精品白浆无码流出 | 亚洲国产日韩欧美在线观看 | 精品人伦一区二区三区 | 婷婷五月综合丁香在线 | 色噜噜狠狠狠狠色综合久不 | 688欧美人禽杂交狂配 | 国产综合影院 | 亚洲国产制服丝袜先锋 | 色峰视频 | 神马午夜场| 色中色成人导航 | 国产精品v日韩精品v在线观看 | 岛国一区二区 | 亚洲综合色一区 | 黄色一级片a | 超碰国产97 | 欧美日韩激情 | 国产黄a三级三级三级av在线看 | 9999国产精品欧美久久久久久 | 日本女优在线看 | 日本爽快片100色毛片 | 九一亚洲精品 | 久草这里只有精品 | 国产精品suv一区二区三区 | 国产婷婷精品 | 国产无遮挡又黄又爽对白视频 | 182tv在线观看免费午夜免费线路 | 一级黄色a视频 | 日本ts人妖系列在线专区 | 久久大胆视频 | 97精品国产 | 欧美另类性| 午夜精品一区二区三区三上悠亚 | 精品999视频 | 久久久无码精品一区二区三区蜜桃 | 婷婷色婷婷开心五月四房播播 |