法向拉應力 的英文怎麼說
中文拼音 [fǎxiànglāyīnglì]
法向拉應力
英文
direct tensil stress-
The dynamic tensile stresses of earthquake may balance or exceed to the precompression stresses due to static watef, this may arouse opening of joints along the normal direction. if the altemate actions of earthquake join, the joints may behave gradual opening and closing
由於地震作用時的動拉應力將抵消並超過靜載作用下的壓應力,導致橫縫面沿法向張開,加上地震的交變作用,橫縫可能會呈現反復的「漸開漸合」現象。The welding technology of francis turbine runners is optimized from the view of subsection welding and local heating by numerical simulation. the result shows that welding residual tensile stress appears in the weld and its area nearby, and peak stress appears in the dangerous area of blades after practising quondam welding technology ; welding residual tensile peak stress in the dangerous area of blades can be decreased by welding both ends earlier and then welding middle section later during subsection welding, and decreasing effect on welding residual stress of the subsection welding is related to the weld length of blade outlets and welding direction of each subsection ; decreasing effect on residual stress of the local heating is direct proportional to heating time, heating temperature, heating area, and inversely proportional to cooling area, and welding residual tensile peak stress in the dangerous area is decreasing trend earlier, and then increasing trend later with heated location increased
本文利用數值模擬手段對轉輪的焊接工藝從分段焊和局部加熱兩個方面進行了優化,結果表明:採用普通工藝焊接時,葉片焊后殘余拉應力出現在焊縫及其附近區域,並且在葉片出水邊的熔合線附近(危險區域)出現了峰值;在採用優化的分段焊時,先焊兩端后焊中間的方法可以降低葉片危險區域的焊接殘余拉應力峰值,降低效果與葉片出水邊焊段長度、焊縫各段的焊接方向有關;局部加熱法降低轉輪危險區域殘余應力的效果主要與加熱時間、加熱溫度以及加熱面積成正比,與冷卻面積成反比,並且危險區域的殘余應力隨加熱區域的增大呈先降低后升高的趨勢。Based upon virtual displacement method and the updated - lagrangian approach, stiffness matrices for two - dimensional elastic - plastic beam model in large displacement were proposed, in the derivation of which transverse stress was included because it was believed that part of the 2nd order effects of various stresses, which are in equilibrium with each other and with the external loads, will counteract each other and neglecting either part would possibly lead to incorrect results
利用虛位移原理和更新的拉格朗日方法,導出了大位移彈塑性梁單元剛度矩陣的顯式表達式,在剛度矩陣推導中引入了截面內非線性剪應力和橫向應力的影響,剛度矩陣通過了剛體檢驗。之所以要引入橫向應力的影響,是因為本文認為,保持平衡所需的所有應力,它們各自的二階效應會相互抵消,因此忽略其中的任何一項都可能導致不正確的結果。It is determined that with accurate knowledge of the complete stress - strain curve of concrete in compression, steel in tension, and with an iterative computerized non ? linear method, it is possible to predict the entire moment - curvature, moment - flexural rigidity and axial rigidity relation ship of a cross - section of a structure member
可以確定,只要知道混凝土受壓和鋼筋受拉的完整的應力應變關系,採用選代的非線性計算方法,就有可能預測結構截面彎矩一曲率、彎矩一彎曲剛度和軸向剛度的關系。This paper focuses on the research of the stress mechanism of the ribbed shell structure in statics, dynamics and under the explosive load on the basis of the engineering practice of cave depot of single aircraft. in this paper, according to the classical shell theories, the basic differential equilibrium of the ribbed shell structure and the finite element analysis of 3d rippled plate are established, in which the function of annular ribs reinforcement bars and 3d ripped steel plates are distributed in the range of the steel, and the functions along the longitude direction of tension, bending, and torsion are neglected ; applied with dynamic analytical theory, the dynamic model of ribbed shell structure and the analytical theory model of elastic - plastic are set up ; the triangle series method is used to solve the displacement and stress under the distributed load and the concentrated load of the ribbed shell structure
本文以軍用機場地面單機掩蔽庫工程建設為工程背景,首次對內襯三維波紋鋼板混凝土拱型復合結構的受力機理進行了靜力、動力和爆炸荷載的分析研究。根據將橫肋、鋼筋及三維波紋鋼板的作用均勻分佈在殼體范圍內的情況,忽略橫肋、鋼筋及三維波紋鋼板沿殼體母線方向的抗拉、抗彎及其抗扭作用,首次推導出了內襯三維波紋鋼板混凝土殼體的微分平衡方程,建立了有限元計算模型,並採用三角函數法,求解了三維波紋鋼板混凝土拱型復合結構在分佈荷載和集中荷載作用下的位移響應和應力響應,並與普通殼體進行了比較。The contents include : based on the previous research and the data of experimentations, the author researches and develops a kind of satisfactory semi - empirical formula of nonlinear temperature distribution, and calculates the temperature stress of rigid - framed arch bridge by the fem. the temperature effects of bridge structure by annual and sunlight temperature difference are discussed, it indicates that the temperature effect of annual temperature difference is small but the temperature effect of sunlight temperature difference is great and the temperature stress along beam depth resulted from sunlight temperature difference is nonlinear. with the comparison between the temperature effects of different position of bridge, the results show that where the section of bridge is small, the temperature stress of it is large
本文主要包括以下內容:從理論上研究並結合實測資料發展了一種比較理想的半經驗溫度場非線性分佈公式,並將有限元方法應用於剛架拱橋結構溫度應力的計算中,對橋梁結構進行整體溫度應力分析;討論了年溫差和日照溫差引起的橋梁結構的溫度效應,表明年溫差引起的溫度效應較小,而日照溫差引起的溫度應力較大且沿梁高呈非線性分佈;分析比較了橋梁結構各個部位的溫度效應的大小,可知截面越小溫度拉應力越大,受力越不利;並對箱梁結構由於構造不同引起的縱向與橫向的溫度效應大小進行了探討,發現在頂板下緣也會出現相當大的溫度拉應力,並且梗腋的存在反而增加了頂板底部的溫度拉應力;還對幾種相近的剛構式橋型的溫度效應進行了分析對比,總結了這些橋型針對溫度效應的優劣,並提出相應的針對性措施。According to the documentation collected from domestic and abroad wang wei dong who works in huadong architect and structure institute utilizes the similar work property between the underground continuous wall and pile subjected the vertical loads, and introduces poulos method of elasticity and plastic which applies to pile foundation into the calculation for subsidence of underground continuous wall. pujialiu and yu yuzhou from water and electronic engineering of qinghua university, according to the result of three axes, define the concrete parameter utilize the model of non - linear e - b combined with the design cross section of dam in xiaolangdi, yellow river accept the total stress programme of thepd dam, and we analyze the stress and displacement of plastic concrete diaphragm wall by finite element method in comparison with the result of common concrete one. at same time, we consider the effect of the character of plastic concrete diaphragm wall which is composed of different gradients and adopting the level of stress and pulling stress infers whether the plastic concrete diaphragm wall is safe or not
地下連續墻是一種歷史較短的施工方法,目前,砼防滲墻的設計還是以傳統的設計方法為主,根據查找國內外文獻資料,華東建築設計院王衛東利用地下連續墻與樁在豎向荷載作用下的工作性能有相似性,將適用於樁基的poulos彈性理論引入對地下連續墻的沉降計算中;清華大學水利水電工程系濮家騮、于玉貞根據三軸試驗結果確定混凝土的參數,利用非線性e - b模型,結合黃河小浪底土石壩設計剖面,採用thepd土石壩總應力程序,對深覆蓋層塑性混凝土防滲墻的應力、位移進行有限元分析,並與普通混凝土防滲墻計算結果加以對比,同時分析了不同配比塑性混凝土特性的影響,並採用應力水平和拉應力數值來判斷塑性混凝土防滲墻的安全程度。2. a new design and construction method different from the traditional way was used in jinma bridge. when cantilever the main girder of the cable - stayed structure, the longitudinal pre - stressed reinforcements are not tensioned at once
2 、金馬大橋在斜拉橋設計和施工中採用一種與傳統斜拉橋設計和施工不同的新方法,即懸臂澆築斜拉橋主梁時採用無縱向預應力筋的做法。This new erection procedure is compared with the conventional way from the reasonability, convenience and economic aspects. the results obtained from the calculating data state that cantilevering the main girder without tensioning the longitudinal pre - stressed reinforcements is a better way for establishing the cable - stayed bridge
本文把這種方法與傳統方法在受力合理性、施工方便程度和經濟性方面做了比較分析,並結合整體靜力計算說明懸臂澆築斜拉橋主梁時不張拉縱向預應力筋這一方法的可取之處。According to the effective field expression which has been derived in former, the phenomenon that the tangential component of magnetic leakage field has maximum value and the normal component of magnetic leakage field acquires zero value at the stress concentration zone of positive magnetostriction ferromagnetism materials under the application of tensile stress and negative magnetostriction ferromagnetism materials under the application of compressive stress is explained theoretically through analyzing and discussing
根據所得到的地磁場中受力鐵磁性材料有效場表達式,通過分析討論,解釋了受拉力作用的正磁致伸縮鐵磁材料和受壓力作用的負磁致伸縮材料在應力集中處漏磁場切向分量出現最大值、同時法向分量為零值的現象。A bearing surface transmits the interaction between an arch dam and its foundation, the strength of which directly affects the constraint of the bedrock to the dam, and thus affects the stress and deformation of the dam. the influence is studied in this paper with nonlinear finite element method, as an example, for a high arch dam in design. the results show that the influence on stress is only limited within the local area near the bearing surface, larger on the maximum principal tensile stress than on the principal compression stress, and the decrease of the strength does not cause unlimited increase of the maximum stress. the influence on the displacement of the top of the dam is smaller than that of the bottom of the dam, especially the relative downstream displacement. at the lower strength of the bearing surface, the relative downstream displacement at the bottom of the dam increases with the decrease of the strength
建基面是傳遞拱壩和基巖相互作用的紐帶,它的強度直接影響基巖對壩體的約束,從而影響壩體的應力和變形.採用非線性有限單元法,以設計中的某高拱壩為例,分析建基面強度對壩體應力和變形的影響.結果表明建基面強度對壩體應力的影響僅限於建基面附近的局部范圍,對最大主拉應力的影響要大於對最大主壓應力的影響,建基面強度的降低不會無限地增大壩體的應力數值;建基面強度對壩頂位移的影響較小,但對壩底位移(尤其是順河向相對位移)的影響較大,當建基面強度較低時,壩底順河向相對位移隨建基面強度的降低而增大In order to reveal load mechanism and failure mode of thick pile caps, by means of the test of 1 / 4 - scale models of thick pile caps with six piles and post - handling study of 3 - dimensional non - linear finite element adina, this paper points out the shortage, which is that the design of pile caps is carried out by flexural strength in chinese technical code for building pile foundations jgj94 - 94 and american reinforcement concrete building construction code aci318 - 02, promulgates that the failure mode of thick pile caps is punching failure and load transfer mechanism is the strut - and - tie, which is that zones of concrete with primarily unidirectional compressive stresses are modeled by compress struts, while tension ties are used to model longitudinal reinforcement over pile
摘要為揭示厚承臺的傳力機理和破壞形式,通過對4個1 : 5比例的六樁厚承臺的模型試驗研究與三維非線性有限元adina的后處理研究,指出中國建築樁基技術規范jgj94 - 94與美國鋼筋砼房屋建築規范aci318 - 02規范中,承臺以彎曲強度進行配筋計算的設計方法之不足,揭示出厚承臺的破壞模式是沖切破壞,傳力機理是以帶有主要單向壓應力的砼區域作斜壓桿,樁頂區域的縱筋作拉桿的空間桁架。With the consideration of the vertical wave effect of soil and soil - pile interaction, an approximate analytical solution to vertical vibration of pile system with variable impedance in visco - elastic layered soil is developed. a simplified and practical mathematical model for interaction between soil layers is proposed, and its applicability is theoretically investigated. based on this model and by using laplace transforms and the transmit property of impedance function, the analytical expression of the impedance function and solutions of the displacement and velocity response function in frequency domain and in time domain at the pile head are derived
4 、從三維軸對稱土模型出發,對考慮樁土耦合作用、土層層間聯系以及樁周土豎向應力梯度變化條件下的成層粘彈性土中完整樁及變阻抗樁系統縱向振動問題進行了研究,提出了成層土中變阻抗樁系統縱向振動問題的近似解析解法和樁周土層層間相互作用的簡化而實用的數學模型,並利用拉氏變換和阻抗函數的傳遞性,獲得了成層土中任意段變阻抗樁樁頂阻抗函數的解析表達式,以及樁頂速度導納和時域速度響應解析解和半解析解。On the other hand, for the pre - press stress being threw by the hub was inserted after cooling with liquid nitrogen, the poor transverse tension strength of the multi - ring flywheel rotor could be counteracted. so the rotate speed and energy storage density can be increased efficiently
而採用多環套裝纏繞技術製造的多層飛輪輪環,在利用溫差過盈裝配方法給復合材料輪環施加預壓應力后,能夠有效避免飛輪轉子的復合材料輪環部分因較低的纖維橫向抗拉強度而破壞失效,從而大幅度提高飛輪轉子的極限轉速和儲能密度。Then, a step - by - step increase of vertical curvature is applied to the hull girder assuming that the plane cross section remains plane. at each incremental step, the stress of the cross section is evaluated using the average stress - strain curves of the elements as well as the incremental bending moment due to the curvature increment. performing sample calculations on existing girder models tests under pure bending, the rationality of the proposed method was examined
假設船體橫向框架材足夠強,因而板架的整體破壞不會發生;基於梁?柱理論、理想彈塑性假設、平面假設,建立了拉伸和壓縮加筋板單元的平均應力?應變關系曲線,應用船體結構總縱極限強度的簡化逐步破壞分析方法計算船體總縱極限彎矩,並據此開發了計算程序sus 。Bearing capacity and displacement are two main problems in the application of geotechnical engineering. based on a series of pull - out tests using three kinds of paper and a sort of window screening as geogrid, twenty - seven in limit and several in working - stress geogrid - reinforced slope model tests designed through orthogonal principle have been conducted to have obtained the relationship between the bearing capacity and four factors ( i. e. reinforcement, angle of reinforced slope, the designed - length of reinforcement and the distance between layers of reinforcement ). the law of slope lateral ( horizontal ) displacement versus to the height of slope vary with external - load was derived from the model test data, and the main factor affecting the lateral and vertical displacement of geogrid - reinforced slope was obtained through analysis
承載力(強度)和變形是巖土工程應用領域的兩大主要問題,本文以紙和窗紗布模擬加筋土邊坡的土工格柵,在一系列拉拔試驗的基礎上,以正交設計理論分別安排27個極限應力狀態和若干個工作應力狀態加筋土邊坡模型試驗,並以模型試驗獲得的數據為依據,採用誤差、極差及回歸分析方法,探討了加筋土邊坡承載力與筋類、筋長、層間距、坡角4因素的相關關系,獲得了在外荷載作用下加筋土邊坡的側向位移隨坡高的變化規律(並進行了定性解釋)和坡頂的豎向位移特性,並分析其主要控制因素。During the finite element modeling of the bridge, the factors affecting the accuracy of the finite element model are discussed in detail, such as, the geometrical non - linearity of the cable including gravitational sag and initial tension, and the structural orthotropic steel box - girder deck to be equivalent to physical orthotropic deck by using compound material mechanics, and so on
在建模過程中,盡可能多地考慮了一些影響全橋有限元模型精度的因素:如斜拉索的幾何非線性(重力垂度和初始應力) ,將構造正交各向異性鋼箱梁橋面板用復合材料力學的方法等效為物理正交各向異性板等。This thesis put forward a systemic method to settle the negative friction in project design. it includes when the negative friction must be consider, the zero position decided, count the down load, the negative friction group pile, the infection on end - bearing and sedimentation and stability, how to deal with in design to avoid the negative friction and how to solve when the negative friction produced
本文提出了在工程設計中如何處理樁基負摩擦力的方法,包括什麼情況下考慮負摩擦力、負摩擦力中性點位置的確定、樁基下拉荷載的計算、負摩擦力的群樁效應、負摩擦力對樁基豎向承載力和沉降的影響、設計施工中如何避免出現負摩擦力以及對已經出現的負摩擦力如何根治。Standard test method for machine direction elastic recovery and permanent deformation and stress retention of stretch wrap film
張拉材料加工方向彈性恢復和永久變形和應力保持標準試驗方法There are no calculation analysis methods for it and the design main depends on experience. the behind schedule theories research obstructs the csnw ' s further development. therefore, the thesis focuses on this topic and following foundamental studies on the relate issues are performed. on the soil nailing and composite research foundation, according to csnw ' s present research condition and the engineering effective demand, the stability of csnw is studied systematically by methods of theories research and case research
理論研究的落後制約了復合土釘墻支護的進一步發展,因此,在前人對土釘及復合土釘研究的基礎上,根據目前復合土釘墻支護的研究現狀和工程的實際需要,本文針對當前深基坑支護中廣泛應用的土釘墻及設計計算理論與設計方法,採用理論研究、工程實例相結合的方法,對土釘拉力和邊坡的側向土壓力進行了分析研究。分享友人