本文選題：地錨斜拉橋 + 獨(dú)塔半地錨PC斜拉橋��； 參考：《長(zhǎng)安大學(xué)》2017年博士論文

【摘要】：本文針對(duì)獨(dú)塔地錨預(yù)應(yīng)力混凝土(PC)斜拉橋,以得到其適宜選取的體系及結(jié)構(gòu)參數(shù)范圍為目的展開了研究。介紹了研究對(duì)象的結(jié)構(gòu)形式,論述了地形條件、施工工藝及主梁力學(xué)平衡機(jī)理,確定了適宜選取的體系。在此基礎(chǔ)上建立了以安全要求為基礎(chǔ)綜合考慮經(jīng)濟(jì)性能及美觀要求的結(jié)構(gòu)性能評(píng)價(jià)體系,并據(jù)此展開了對(duì)獨(dú)塔地錨PC斜拉橋關(guān)鍵結(jié)構(gòu)參數(shù)合理范圍的研究。所做的主要工作及主要成果包括:(1)通過對(duì)工程實(shí)例的調(diào)研,總結(jié)獨(dú)塔地錨PC斜拉橋適應(yīng)的地形條件為高低起伏的山區(qū)峽谷地形,適應(yīng)的施工工藝為主跨懸臂澆筑施工,邊跨懸臂澆筑或支架施工。(2)對(duì)不同斜拉橋體系進(jìn)行恒活載內(nèi)力計(jì)算,研究其力學(xué)平衡機(jī)理。結(jié)果表明:與常規(guī)斜拉橋相比,獨(dú)塔地錨PC斜拉橋不對(duì)稱性較高,結(jié)構(gòu)受力特點(diǎn)為塔柱兩側(cè)拉索水平力差值較大,作用于主梁后需借助塔柱、承臺(tái)或錨碇傳遞至基礎(chǔ),且塔柱所受彎矩較大;獨(dú)塔半地錨PC斜拉橋的軸力平衡機(jī)理與跨中設(shè)伸縮鉸的雙塔半地錨斜拉橋相同,均需要錨碇所受的基底摩擦力及土側(cè)壓力平衡不對(duì)稱結(jié)構(gòu)極大的拉索水平力差值;但是,同為半地錨斜拉橋,雙塔三跨錨碇與主梁分離的體系與獨(dú)塔體系軸向受力截然不同,前者主跨塔梁結(jié)合處壓力轉(zhuǎn)化為跨中拉力,其所具備的減小塔梁交接處軸力以增大主跨跨度的優(yōu)點(diǎn)并不適用于后者;獨(dú)塔半地錨PC斜拉橋宜采用支撐體系,邊跨主梁與錨碇宜固結(jié);獨(dú)塔全地錨PC斜拉橋宜采用固結(jié)體系且無下塔柱或采用截面面積較大的下塔柱。(3)論證了結(jié)構(gòu)設(shè)計(jì)的造型適應(yīng)性,提出了中小跨徑獨(dú)塔斜拉橋設(shè)計(jì)計(jì)算時(shí)需要考慮拉索承擔(dān)的恒活載比例的觀點(diǎn),推導(dǎo)了體現(xiàn)結(jié)構(gòu)整體剛度的活載作用下塔頂偏位及主跨最大撓度計(jì)算公式,構(gòu)建了體現(xiàn)結(jié)構(gòu)經(jīng)濟(jì)性的總造價(jià)及單位橋長(zhǎng)造價(jià)估算方法,形成了以安全要求為基礎(chǔ)綜合考慮經(jīng)濟(jì)性能及造型需求的結(jié)構(gòu)性能評(píng)價(jià)體系,為后續(xù)研究解決了研究方法問題。(4)以結(jié)構(gòu)性能評(píng)價(jià)體系對(duì)獨(dú)塔半地錨PC斜拉橋進(jìn)行了研究,選定了邊主跨比、錨碇邊跨長(zhǎng)度比、主跨邊索傾角為關(guān)鍵結(jié)構(gòu)參數(shù),提出:(1)邊主跨比的合理取值范圍在0.25~0.50左右,跨度越大、錨固單價(jià)(錨碇錨桿承擔(dān)荷載比)越高取值越大;當(dāng)受地形條件限制僅考慮主跨跨越能力而邊主跨比較小時(shí),應(yīng)適當(dāng)降低主跨邊索傾角增大地錨背索索距;當(dāng)?shù)匦伍_闊考慮全橋跨越能力時(shí),邊主跨比宜取大值,且宜選擇較大主跨邊索傾角及較小錨碇邊跨長(zhǎng)度比;(2)當(dāng)?shù)匦螚l件適宜采用獨(dú)塔半地錨PC斜拉橋時(shí),錨碇邊跨長(zhǎng)度比越大經(jīng)濟(jì)性能越高;(3)合理主跨邊索傾角的取值在22.0°左右。研究表明了獨(dú)塔半地錨PC斜拉橋在受地形條件限制僅考慮主跨跨越能力而邊主跨比較小時(shí)經(jīng)濟(jì)性能優(yōu)于常規(guī)斜拉橋。(5)以結(jié)構(gòu)性能評(píng)價(jià)體系對(duì)獨(dú)塔全地錨PC斜拉橋進(jìn)行了研究,選定了塔柱傾角、地錨背索傾角、主跨邊索傾角為關(guān)鍵結(jié)構(gòu)參數(shù),提出:(1)塔柱傾角的合理取值范圍在65°~85°左右,且需滿足最小塔柱傾角的要求;跨度越大、主跨邊索傾角越大經(jīng)濟(jì)塔柱傾角取值越大,地錨背索傾角越大、錨固單價(jià)(錨碇錨桿承擔(dān)荷載比)越大經(jīng)濟(jì)塔柱傾角取值越小;當(dāng)?shù)劐^背索傾角取值合理時(shí),經(jīng)濟(jì)塔柱傾角均大于根據(jù)受力及造型要求得到的最小塔柱傾角;(2)合理地錨背索傾角的取值在60°左右,在50°~70°之間;(3)合理主跨邊索傾角的取值在22.5°左右,20.5°~25.0°之間,跨度越大、錨固單價(jià)越高取值越大。(6)分別對(duì)獨(dú)塔半地錨及全地錨PC斜拉橋進(jìn)行了試設(shè)計(jì),并以此驗(yàn)證了活載作用下塔頂水平偏位、主跨最大撓度及材料用量的計(jì)算公式。
[Abstract]:In this paper, a single tower anchorage prestressed concrete (PC) cable-stayed bridge is studied in order to obtain the suitable selection system and the range of structural parameters. The structure form of the research object is introduced, the terrain conditions, the construction technology and the mechanism of the balance of the main beam mechanics are discussed, and the suitable selection system is determined. On this basis, the safety of the system is established. The structural performance evaluation system based on the comprehensive consideration of economic performance and aesthetic requirements is required, and the rational range of key structural parameters of the single tower anchor PC cable-stayed bridge is studied. The main work and main achievements are as follows: (1) through the investigation of the engineering examples, the topographic conditions of the Single Tower Anchorage PC cable-stayed bridge are summarized. Low undulating mountain canyon terrain, the suitable construction technology is mainly span cantilever pouring construction, Side Span Cantilever placement or scaffold construction. (2) calculation of constant live load of different cable-stayed bridge system, and study its mechanical balance mechanism. The results show that compared with conventional cable-stayed bridge, the Single Tower Anchorage PC cable-stayed bridge has higher asymmetry and structural stress characteristics The horizontal force difference between the two sides of the column is larger. After the effect on the main beam, the tower column, the bearing platform or the anchorage should be transferred to the foundation, and the bending moment of the column is larger. The axial force balance mechanism of the single tower and half anchor PC cable-stayed bridge is the same as that of the Twin Towers half anchorage bridge spanning the telescopic hinge in the middle of the bridge, all need the base friction and the earth pressure balance under the anchorage. The difference between the symmetrical structure and the horizontal force of the cable is great. However, the same as the half anchored cable-stayed bridge, the system of the three span anchorage of the Twin Towers is completely different from the single tower system, and the former is transformed into a mid span tensile force, and the advantages of reducing the axial force at the junction of the tower beam to increase the span of the main span are not applicable to the length of the main span. The latter, the single tower and half anchor PC cable-stayed bridge should adopt the support system, the side span of the main beam and the anchorage should be consolidated; the single tower full anchor PC cable-stayed bridge should adopt the consolidation system, without the lower column or the larger section of the lower section. (3) the adaptability of the structural design is demonstrated, and the design and calculation of the small span single tower cable-stayed bridge should be taken into consideration. In the view of the constant live load ratio, the calculation formula of the top deflection and the maximum deflection of the main span under the active load of the structure is derived, and the total cost of the structure economy and the cost estimation method of the unit bridge length are constructed, and the structural performance of the economic performance and the modeling demand is formed on the basis of the safety requirements. The evaluation system has solved the problem of research methods for the follow-up research. (4) study the single tower and half anchor PC cable-stayed bridge with the structural performance evaluation system, selected the side main span ratio, the span length ratio of the anchorage and the main span cable inclination angle as the key structural parameters, and put forward that the reasonable range of the main span ratio of (1) side is around, the greater the span, the larger the span, the anchorage single. The higher the value is, the higher the value is, the higher the value of the anchorage is bearing the load ratio; when the terrain conditions are limited to consider the span span of the main span and the side main span is relatively small, the anchor back cable distance should be appropriately reduced by the main span of the main span cable. When the terrain is open and the full bridge span capacity is considered, the side main span ratio should be taken large value, and the larger main span cable angle and the smaller angle should be selected. The span length ratio of the anchorage side; (2) when the topographic condition is suitable to adopt the single tower and half anchor PC cable-stayed bridge, the greater the economic performance of the span length ratio, and (3) the reasonable main span cable inclination angle is about 22 degrees. The study shows that the single tower and half anchorage cable stayed bridge is limited to the main span span and the side main span is relatively small on the terrain condition. The economic performance is better than the conventional cable-stayed bridge. (5) the single tower full anchor PC cable-stayed bridge is studied with the structural performance evaluation system. The column tilt angle, the ground anchorage angle and the main cross side cable inclination are the key structural parameters. (1) the reasonable range of the angle of the tower column is about 65 ~85 degrees, and the requirement of the minimum column inclination is met; the span is more than the span. The greater the angle of the economic tower, the greater the inclination angle of the economic tower, the greater the inclination angle of the economic tower, the greater the inclination angle of the anchor back cable, the smaller the inclination of the economic tower of the anchorage (anchorage anchor load ratio); the inclination of the economic tower column is greater than that of the minimum column angle according to the force and the requirement of the shape. (2) the reasonable anchor back. The value of the cable inclination is about 60 degrees, between 50 degrees ~70 degrees, and (3) the value of the reasonable main cross side cable inclination is about 22.5 degrees, 20.5 degrees ~25.0 degrees, the greater the span and the higher the value of the anchorage unit price. (6) the single tower and half anchor and the full anchor PC cable-stayed bridge are designed respectively, and the horizontal deviation of the top of the tower under the action of live load is verified, and the main span is the most main span. The formula for calculating the large deflection and the amount of material.

【學(xué)位授予單位】：長(zhǎng)安大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2017
【分類號(hào)】：U448.27
，

本文編號(hào)：1877422