本文選題：冷彎薄壁型鋼 + 穩(wěn)定性能　； 參考：《沈陽(yáng)建筑大學(xué)》2014年碩士論文

【摘要】：冷彎薄壁型鋼構(gòu)件的穩(wěn)定問(wèn)題一直是鋼結(jié)構(gòu)科研工作者和規(guī)范編制人員工作中的重點(diǎn)。新型截面形式的出現(xiàn)以及超薄、高強(qiáng)鋼材的應(yīng)用,帶來(lái)了許多新的穩(wěn)定問(wèn)題。目前,對(duì)冷彎薄壁型鋼受壓構(gòu)件的穩(wěn)定問(wèn)題的研究和成果大多集中在截面形式簡(jiǎn)單的槽鋼和卷邊槽鋼類構(gòu)件,對(duì)于設(shè)置加勁肋和復(fù)雜卷邊等復(fù)雜截面形式的研究成果相對(duì)較少�，F(xiàn)有的關(guān)于復(fù)雜截面形式的研究大都是針對(duì)軸心受壓構(gòu)件,對(duì)于偏心受壓構(gòu)件的研究還很少見(jiàn)。另外,現(xiàn)有的有效截面計(jì)算方法已經(jīng)不足以滿足各種新型截面形式構(gòu)件的計(jì)算。因此,國(guó)外學(xué)者提出直接強(qiáng)度計(jì)算方法來(lái)代替有效截面法計(jì)算冷彎薄壁型鋼構(gòu)件的承載力。目前,各國(guó)規(guī)范中采用的直接強(qiáng)度計(jì)算方法只適用于計(jì)算軸壓狀態(tài)或純彎狀態(tài)下的槽鋼和卷邊槽鋼構(gòu)件,關(guān)于偏壓狀態(tài)下的槽鋼和卷邊槽鋼構(gòu)件的直接強(qiáng)度計(jì)算方法還沒(méi)有明確的計(jì)算公式。針對(duì)這些問(wèn)題,本文分別對(duì)復(fù)雜卷邊槽鋼、腹板中間∑形加勁復(fù)雜卷邊槽鋼、腹板中間V形加勁復(fù)雜卷邊槽鋼三種截面形式,共計(jì)12根簡(jiǎn)支偏心受壓構(gòu)件進(jìn)行了承載力試驗(yàn)。研究了構(gòu)件的極限承載力、破壞模式及變形等特性。試驗(yàn)結(jié)果表明,腹板加勁有效地減小了板件寬厚比,大幅度提高向腹板一側(cè)偏心受壓構(gòu)件的極限承載力,使畸變屈曲代替局部屈曲起主要控制作用,但對(duì)向卷邊一側(cè)偏心受壓構(gòu)件的極限承載力影響很小采用非線性有限元軟件ANSYS對(duì)試驗(yàn)進(jìn)行了有限元模擬,驗(yàn)證了模擬的有效性。在此基礎(chǔ)上,對(duì)3種不同截面形式共計(jì)302個(gè)算例的復(fù)雜卷邊槽鋼偏心受壓構(gòu)件穩(wěn)定性能進(jìn)行了模擬分析。結(jié)果表明：腹板加勁可以提高向腹板一側(cè)偏心受壓構(gòu)件的極限承載力和鋼材利用率,其中∑形加勁要優(yōu)于V形加勁。有效形心偏移對(duì)偏壓構(gòu)件承載力的影響不可忽視,構(gòu)件極限承載力最大值出現(xiàn)在荷載作用于有效形心位置處時(shí)。板厚變化對(duì)腹板中間V形加勁復(fù)雜卷邊槽鋼影響顯著。以我國(guó)現(xiàn)有的偏心受壓構(gòu)件的有效截面計(jì)算方法為基礎(chǔ),結(jié)合軸心受壓構(gòu)件和純彎構(gòu)件的直接強(qiáng)度法,提出了偏心受壓構(gòu)件的直接強(qiáng)度計(jì)算方法。通過(guò)對(duì)125個(gè)構(gòu)件的已有試驗(yàn)和103個(gè)算例模擬結(jié)果進(jìn)行驗(yàn)算確定,本文提出公式適用于計(jì)算荷載作用在對(duì)稱軸平面內(nèi)的普通卷邊槽鋼和復(fù)雜卷邊槽鋼偏心受壓構(gòu)件的承載力。
[Abstract]:The stability of cold-formed thin-walled steel members has always been the focus of scientific research workers and code compilers of steel structures. The appearance of new cross-section and the application of super-thin and high-strength steel have brought many new stability problems. At present, most of the researches and achievements on the stability of cold-formed thin-walled steel compression members are focused on channel steel and crimped channel steel members with simple section form, but the research results on the complicated section form such as stiffening rib and complicated edge are relatively few. Most of the existing researches on complex cross-section are aimed at axial compression members, but the research on eccentric compression members is rare. In addition, the existing effective section calculation methods are not enough to meet the calculation of various new cross-section members. Therefore, foreign scholars put forward direct strength calculation method instead of effective section method to calculate the bearing capacity of cold-formed thin-walled steel members. At present, the direct strength calculation methods used in national codes are only suitable for calculating channel steel and crimped channel steel members under axial compression or pure bending. There is no clear formula for calculating the direct strength of channel steel and crimped channel steel members under the state of bias. Aiming at these problems, the bearing capacity of 12 simply supported eccentrically compressed members were tested in this paper, including complex crimped channel steel, sigma-shaped stiffened channel steel with complex edge, and V-shaped stiffened and complicated crimped channel steel with V-shape in the middle of web plate. The ultimate bearing capacity, failure mode and deformation of the members are studied. The test results show that the stiffening of web can effectively reduce the width to thickness ratio of the plate, greatly increase the ultimate bearing capacity of eccentric compression members on one side of the web, and make the distortion buckling play a major role in controlling the local buckling instead of the local buckling. But the ultimate bearing capacity of eccentric compression members on one side of the crimping edge is very small. The nonlinear finite element software ANSYS is used to simulate the finite element test, and the validity of the simulation is verified. On the basis of this, the stability performance of eccentric compression members of complicated crimped channel steel with 302 different cross section forms is simulated and analyzed. The results show that the ultimate bearing capacity and steel utilization ratio of eccentric compression members on one side of the web can be improved by stiffening the web, in which 鈭，

本文編號(hào)：1877559