【摘要】：復(fù)合材料加筋壁板結(jié)構(gòu)是航空航天復(fù)合材料結(jié)構(gòu)中應(yīng)用非常廣泛的一種典型結(jié)構(gòu),其中筋條和蒙皮的脫粘是主要的損傷形式。Z-pin增強(qiáng)技術(shù)作為一種適用于預(yù)浸料成形復(fù)合材料的層間增強(qiáng)技術(shù),可用于加筋壁板結(jié)構(gòu)連接界面的增強(qiáng)。本文在Z-pin增強(qiáng)T型加筋結(jié)構(gòu)制備工藝試驗(yàn)的基礎(chǔ)上,針對(duì)復(fù)合材料T型加筋結(jié)構(gòu)的界面連接性能,開(kāi)展試驗(yàn)研究和數(shù)值分析,研究參數(shù)對(duì)結(jié)構(gòu)承載力的影響規(guī)律及Z-pin增強(qiáng)機(jī)理,為Z-pin在復(fù)合材料加筋結(jié)構(gòu)增強(qiáng)中的實(shí)際應(yīng)用提供指導(dǎo)及參考。(1)研究Z-pin增強(qiáng)T型加筋結(jié)構(gòu)試樣的成型工藝,并對(duì)工藝進(jìn)行改進(jìn)。設(shè)計(jì)制作專(zhuān)用成型模具,進(jìn)行熱壓罐固化成型。結(jié)果表明,利用增加模具突緣厚度、增大筋條拐角半徑、增加拐角區(qū)的填充量等方法,可以解決Z-pin不能完全穿透預(yù)浸料坯料、填充區(qū)不密實(shí)等問(wèn)題,有效改善試件的成型質(zhì)量。(2)通過(guò)面外拉伸試驗(yàn)和剪切試驗(yàn)表征T型加筋結(jié)構(gòu)筋條-蒙皮間的連接性能,并研究Z-pin對(duì)加筋結(jié)構(gòu)的增強(qiáng)機(jī)理。研究表明,Z-pin對(duì)T型加筋結(jié)構(gòu)的初始載荷沒(méi)有影響,但能提高極限載荷及殘余載荷;隨著加載過(guò)程,Z-pin受力狀況由純I型方向?qū)娱g應(yīng)力逐漸轉(zhuǎn)變?yōu)镮/II型方向混合應(yīng)力,導(dǎo)致Z-pin發(fā)生側(cè)向擠壓,這一過(guò)程對(duì)Z-pin的增強(qiáng)效果有強(qiáng)化作用。剪切試驗(yàn)發(fā)現(xiàn),試樣筋條和蒙皮發(fā)生瞬間分離破壞,Z-pin明顯提高初始載荷,但對(duì)試樣掉載后殘余承載能力的作用不明顯。(3)研究Z-pin體積含量對(duì)T型加筋結(jié)構(gòu)拉伸承載力的影響規(guī)律,在此基礎(chǔ)上研究Z-pin對(duì)含損傷T型加筋結(jié)構(gòu)的增強(qiáng)作用,并進(jìn)一步研究突緣長(zhǎng)度對(duì)Z-pin增強(qiáng)效果的影響。Z-pin含量對(duì)比試驗(yàn)結(jié)果表明,T型加筋結(jié)構(gòu)拉伸承載力隨Z-pin含量增加而先上升后下降,Z-pin可使極限載荷的提高高達(dá)70.4%。預(yù)制缺陷試驗(yàn)結(jié)果表明,對(duì)于T型接頭中占粘結(jié)面10%~30%尺度的層間缺陷,Z-pin橋聯(lián)作用能實(shí)現(xiàn)對(duì)結(jié)構(gòu)承載能力較大程度的保持,將相同尺度缺陷空白T型接頭的極限載荷提高90%以上。突緣試驗(yàn)結(jié)果表明,試樣的失效形式隨突緣長(zhǎng)度增加發(fā)生轉(zhuǎn)變;Z-pin植入后,T型接頭的最優(yōu)突緣長(zhǎng)度由60mm降低為40mm,對(duì)結(jié)構(gòu)減重有重要意義。(4)借助估算法確定界面剛度和強(qiáng)度的取值,并利用能量差值平均化方法對(duì)現(xiàn)有的Z-pin增強(qiáng)等效方法進(jìn)行改進(jìn),采用分區(qū)內(nèi)聚力模型建立Z-pin增強(qiáng)T型加筋結(jié)構(gòu)的二維數(shù)值模型。以此為基礎(chǔ),利用該模型對(duì)不同約束跨距、蒙皮厚度的T型加筋結(jié)構(gòu)拉伸承載力進(jìn)行分析。結(jié)果表明,在試驗(yàn)范圍內(nèi),隨著跨距增大或蒙皮厚度減小,筋條-蒙皮連接界面拉剪應(yīng)力比值減小,Z-pin由拔脫失效轉(zhuǎn)變?yōu)榘蚊?斷裂混合失效,Z-pin增強(qiáng)T型接頭的拉伸承載力下降。
[Abstract]:Composite stiffened panel structure is a typical structure widely used in aerospace composite structure. The debonding of tendons and skin is the main damage form. Z-pin reinforcement is a kind of interlaminar strengthening technology suitable for prepreg forming composite materials. It can be used to strengthen the interface of stiffened panels. In this paper, based on the experimental results of Z-pin reinforced T-reinforced structures, the experimental study and numerical analysis are carried out to study the influence of parameters on the bearing capacity of T-reinforced composite structures and the mechanism of Z-pin reinforcement, aiming at the interfacial bonding properties of T-reinforced composite structures. It provides guidance and reference for the practical application of Z-pin in reinforced composite structure. (1) the forming process of Z-pin reinforced T-reinforced structure specimen is studied and the process is improved. Design and manufacture special moulds to solidify the hot-pressed tank. The results show that by increasing the thickness of the die edge, increasing the corner radius of the bar and increasing the filling amount of the corner area, the problems of Z-pin can not penetrate the blank of prepreg completely and the filling area is not dense, etc. (2) the tensile test and shear test were used to characterize the bonding properties of T-type reinforced structure between the stiffened strip and the skin, and the reinforcement mechanism of the reinforced structure by Z-pin was studied. The results show that Z-pin has no effect on the initial load of T-type reinforced structure, but it can increase the limit load and residual load, and with the process of loading, the interlaminar stress in the direction of pure I-type is gradually changed to the mixed stress in the direction of I/II. The lateral extrusion of Z-pin results in the enhancement of Z-pin by this process. The results of shear test show that the breaking of the strip and the skin increases the initial load obviously, but the effect on the residual bearing capacity of the specimen is not obvious. (3) the effect of the volume content of Z-pin on the tensile capacity of T-reinforced structure is studied. On this basis, the enhancement effect of Z-pin on T-stiffened structures with damage was studied. Furthermore, the effect of edge length on the strength of Z-pin was studied. The results showed that the tensile capacity of T-type reinforced structure increased first and then decreased with the increase of Z-pin content, and the ultimate load increased as high as 70.4%. The experimental results of prefabricated defects show that for T-joints with 10% or 30% of bonding surface, Z-pin bridging can maintain the bearing capacity of the structure to a large extent, and increase the limit load of blank T-joints with the same size defects by more than 90%. The results of edge test show that the failure form of the specimen changes with the length of the edge. The optimum edge length of T-joint is reduced from 60mm to 40mm after Z-pin implantation. (4) the value of interface stiffness and strength is determined by means of estimating method. The energy difference averaging method is used to improve the existing Z-pin enhancement equivalent method, and the two-dimensional numerical model of Z-pin reinforced T-stiffened structure is established by using the zone cohesion model. Based on this model, the tensile capacity of T-type reinforced structures with different restrained span and skin thickness is analyzed. The results show that in the range of test, with the increase of span or the decrease of skin thickness, the ratio of tensile shear stress at the interface of stiffened strip and skin decreases from pull-out failure to mixed pull-out / fracture failure. The tensile strength of T-joint reinforced by Z-pin decreases.
【學(xué)位授予單位】：南京航空航天大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TB33

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李夢(mèng)佳;陳普會(huì);孔斌;彭濤;姚正蘭;邱學(xué)仕;;縫合參數(shù)對(duì)復(fù)合材料T型接頭拉脫承載能力的影響[J];復(fù)合材料學(xué)報(bào);2016年03期

2 吳海;肖加余;邢素麗;文思維;楊孚標(biāo);楊金水;;含誘導(dǎo)缺陷復(fù)合材料T型接頭的彎曲失效實(shí)驗(yàn)[J];國(guó)防科技大學(xué)學(xué)報(bào);2015年04期

3 馬玉娥;杜永華;許盼福;;基于黏聚區(qū)模型的Z-pin增強(qiáng)復(fù)合材料T型接頭分層損傷研究[J];西北工業(yè)大學(xué)學(xué)報(bào);2015年03期

4 姜曉偉;朱書(shū)華;李國(guó)弘;徐建;童明波;;含分層缺陷復(fù)合材料層合板分層擴(kuò)展研究[J];航空計(jì)算技術(shù);2014年05期

5 鄭錫濤;羅貴;李宇徒;;復(fù)合材料層間性能改善方法研究進(jìn)展[J];航空制造技術(shù);2013年15期

6 盛儀;熊克;卞侃;熊璇;陳宏;郝銀鳳;;拉伸狀態(tài)下碳纖維復(fù)合材料T型接頭的斷裂行為[J];復(fù)合材料學(xué)報(bào);2013年06期

7 張向陽(yáng);李勇;褚奇奕;肖軍;董曉陽(yáng);;Z-pin點(diǎn)陣分布對(duì)層合板面內(nèi)壓縮性能的影響[J];航空學(xué)報(bào);2014年01期

8 孫晶晶;張曉晶;宮占峰;汪海;;復(fù)合材料帽型筋條脫粘的失效機(jī)理分析[J];航空學(xué)報(bào);2013年07期

9 許巍;陳力;張錢(qián)城;楊金水;魏悅廣;盧天健;;粘結(jié)界面力學(xué)行為及其表征[J];中國(guó)科學(xué):技術(shù)科學(xué);2012年12期

10 徐建;印春偉;童明波;;復(fù)合材料T型加筋結(jié)構(gòu)連接界面性能研究[J];江蘇航空;2012年S1期

相關(guān)會(huì)議論文 前2條

1 王雪明;謝富原;李敏;王菲;張佐光;;熱壓罐成型復(fù)合材料構(gòu)件分層缺陷影響因素分析[A];第十五屆全國(guó)復(fù)合材料學(xué)術(shù)會(huì)議論文集（上冊(cè)）[C];2008年

2 謝佳卉;魏宏艷;周建鋒;楊勝春;沈真;;面外拉伸載荷作用下含缺陷T型結(jié)構(gòu)失效分析[A];第十五屆全國(guó)復(fù)合材料學(xué)術(shù)會(huì)議論文集（下冊(cè)）[C];2008年

相關(guān)博士學(xué)位論文 前2條

1 張璐;含分層缺陷復(fù)合材料層合板分層擴(kuò)展行為與數(shù)值模擬研究[D];哈爾濱工業(yè)大學(xué);2012年

2 葉強(qiáng);層合復(fù)合材料的粘聚區(qū)模型及其應(yīng)用研究[D];南京航空航天大學(xué);2012年

相關(guān)碩士學(xué)位論文 前1條

1 韓闖;復(fù)合材料T型接頭拉脫性能研究[D];哈爾濱工業(yè)大學(xué);2013年

，

本文編號(hào)：2231974