發(fā)布時間：2018-03-30 02:38

  本文選題：土木工程施工　切入點：模板支架　出處：《鄭州大學》2014年碩士論文

【摘要】：碗扣式鋼管腳手架由于其自身的優(yōu)點被廣泛地應用在市政橋梁工程中。由于碗扣式模架在設計及施工過程中理論依據(jù)不足及相關施工經(jīng)驗較少，并且其桿件多且整體受力規(guī)律復雜，稍有不慎就會造成模架坍塌，致使人員傷亡及財產(chǎn)損失。 目前，現(xiàn)有的碗扣式模板支架安全技術規(guī)范只是針對箱梁正下方模架的設計，對于翼緣下模架的搭設沒有提出設計標準，該部分搭設通常是根據(jù)經(jīng)驗搭設，無論從安全性還是經(jīng)濟性角度，都沒有定量的依據(jù)；另外，國內外的研究也主要是針對預壓期箱梁正下方模架受力性能的研究；而且縱觀腳手架現(xiàn)場事故，大部分是在混凝土澆筑過程發(fā)生的，因此，在混凝土澆筑期桿件受力性能的研究具有重要的意義。而論文以混凝土澆筑過程為前提進行的研究。 以鄭州市西三環(huán)-航海路立交工程中箱梁模板支架為試驗對象，通過現(xiàn)場內力監(jiān)測，研究混凝土澆筑過程中桿件內力分布和傳遞規(guī)律，并通過理論分析與現(xiàn)場實測值對比，探索模板支架立桿、斜撐和剪刀撐內力發(fā)展過程，總結模板支架搭設的技術要求。 研究得出以下主要結論： （1）混凝土澆筑過程中，，剛剛澆筑完成的斷面為危險斷面；施工斷面前后10m范圍內受混凝土澆筑影響較大，超出此起止范圍，混凝土澆筑對架體影響較小。 （2）一般立桿上部內力大于下部內力，建議工程實際中應減小支架立桿上部步距。 （3）翼緣下方的立桿，越靠近中軸線方向內力幅度越大，建議減小靠近中軸線的立桿的橫向間距。 （4）當混凝土澆筑速度過快時，支架中拉壓變號構件數(shù)量增多。建議工程實際中應控制混凝土的澆筑速度，且制定措施，保障均勻對稱澆筑。 （5）翼緣下方的剪刀撐以受拉為主，且下部拉力大于上部拉力；箱梁下方的剪刀撐，下部以受拉為主，上部以受壓為主。 （6）剪刀撐內力最大值達到16kN，超過雙排扣件理論抗滑強度，所以剪刀撐斜桿的接長處應采用特別挑選的優(yōu)質扣件，且不少于3個。 （7）翼緣下方的斜撐與模板的夾角應小于90°，且應上疏下密，與滿堂支架立桿的連接扣件應不少于3個。
[Abstract]:The bowl-button steel tube scaffolding has been widely used in municipal bridge engineering because of its own advantages, because of the lack of theoretical basis in the design and construction process and the lack of relevant construction experience, Moreover, it has many members and complex law of the whole force, which will cause the mould frame collapse and cause casualties and property losses. At present, the existing safety technical specifications of the bowl button-type formwork support are only for the design of the mould frame directly below the box girder, but there is no design standard for the construction of the die frame under the flange, which is usually based on the experience. There is no quantitative basis in terms of safety or economy; in addition, domestic and foreign studies are mainly aimed at the mechanical performance of the formwork under the box girder in preloading period. Most of them occur in the process of concrete pouring. Therefore, it is of great significance to study the mechanical properties of the members during the period of concrete pouring, and the research of this paper is based on the process of concrete pouring. Taking the box girder formwork support in the Xi San Huan-Haihe Road Interchange Project of Zhengzhou City as the test object, the distribution and transfer law of the internal force of the bar during the concrete pouring process are studied by monitoring the field internal force, and the theoretical analysis is compared with the field measured value. To explore the development process of internal force of formwork stand, diagonal brace and scissors brace, and summarize the technical requirements of formwork support erection. The main conclusions of the study are as follows:. 1) in the process of concrete pouring, the section that has just been poured is dangerous section, and the concrete pouring has a great influence on the frame body within 10m before and after construction, beyond which the concrete pouring has little influence on the frame body. 2) the upper internal force of the vertical rod is larger than the lower one. It is suggested that the upper step distance of the support rod should be reduced in engineering practice. The lower the flange, the greater the amplitude of internal force in the direction of the central axis. It is suggested that the transverse distance between the poles near the central axis be reduced. 4) when the pouring speed of concrete is too fast, the number of tension-compression variable number members in the support increases. It is suggested that the pouring speed of concrete should be controlled in engineering practice, and measures should be made to ensure uniform and symmetrical pouring. The lower part of the box girder is more tension than the upper one, and the lower part of the box girder is mainly under tension, and the upper part is mainly under compression. The maximum internal force of scissors braces is 16kNs, which exceeds the theoretical anti-slip strength of double-row fasteners. Therefore, special selection of high-quality fasteners should be adopted in the joint strength of shear-braces, and not less than three. The angle between inclined brace and formwork under flange should be less than 90 擄, and the upper and lower parts should be close, and the connection fastener should be not less than 3.
【學位授予單位】：鄭州大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：U445.57

【參考文獻】

相關期刊論文 前10條

1 馮天焱;;公路橋梁現(xiàn)澆箱梁模板與支架設計施工淺析[J];廣東科技;2009年14期

2 衣振華;李瑞平;;碗扣式腳手架支撐在橋梁施工中的應用[J];公路;2005年12期

3 劉顯鳳;;簡析橋梁掛籃懸臂施工法[J];建材世界;2010年06期

4 衣振華;王有志;;碗扣式腳手架支撐在橋梁施工中的計算模型[J];工業(yè)建筑;2006年S1期

5 佘步銀;郭正興;;高支模架結構安全策略思考及設計方法[J];工業(yè)建筑;2011年01期

6 方立新;宣云干;;扣式連接結構的節(jié)點半剛性模型探討[J];江蘇建筑;2008年01期

7 李維濱,劉桐 ,郭正興;扣件式鋼管模板支架安全性研究與施工建議[J];建筑技術;2004年08期

8 李萬舉;張旭;王喜燕;董鐵軍;;碗扣式腳手架在現(xiàn)澆橋梁施工中的計算及應用[J];建筑技術;2010年09期

9 任永安;;碗扣式滿堂腳手架立桿穩(wěn)定性計算[J];山西建筑;2010年25期

10 胡昊;;碗扣式與鋼管扣件式超重平臺結構排架支撐體系的對比[J];建筑施工;2012年03期

相關博士學位論文 前1條

1 高秋利;碗扣式鋼管腳手架和支撐架受力性能試驗與分析[D];天津大學;2011年

本文編號：1684015