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1.背景材料某大桥位于长江的支流,桥垮为2×30m+5×45m。两岸桥台采用重力式桥台,基础为扩大基础;墩为柱式墩,基础为桩基础;上部为预应力简支T梁。1)该大桥的施工组织设计有以下内容(1)编制说明;(2)编制依据;(3)工程概况;(4)主要工程项目的施工方案;(5)施工进度计划;(6)各项资源需求计划;(7)施工总平面图设计;(8)季节性施工技术措施。2)有关分部(分项)工程的施工方案和方法描述如下(1)桥梁0号桥台和7号桥台基础施工0号桥台和7号桥台设计为浅埋扩大基础,基础置于中风化或微风化的岩层上,风化带浅基岩层覆盖层薄。由于常年有水,故采用围堰施工。施工顺序为基础开挖→围堰施工→基础排水→安装模板→绑扎钢筋→浇筑混凝土。(2)桥梁1号桥墩和6号桥墩桩基础和承台施工1号桥墩和6号桥墩桩基础设计为钻孔灌注桩基础。该段河床泥面较高,风化层较厚,施工方法为在1号桥墩和6号桥墩位置所筑的岛上用钻机全护筒钻孔和灌注混凝土。钻孔桩完成后打钢板桩围堰,抽水浇筑承台。施工顺序为筑捣→钻孔桩施工→围堰施工→水中基坑开挖→抽水→封底→安装模板→绑扎钢筋→浇筑混凝土。(3)桥梁2号桥墩至5号桥墩桩基础和承台施工2号桥墩和5号桥墩处堰面起伏较大、水深,设计的钻孔灌注桩要求嵌岩较深。考虑到由于水深筑捣做围堰较困难,决定使用钢管桩搭设施工平台,轻型冲击钻机施钻,钻孔桩完成后,利用平台吊装钢套箱就位,然后进行承台施工。具体施工方法如下①沉入钢管桩作为施工平台的支撑,用贝雷梁片组成平台骨架,上铺方木形成平台。②在平台上先打入8mm厚的钢板制成的内径比桩径大25cm的护筒,作为钻孔桩的护筒。使用定位架保证定位准确。③安装钻孔设备后,进行钻孔。对于河床的淤泥覆盖层用冲抓钻的抓斗清除,而岩层则用轻型冲击钻机成孔。④终孔检查合格后,应迅速清孔,采用清水换浆法。清孔时必须保持孔内的水头,提管时避免碰孔壁。⑤清孔完成经成孔检查合格后即可进行钢筋笼的吊装工作。钢筋笼接长时每根钢筋应在同一横截面按规范要求的搭接长度进行焊接。钢筋笼安放应牢固,以防止在混凝土浇筑过程中钢筋笼浮起,可在钢筋笼周边安放圆形混凝土保护层垫块。⑥钢筋笼安放完成后,进行混凝土灌注。水下混凝土采用导管法进行灌注,导管使用前应进行闭水试验(水密、承压、接头抗拉)。施工中导管内应始终充满混凝土。随着混凝土的不断浇入,应及时测量并提拔拆除导管,使导管埋入混凝士中的深度保持在2m以内。⑦钻孔桩完成后,利用平台沉放钢套箱进行承台的施工。将钢套箱内的泥面整平后紧接进行相关的工序。(4)桥梁下部墩身施工承台混凝土达到规定强度要求后,即进行墩身混凝土施工。墩身分为上下两节施工,上节高6m,下节随墩高变化而定。施工顺序下节模板安装一下节钢筋绑扎一下节混凝土浇筑一上节模板安装一上节钢筋绑扎一上节混凝土浇筑。(5)桥梁上部后张法预应力T梁预制要点①T梁预制台座的建造根据地形选择0号桥台这侧河岸的一块高地整平压实后作为T梁的预制场。台座用表面压光的梁(板)筑成,台座应坚固不沉陷,以保证底模不沉降。台座上铺钢板底模并考虑与侧模的连接,钢板底模和台座应保持水平。②钢筋骨架制作、预应力孔管道的固定和压浆孔的设置在绑扎工作台上将钢筋绑扎焊接成钢筋骨架,把预应力孔管道按坐标位置固定,并用龙门吊机将钢筋骨架吊装入模。在孔道两端设置压浆孔,在最低处设置排气孔。③混凝土浇筑、预应力张拉和压浆混凝土浇筑达到强度后,按规范要求进行预应力张拉。张拉控制应力达到设计要求后立即进行预应力钢筋锚固。在孔道冲洗干净吹干后,用压浆泵从梁两端压浆孔各压浆一次,直到水泥浆充满整个孔道为止。(6)桥梁上部预应力T梁吊装T梁吊装采用双导梁架桥机架设法。2.问题(1)补充完善一般施工组织设计应包含的内容。(2)请对桥梁施工方案和施工方法的描述作出评价①桥台基础施工中的施工顺序正确与否?说明理由。②1号墩和6号墩的桩基础与承台的施工顺序是否正确?说明理由。③2号墩~5号墩的桩基础的施工方法逐点评价是否正确?说明理由。④写出2号墩~5号墩的承台施工相关工序的顺序。⑤桥梁下部墩身施工顺序正确与否?说明理由。⑥对后张法预应力T梁预制要点逐点评价其正确与否?说明理由。⑦评价T梁吊装采用双导梁架桥机架设法的正确与否?说明理由。

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From childhood to old age, we all use language as a means of broadening our knowledge of ourselves and the world about us. When humans first 1 , they were like newborn children, unable to use this 2 tool. Yet once language developed, the possibilities for human kind’s future 3 and cultural growth increased. Many linguists believe that evolution is 4 for our ability to produce and use language. They 5 that our highly evolved brain provides us 6 an innate language ability not found in lower 7 . Proponents of this innateness theory say that our 8 for language is inborn, but that language itself develops gradually, 9 a function of the growth of the brain during childhood. Therefore there are critical 10 times for language development. Current 11 of innateness theory are mixed, however, evidence supporting the existence of some innate abilities is undeniable. 12 , more and more schools are discovering that foreign languages are best taught in 13 grades. Young children often can learn several languages by being 14 to them, while adults have a much harder time learning another language once the 15 of their first language have become firmly fixed. 16 some aspects of language are undeniably innate, language does not develop automatically in a vacuum. Children who have been 17 from other human beings do not possess language. This demonstrates that 18 with other human beings is necessary for proper language development. Some linguists believe that this is even more basic to human language 19 than any innate capacities. These theorists view language as imitative, learned behavior. 20 , children learn language from their parents by imitating them. Parents gradually shape their child's language skills by positively reinforcing precise imitations and negatively reinforcing imprecise ones. 请在6处填上()

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