土木工程材料答案.doc

表观密度：表观密度是指单位表观体积材料的干质量毛体积密度：指单位毛体积的干质量 润湿边角确定材料是亲水还是憎水材料与水有关的性质：耐水性：材料在水的作用下不被破坏，或不严重降低强度的性质称为耐水性。用软化系数kp表示。 抗渗性：材料抵抗压力水渗透的性质称为抗渗性。由渗透系数ks表示。 材料的抗渗性与材料内部的孔隙率，特别是开口孔隙率有关，开口孔隙率越大，大孔含量越多，则抗渗性越差，还与材料的憎水性，亲水性有关，材料的抗渗性与材料的耐久性有这密切的关系！ 抗冻性：材料在水饱和状态下，能经受多次抗冻融循环作用而不被破坏，也不严重降低强度的性质，称为材料的抗冻性。材料的抗冻性取决于其孔隙率，空隙特征，及充水程度。简答：试分析材料的孔隙率与空隙特征对材料的强度、吸水性、抗渗性、抗冻性、导热性的影响。强度：不同种类的材料抵抗外力的能力不同，同类材料当其内部的构造不同时，其强度也不一样，致密度越高的材料，强度越高！吸水性：孔隙率越大，同时开孔越多，连通孔越多，吸水性就好。抗冻性：与吸水性相反，吸水性越好，抗冻性越差。抗渗性：越吸水性一致，同时，孔的连通性对于其有着特别的影响，是其主要影响方面。导热性：孔隙率一定，连通孔越少，导热性越差，开孔与否无关紧要，如果孔隙特征不变的的话，一般情况下孔隙率越大，导热性越差。低碳钢：碳的质量分数小与0.25%的钢 （牌号划分依据）按质量等级划分：普通钢，优质钢，高级优质钢，特级优质钢无机胶凝材料石灰（原料）石灰石、白云石、贝壳、白垩（碳酸钙）产生裂纹的原因：其一，石灰在硬化过程中，要蒸发大量的水分，引起体积显著收缩，易出现干缩裂纹。（在其中参入砂，纸筋，以现在其收缩，并能节约石灰。）其二，过火石灰表面常被黏土杂质融化形成的玻璃釉状物包裹，熟化较慢，当石灰已经硬化后，其中的过火颗粒才开始熟化，体积膨胀，引起隆起和开裂。（为消除过火石灰的危害，石灰膏应在储灰坑存放俩个星期以上，这个过程被称为石灰的陈伏）建筑石膏的特点：1，凝结硬化快。建筑石膏加水拌合后的浆体初凝时间不小于3min，终凝时间不早于30min，7d左右完全硬化。2，硬化初期有微膨胀性。其他胶凝材料在硬化过程中往往产生收缩，而石膏略有膨胀，而且不开裂。3，孔隙率高，石膏制品容重小，隔热保温性能好，吸音性强。4，防火性能好，遇火时，结晶水蒸发，降低表面温度，脱水后又是良好的绝热体，起到防火的作用。硅酸盐水泥的主要熟料矿物的名称 硅酸三钙 3CaO.SiO2 硅酸二钙 2CaO.SiO2（最慢，最少） 铝酸三钙 3CaO.Al2O3（凝结硬化速度最快，28d水化放热量最大） 铁铝酸四钙 4CaO.Al2O3.Fe2O3影响水泥凝结硬化的因素1.养护时间2温度湿度3石膏参量（1熟料中铝酸三钙含量高，石膏参入不足，水泥会发生快凝2水泥的细度越细，水化作用越快，凝结就会越快3水灰比越小，凝结时的温度越高，凝结就越快4混合材料参量大，水泥过粗，都会使水泥凝结缓慢）硅酸盐水泥的技术性质 1细度：水泥颗粒的细度对水泥的性质有很大的影响。颗粒越细，与水反应的表面积就越大，水化较快而且完全，早期强度也比较高。2凝结时间：分为初凝和终凝。初凝：为水泥加水拌合起至标准稠度净浆开始失去可塑性所需的时间；终凝：为水泥加水拌和起至标准稠度净浆完全失去可塑性并开始产生强度所需的时间。Whats 级配？ 沙石的级配是指沙石种不同颗粒的分布情况。良好的级配应能使沙石的空隙率和总表面积均较小，以达到节约水泥，提高混凝土密实性及其强度的目的。 沙的级配用细度模数表示：普通混凝土的基本技术性质：（和易性、强度、耐久性）和易性：是指混凝土拌合物易于施工操作，并获得质量均匀，成形密实混凝土的性能。影响因素：1水泥浆的数量和水灰比的影响。在水灰比不变的情况下，单位体积拌合物内，水泥浆越多，拌合物的流动性越大。2砂率的影响，实验证明，砂率对拌合物的和易性有很大影响。3组成材料性质的影响。（1）水泥。水泥对拌合物的影响主要是水泥品种和水泥细度的影响。（2）骨料。骨料对拌合物的影响主要包括骨料级配、颗粒形状、表面特征及颗径。（3）外加剂。外加剂对拌合物的和易性有很大影响。温度和时间的影响。混凝土拌合物的流动性随温度的升高而降低。影响强度的因素：1水泥强度等级和水灰比。水泥强度等级和水灰比是影响混凝土抗压强度的主要因素。2龄期。混凝土在正常养护条件下，其强度将随着龄期的增加而增长。3养护的温度和湿度。混凝土养护的温度和湿度是影响其强度的主要因素，温度和湿度都是影响水泥的水化过程而起作用的。什么是胶凝材料 在砂浆中起着胶结的作用的材料，它是影响砂浆流动性、黏聚性和强度等主要性质的主要组分。红砖：当以黏土为原料时，焙烧过程中，铁被氧化成红色的高价铁，所以叫红砖青砖：当温度过高，高价铁被还原成青灰色的低价铁，成青灰色，叫青砖。泛霜：泛霜是指黏土为原料中的可溶性盐类，随着砖内水分蒸发而在砖表面产生的盐析现象石灰爆裂：当黏土含有石灰石时，焙烧时，会生成过火生石灰留在砖内，这些生石灰在砖内吸收外界的水分，消化并产生体积膨胀，导致波坏，这种现象被称为石灰爆裂。什么是沥青材料：是由一些极其复杂的高分子碳氢化合物和这些碳氢化合物的非金属的衍生物所组成的混合物，是一种褐色或黑褐色的有机胶凝材料。性质（憎水性，在常温下呈固态，半固态，或黏性液体。能与砂石，砖，混凝土，等材料牢固的凝结在一起，具有良好的耐腐蚀性）石油沥青三大组分，油分、树脂、沥青质油分：赋予沥青以流动性，油分的多少直接影响沥青的柔软性、抗裂性以及施工难度。树脂：主要使沥青具有塑性和黏性。沥青质：决定着沥青的粘结力。黏度和温度稳定性。蜡对沥青的影响：它会降低石油沥青的粘结性和塑性，并对温度很敏感。是有害成分，在高温时，会使沥青变软，导致沥青路面高温稳定性降低，出现车辙。低温会使沥青变脆，抗裂性降低，出现裂缝。粘附性降低，在有水的条件下，会使路面石子产生脱落，造成路面破坏。影响行车安全。无论你是多么富有经验的演说家，无论你做了多么充分的准备你都很难在这样的嘈杂的招待会下发表演说（no matter how）No matter how experienced a speaker you are, and how well you have prepared your speech, you will have difficulty making a speech at such a noisy reception.就像吉米妹妹的朋友们关系吉米一样，吉米也关心他们（just as）Just as all his sisters friends cared about him, Jimmy cared about them.老师回来时你敢告我的状的话，我就不再和你说话了（tell on）. If you dare tell on me when the teacher gets back I wont say a word to you any more.有些老年人愿意独自过日子，但多大多数老人选择和儿女一起生活（on ones own）Some elderly people prefer to live on their own while the great majority choose to live with their children.When someone does something for you ,no matter how small and no matter whether he is superior or inferior ,it is proper to say “ thank you”每当有人帮了你，无论事情大小，无论他地位高低，你都应该对他说声“谢谢”。The invention of the steam engine changed ships just as it had changed land transport 蒸汽机的发明使船舶发生了变化，正如其已经改变了陆地运输一样。Though the manager did his best to help ,he was still unable to track down the source of the problem 尽管经理努力帮忙，他还是不能找到问题的根源所在。The girl ,whose life revolved around her brother ,had no difficulty working out what she should do to please him 这个女孩的生活天天围着哥哥转，完全明白该做什么来使哥哥高兴。Jimmy had his sister to help him get through the painful days alone without his father 吉米有他妹妹帮助他度过那些没有父亲的艰难日子。被告是为年仅32岁的女子，她坚持自己无罪（use an appositive）The defendant, a woman of only 30, kept insisting on her own innocence.正餐时不供应饮料，饮料会影响消化（interfere with）No beverages are served with meals because they interfere with digestion.考虑到那个地区受欢迎程度，提前订旅馆是明智的（advisable）Taking the popularity of the region into consideration, it is advisable to book hotels in advance服药后若感到呕吐感，请立即停止服用并尽快咨询医生（throw up）. If you have a feeling of wanting to throw up after taking this drug, stop taking it immediately and consult your doctors as soon as possible.总结这次讨论会，他说双方都要好好考虑怎样以最有效的方法来解决这一问题（sum up）Summing up the discussion, he said both parties should consider the most effective way to solve the problem.Endurance athletes , particularly females ,who frequently have iron deficiency, may bounce back if they consume additional meat or take iron supplements耐力运动员，尤其是女性，经常会缺铁，如果增食肉类食物或服用铁质补剂，能够恢复到健康状态According to the medicine expert ,it is advisable for those who suffer from fatigue and poor performance to eat red meat ,which contains the most easily absorbed form iron这位运动医学专家认为，感到劳累、工作效率差的人，最好食用牛肉、羊肉，它们含有最易被吸收的铁质People with low iron reserves should consult a physician to see if the deficiency should be corrected by modifying their diet or by taking supplements铁质储量低的人应该去咨询医生，看看是否应通过调整饮食或服用铁质补剂来校正不足。In general ， if you ignore the amount of the iron you take in and do not pay attention to warning signs before iron reserves are gone ,you will be in trouble 一般说来，如果你忽视自己摄入的铁质含量，不在铁质储备失去之前注意警告信号，你会有危险在思维方面，与他的行为一样，他是非常传统的In his thinking, as in his behavior, he is very traditional从长远看，大学毕业后继续深造而不是直接参加工作是值得的（in the long run,worthwhile）In the long run, it is worthwhile to pursue ones study after graduating from university instead of going to work directly.据说，原定于这个月召开的会议将推迟到下个月召开（be scheduled to, put off）It is said that the meeting, which is scheduled to be held this month, will be put off till next month.As in France , during the 1906s in the United States there was a cultural revolution.跟在法国一样，美国在20世纪60年代也发生过文化革命。The school stresses the ideal that it is worthwhile for parents to participate in school activities together with their children 学校强调的观点是：家长和孩子一起参加学校的活动是值得的。At the end of the class ,the teacher asks her students to spend the last five minutes in an energetic exchange evaluating their class performance for the day on 1-10 scale快下课时，老师让学生用最后的五分钟来展开激烈的讨论，依照110的评分标准相互评价他们当天的课堂表现。Not all parents believe in Hyde Schools principle that if you teach students the merit of such values as turth , courage , integrity, leadership ,curiosity and concern ,then academic achievement naturally follows并非所有的家长都相信海德中学的办学原则，即如果你向学生传授诸如求真、勇敢、正直领导能力、好奇心和关心他人等美德的话，学生的学习成绩就自然会提高。从各个方面考虑，这座城市都是世界上最令人激动的城市. Everything considered, this city is the worlds most exciting city.尽管没有得到父母的同意，她还是计划他的计划出国学习Though with no approval from his parents, he went ahead with his plan to study abroad.这座桥是以一个英雄的名字命名的，这位英雄为人民的事业献出了自己的生命（name after）The bridge was named after the hero who gave his life for the cause of people.据说，画家是以他母亲为模特的。他母亲的面容沧桑却不失坚定（it is said）It is said that the painter used his mother as the model in the painting whose face represented suffering yet strength.这位作家于1905年因出版一本小说而一举成名，小说的灵感来自于他和一位姑娘在农场的经历（rise to fame）The writer instantly rose to fame in 1950 with the publication of a novel inspired by his experience with a girl on a farm.The painting shows a serious-looking man and a women standing alongside him front in of a farm house, their models being respectively the painters dentist and sister这副画上一个神色严肃的男子，身旁站着一位女子，身后是所农舍。他们的原型分别是画家的牙医和姐姐。Applications made by corporations, whether on their own behalf or on behalf of other persons, muse be signed by an official 公司的申请书，不管是代表自己还是代表他人，都应该有官员的签名After starting out in talk show , John rose to fame with his wife in radio and television programs that enlightened the general public, not just informed them做了脱口秀之后，约翰和妻子在广播和电视节目上出了名，这些节目给普通民众以启迪，而不只是向他们提供信息Although some people did not approve of it, the city leaders decided to go ahead with the plan to build two five-star hotels by the lake to attract more visitors尽管有些人不赞同，可市领导还是决定实施这个计划，在湖边建造两个五星级宾馆，以吸引更多的游客。The famous painter died, and his wife, who used to be a model posing for his drawings, immediately came in as a general of his decoration company 那位著名画家去世了，曾经给他当模特的妻子立即担任了他装潢公司的总经理职务。At the party, all of them were richly dressed, but it was their way of talking that captured my attention so much that I feel inclined to talk with them宴会上，他们的衣着都很华丽，但吸引我注意力的却是他们的交谈方式，使得我很想和他们交谈。直到看见弥留之际躺在床上的母亲，他才意识到自己是多么地爱她Not until he saw his mother lying in bed, dying, did he realize how much he loved her.考虑到他最近的身体状况，我认为他这次考试成绩还不错Taking into account of his recent physical condition, I think he has done quite well in the exam.克拉克夫人躺在场上一动不动，一时间我都纳闷他是否还活着（wonder if）Mrs. Clark lies in bed motionless, and I wondered briefly if she is still alive.整栋楼一片黑暗，只有三楼的某个窗户透出一丝光（expect for）The building was darkened except for a single light burning in a third-storey window.这些士兵接受了严格的训练，并且对完成这项任务有充分的准备（be equipped）These soldiers have received very strict training and are well equipped to fulfill the new task.她伸手拿起电话，拨通宾馆的号码（reach for）He reached for the phone, picked it up, and dialed the hotels number.Not until the early sixties did it seem it to be generally acknowledged that Britain was no longer a great power as previously understood直到60年代早期，人们似乎才普遍认同英国不再是以前心目中那样的大国了。Having decided to rent a flat, we set about contacting all the accommodation agencies in the city 在决定了租房之后，我们便着手与市内所有的房屋代理商联系。I clean her body carefully, trying to avoid hurting her, as she is only skin and bones 我小心翼翼地替她擦身子，尽量避免弄疼她，因为她瘦的只剩皮包骨了。There is a swell of emotion within me for this old man who is dying, his dark yellow skin hanging loosely around exaggerated bones, his sunken chest rising and falling with the uneven breaths 我心间对这位老人涌起了一股感情。他那暗黄的皮肤松弛地裹在显得异常大的骨头上，深陷的胸部随着不均匀的呼吸一起一伏。Did you read about the famous painter in the newspaper? He actually worked himself to death for his ambition of becoming a master of visual art 你在报上读到那位著名画家的消息了吗？他实际上是为了要成为视觉艺术大师的抱负而累死的。There had been hints that the old lady wanted to die alone, sparing her family am episode that perhaps they were not equipped to handle 有迹象表明，这位老太太想孤独地离开人世，不让她的家人看到他们或许无力面对的人生插曲。我们应该尽最大的努力预测地震，这样地震造成的财产破坏才会被尽可能避免（so that）一个农民注意到很多鱼在水面上游动，他说这很可能预示着有地震发生（which）要将英汉词典放在手边，当你不能准确地理解单词时，你就能随时查阅（keep sth. handy）如有必要，生活在将要发生地震地区的人可以睡在帐篷里（if necessary）对一个想找工作的学生来说，有没有硕士学位的确有很大影响（make a difference）这本书除了告诉我们地震方面的知识外，还告诉我们如何做好预防工作（in addition to ）As most of the people who died in earthquakes are killed by falling buildings ,building structures must be improved so that they can withstand the power of earthquakes People should have supplies of water and food at home and at work, which is especially necessary in possible occurrence of an earthquakeIn both Japan and China, people have long believed that earthquake can be forecast by watching the behavior of animals Besides working to improve building structures, people in areas where earthquakes are common should prepare for the possibility of a great earthquake in several other aspectsIt is sensible for every family to make earthquake emergency plans and all the family members should know how to leave the area during the chaos following earthquakeAs the few remaining working telephone lines will be very busy ,all of the family members should call to check in with a friend or relative who leave far away from the earthquake stricken area因此，以盖茨为首席执行官的微软还能走多远依然是个有趣的问题（as to） An interesting question therefore remains as to how far Microsoft can go with Gates as its CEO.抱怨是没有用的，因为抱怨并改变不了什么，重要的是的采取措施预防类似事件的发生Theres/Its no use complaining since nothing ever changes as the result of a complaint. Whats important is to take measures to prevent similar events from happiness.要学会接受这样一个事实：有些你认为是朋友的人结果是敌人（turn out）Learn to accept the fact that some people you thought were friends turn out to be enemies.正如你能从书名期待的那样，书里多处提到盖茨是怎样的人（expect to）As you would expect from the books title, there are many references to what kind of man Gates is.该公司的兴隆源于公司上下人人克勤克俭（steam from）The prosperity of the company stems from hardworking and thrifty of the entire staff.就星期六晚上上演的那出戏，他什么也没说（on the subject of）He said nothing at all on the subject of the play which was put on for the first time Saturday night.I have in fact no explanation to offer as to how he died that evening ,and it may be that no possible explanation will ever be given . 至于那天晚上他是怎么死的，事实上我无法解释，而且也许不会有任何可能的解释了There is no use doing something and then saying you did not mean to do it, had you mean to do it, you would not have done it 做了一件事然后说自己本来不想那样做是没有用的；如果你不想做，你就不会做了。Microsoft is working on ways to reduce the cost of its products so that people in developing countries can afford them 微软公司正在研究降低其产品成本的方法，以便发展中国家的人也能买得起。Apple also will bundle some of its software with Microsoft products to help boost its sales 苹果公司也愿意将其部分软件与微软公司的产品捆绑在一起，以促进其销售。Unlike fathers, mothers are judged by their parenting successes or failures, for mothers, every thing depend on how their kids turn out与评价父亲不同，人们评价母亲依据的是其为母之道的成功或失败。对于母亲来说，一切都取决于孩子最终成为什么样的人。People will find the website invaluable as we have put in a lot of time to prepare the information 人们会发现这个网站很有价值，因为我们投入了大量时间准备网站保证杆件正常工作的基本要求：具有足够的强度、刚度、稳定性材料力学研究对象的基本假设：连续性假设，均匀性假设、各向同性假设内力：杆件内部之间的相互作用力比例常数E为弹性模量（材料的固有性质）拉伸的四个阶段：弹性阶段、屈服阶段、强化阶段、局部变形阶段力偶矩推导等直圆杆扭转时横街面上切应力的计算公式所需要考虑的综合条件：先从几何方面和物理方面求得切应力在横截面上的变化规律，然后再从静力学方面来求解。单位长度扭转角：刚度通常用相对扭转角沿杆长度的变化率，即单位长度扭转角荷载的微分关系及其物理意义： 对弯矩函数求导，得剪力函数，对剪力函数求导，得均布荷载q塑性材料和脆性材料 许应拉应力与中兴轴的微分关系？梁变形后俩个基本物理量 挠度、转角边界条件：挠度和转角都为0 的点提高梁的刚度条件：增大梁的弯曲刚度EI、调整跨长和改变结构拉压超静力问题的综合求解条件：运用变形的几何相容条件力-变形间的物理关系和静力学的平衡条件三方面来求解应力状态：受力杆件内一点处不同方位截面上应力的集合，称为一点处的应力状态一点处切应力等于0的截面称为主平面，主平面上的正应力称为主应力材料破坏的基本类型：脆性断裂、塑性屈服组合变形：若几种变形所对应的应力属于同一数量级，则构件的变形称为组合变形按叠加原理计算组合变形横截面上的正应力时，忽略了那些？截面核心：当外力作用点位于截面型心附近的一个区域内时，就可以保证中性轴不与横截面相交，这个区域称为界面核心临界压力：中心受压直杆在直线形态下的平衡，由稳定平衡转化为不稳定平衡时所收轴向压力的界限值，称为临界压力欧拉公式适用范围：