Three Men in Boat Essay Example for Free

Three Men in Boat Essay The book is narrated in the first person by the author, who is referred to as J by his friends. It begins with J, and his friends harris and George, deciding to take a boat trip up the Thames from Kingston to oxford, and then back again (the book was written in 1888, when boating on the Thames was enormously popular). They are unanimous in agreeing that this is a good idea (except for Js dog, Montmorency, who doesnt care for boating). They have trouble getting packed, and in the morning Harris and J take a train to Kingston, where the boat is waiting for them. George is joining them later when he has finished his work at the bank. They row up past Hampton Court, where Harris describes an incident when he got lost in Hampton Court maze with some friends (this is one of the funniest parts of the book). George joins the party, and they have trouble towing the boat, and later they have even more trouble trying to put the cover over the boat for the night. They all get fed up with each other, but cheer up when they have a good Tea. There is a long passage about the signing of Magna Carta (there are several passages like this in the book, where the author gets serious for a bit). They have various other mishaps as they travel up the river, like the time when they are having tinned pineapple for tea, and cant find the tin-opener. They spend a lot of time trying to open it with no success. And there are stories of other trips they made up the river, like the time J was ou tin a boat with his cousin, and they thought they were going crazy because they couldnt find Wallingford Lock (it turns out the lock had been demolished some years earlier). And there ere is the time when they are in an inn which has a stuffed trout in a case on the wall, and several different people come in and claim to have been the one who caught it, but when George stands on a chair to look at it, he knocks it down and it breaks it turns out to be plaster of Paris! When they reach Oxford, and start to travel back, it starts to rain, and they arent enjoying themselves so much. So they abandon the boat and take the train back to London, where they go to a show and then have a good dinner in a restaurant. They make a toast Heres to three men well out of a boat!

Simon as Silent Prophet of Lord Of The Flies Essay -- Lord Flies Essay

Simon as Silent Prophet of Lord Of The Flies  Ã‚        Ã‚  Ã‚  Ã‚  Ã‚   The role of the prophet changes with the society in which he lives. In Modern America, a prophet is a visionary, telling his people what they can become; in Biblical times, a prophet was the voice of God, telling his people what they had to become to fulfill their covenant with God. In William Golding's Lord of the Flies, though, the prophet told his people nothing; he realized what they had already become, and he dared not tell them because he knew they would turn against him. Simon lived in knowledge and fear because his society denied the role of the prophet, and he did not fight it because he wanted so much to be part of that society.    The basic premise of Lord of the Flies is that humans naturally live in savagery and ignorance, without any idea of how to live together. It is the story of boys stranded on an island who must develop a government to survive. Every detail of the story holds symbolism. For example, each character represents an aspect of society : those who represent human nature survive, and those who are self-actualized--the scientists, the religious, the leaders--all die. The most terrifying death is that of Simon, who symbolizes the eyes of a blindfolded and stumbling people. He alone saw that the jungle, which represented freedom and the lack of civilization, was not to be feared but to be understood; he alone knew that the mythical Beast of the island, feared by all the boys, was in fact their own inherent savagery. (The title, Lord of the Flies, is in fact a translation of "Beelzebub," a name of the devil in the Judeo-Christian tradition).    In a vision, the Beast told Simon: "Fancy thinking the Beast was something you could hu... ... his fear, his compatriots' savagery justifies that weakness. If his flaw was his desire to be accepted, then he was no different from any of the other boys. Simon was just as human as all the children on the island, abandoned to "the end of innocence, the darkness of man's heart" (202). If the truth died with Simon, it died because human nature hates prophets, because humans naturally live in savagery and ignorance.    Works Cited Epstein, E.L. "Note on Lord of the Flies." Lord of the Flies. U.S.A.: Puntnum Publishing Group, 1954. Golding, William. Lord of the Flies. U.S.A.: Puntnum Publishing Group, 1954. Golding, William. "Lord of the Flies as Fable." Readings on Lord of the Flies. Ed. Bruno Leone. Sand Diego: Green Haven Press, 1997. Riley, Carolyn, ed.   Vol. 1 of Contemporary Literary Criticism. Detroit: Gale Research Company, 1973.   

Sociological Theories

This theory has caught the attention of the nation, and the federal government has taken steps to roved assistance in lower income and poverty stricken areas. One of the main programs that have been implemented into these lower income areas are Yam's. The goal behind the YMCA is to bring sports, and other activities into the lower income areas and keep juveniles busy within the YMCA and keeping these kids off the streets and out of trouble. The second theory is the Social Process Theory.The Social Process Theory is based upon the belief that colonization is key in determining ones behavior. If colonization is absent or portrayed in a negative manner, it can cause venires to act out in feel alienated from normal social behaviors. Children who feel isolated from their peers and do not have a loving environment at home are more likely to be involved in delinquent behavior. These children often turn to drugs or alcohol as an answer. An example of both state and federal funded program tha t assists with the Social Process Theory is the D. A. R. E Program.The D. A. R. E program is designed to prevent kids from using drugs, engaging in violent and criminal acts and encourages them to engage n normal social behaviors with other kids their age. The third theory is the Social Conflict Theory. The Social Conflict Theory is a belief that our entire society is in a constant state of internal conflict, with various groups trying to impose their belief on others. The Social Conflict Theory suggests that those of wealth and power help define laws to meet their specific needs while ignoring the needs of the rest of society.It is believed that adolescents that do not fit into the needs of the powerful members of society are labeled criminal delinquents. Those that suffer the most from social conflict are people of color or those living in poverty stricken areas. An example of a program that targets the youth suffering from the social conflict program is Promising Practices Networ k. The Promising Practices Network is a school based violence prevention program that serves over 400 public schools in poverty stricken areas. This program is designed to fight prejudice, stereotypes and other types of violence.As shown here these three sociological theories are vital ways to view the issues related to juvenile delinquency. The programs related to each of these theories are extremely beneficial to lowering crime rates among juveniles. I truly hope that we continue to fund these wonderful programs, as it benefits the future of America. Sociological Theories Chapter one there are three different types of sociological theories. The three types are functionalist theory, conflict theory, and symbolic theory. We will cover and talk about the differences. First is the functionalist theory. The functionalist theory is when the people who live in the area are all part of a bigger plan. Everyone there is an equal no one has more than anyone else. When I think about functionalist I think of farm. As in like the whole community works on the farm like someone feed and mike cows and someone male food the cows eat so and and so forth. August Comte and Herbert Spencer viewed society as a kind of living organism. When all the people are working together is called normal and when there not it’s abnormal The conflict theory provides a third perspective on social life. Unlike the functionalists, who view society as harmonious whole, with its parts working together, conflict theorists talk about society being composed of groups that are competing with one another for scarce resources. Karl Marx is the founder of this theory. This is like slavery to me because slaves worked for a higher power for very little are no pay at all. Soon people get mad and rise up to the greater power and demand a change. The last one is symbolic theory witch is when people develop and share their views of the world, and focus on micro level. This is like used when people back in the day didn’t read and right. The easy way to talk to people is with pictures. They are easy to understand than writing. There are many differences between these things. For one they were all made up in different area of times, and locations in the world. All the theories are made but by different people, and they had their way of thinking of it. They all apply for different part of life, but very close. One thing they do haven common is that they all related to groups of people. Is takes a group of people to make it work. All these theories have happened in some part of the world. Not only have they happen they still happen in today society. Finally in collection there is nothing new under the sun, and the same things they are talking about there are happing now. And all these theories can be facts. Sociological Theories This theory has caught the attention of the nation, and the federal government has taken steps to roved assistance in lower income and poverty stricken areas. One of the main programs that have been implemented into these lower income areas are Yam's. The goal behind the YMCA is to bring sports, and other activities into the lower income areas and keep juveniles busy within the YMCA and keeping these kids off the streets and out of trouble. The second theory is the Social Process Theory.The Social Process Theory is based upon the belief that colonization is key in determining ones behavior. If colonization is absent or portrayed in a negative manner, it can cause venires to act out in feel alienated from normal social behaviors. Children who feel isolated from their peers and do not have a loving environment at home are more likely to be involved in delinquent behavior. These children often turn to drugs or alcohol as an answer. An example of both state and federal funded program tha t assists with the Social Process Theory is the D. A. R. E Program.The D. A. R. E program is designed to prevent kids from using drugs, engaging in violent and criminal acts and encourages them to engage n normal social behaviors with other kids their age. The third theory is the Social Conflict Theory. The Social Conflict Theory is a belief that our entire society is in a constant state of internal conflict, with various groups trying to impose their belief on others. The Social Conflict Theory suggests that those of wealth and power help define laws to meet their specific needs while ignoring the needs of the rest of society.It is believed that adolescents that do not fit into the needs of the powerful members of society are labeled criminal delinquents. Those that suffer the most from social conflict are people of color or those living in poverty stricken areas. An example of a program that targets the youth suffering from the social conflict program is Promising Practices Networ k. The Promising Practices Network is a school based violence prevention program that serves over 400 public schools in poverty stricken areas. This program is designed to fight prejudice, stereotypes and other types of violence.As shown here these three sociological theories are vital ways to view the issues related to juvenile delinquency. The programs related to each of these theories are extremely beneficial to lowering crime rates among juveniles. I truly hope that we continue to fund these wonderful programs, as it benefits the future of America.

Workplace Observation Essay - 1143 Words

My paper will talk about the communication in our department and company wide. The next topic my paper will talk about is culture that exists in our organization for safety in the workplace and home. Then we will move into a process that our company have which address conflict in the workplace. Finally, the technology enhancements that we have changed to improve our process, address customers concerns, and automation of some of our service we offer to our customers, which include our meter reading department. Communication PECO Energy offers various types of communication in our organization. The types of communication can range from emails to voice mails depending on the type of information communicated to the timeliness†¦show more content†¦Our organization focus on and reinforce the behaviors needed to have a safe environment. We have frequent fire drills, every meeting has a safety feature and communication on safety is done weekly at our tailgate meetings. We also offer defensive training, screener safety during storms, equipment readiness, and now we moved to home safety, which gives reminders during season changes. We utilize the STAR principle, which means Stop, Think, Act and Review. This helps inside the workplace to keep all employees alert to report any unsafe conditions. This is also incorporate in our overall mission statement and in each employees Performance Reviews. We also have in place two types of analysis which will be conducted when an unsafe condition exist . The first report is called an ACE, which means an Apparent Cause Evaluation, and the second report is called a RCA, which means a Root Cause Analysis. These process can be used to analyze the root cause of an even and recommend the necessary corrective actions that need to be taken then this information is shared within the organization to prevent future events from occurring. Conflict One way we handle conflict is through a process we call PECO SOLVE. This process is designed to offer flexible internal dispute resolution process that would encourage early resolution of employment disputes without fear of retaliation, to promoteShow MoreRelatedEssay on Workplace Observation810 Words   |  4 PagesWorkplace Observation Corporations are the building blocks for communities, counties and cities. They have their own agendas and can impact these areas in minute and monumental ways. The major factor which predicates this impact is their organizational culture. Organizational culture has been defined as, â€Å"the system of shared actions, values, and beliefs that develops within an organization and guides the behavior of its members† (Schermerhorn, Hunt Osborn, 2005). Employees are key factors whichRead More Workplace Observation Essay425 Words   |  2 PagesWorkplace Observation I am currently employed at BL pharmaceuticals, one of the largest manufactures of generic medications in the world. In this paper I will discuss how communication flows in my workplace, organizational diversity, and conflict management. With my current position as a Group Leader the flow of communication is very important. Communication Communication at BL consists of emails, work procedures and policies, telephones, and bulletin board postings throughout the facilityRead More Workplace Observation Essay746 Words   |  3 PagesIn the workplace there are many different aspects of the organization. Some of the aspects or culture of an organization are organizational diversity, dress and language, how communication flows, and organizational policies. Below I will discuss several aspects of the company I work for and define what the different cultures are. How Communication Flows As we know today there are many ways how to communicate. There is email, verbal, Internet, intranet, etc? However, there is only two waysRead More Workplace Observation Essay834 Words   |  4 Pages The organization I work for is DBS, it is a world leader in the development and manufacture of compact, professional infra-red electronic testing tools. The company was founded in 1940, it has more than 2,000 employees around the world. DBS products are used by technicians and engineers in service, installation, maintenance, manufacturing test and quality functions in a variety of industries throughout the world. I have only worked for DBS for 4 months and I am proud to be part of the organizationRead MoreWorkplace Observation Paper1144 Words   |  5 PagesAs an employee of one of the largest private universities in the world, it’s extremely important for us to be professional at all times. The University of Phoenix (UOPX) is one of the largest private universities in the worl d with over 400,000 students currently attending. UOPX strives for excellences in maintaining our commitment to educating our community. UOPX is a unique organization because; we provide opportunities to individuals that are experts in organizational policies, conflict managementRead MoreAnalysis Of The Narrative And Observation Of Auditing Alchemys Workplace1749 Words   |  7 PagesSystem Strengths Based on the information provided in the narrative and observation of Auditing Alchemy’s workplace, it appears that the organization has implemented internal control practices, policies, and procedures in an attempt to minimize organizational risk. The strengths of Auditing Alchemy’s internal control system include effective warehouse management, a perpetual inventory system, various checks and balances, and a full time security staff. The existence of these internal controls allowRead MoreThe Impact Of Diversity Training On A Group Dynamics Experiment1018 Words   |  5 Pagesanalysis and frame of reference. With the researcher as a key instrument, the researcher will collect data primarily through observation and the proceedings of the experiment will be recorded for later viewing, in order to broaden perspective and increase objectivity. (Creswell, 2014) The primary data collection approach that used for this particular research study is observations. The role of complete participant is one of the best ways to get a â€Å"true† feeling for a working diverse group. The researcherRead MoreEssay on A1 Professional Discussion1152 Words   |  5 PagesProfessional Discussion 1 A 2.2 assess candidates performance against the agreed standards Q. How do you use observation of performance to demonstrate achievement of particular standards? * Observation is used to assess the competency of a candidate in performing physical tasks in a realistic working environment, usually the workplace. * To be competent, the candidate must show that he/she has the ability to carry out a task safely against the occupational standards of the relevantRead MoreToyota1491 Words   |  6 Pagesthat they are not just doing random trial and error tests while trying to be innovative. All members of the team are encouraged to participate in the production process and it is actually said to stimulate workers and managers to engage in their workplace learning more. This scientific system grew naturally to what it is today over five decades of manufacturing. It has never been written down, it just happened. The following steps explain the Toyota structure. Rule 1: How People Work ToyotasRead MoreThe Four Levels Of Training Evaluation Is Defined As A Technique For Evaluating Training Programs1612 Words   |  7 Pagesthe worldwide standard for evaluating the effectiveness of training. The four levels of this technique incorporate assurance of how learners respond to the learning procedure, the achievement of skill acquisition by learners, the degree to which workplace behavior after the training demonstrates skill acquisition, and quantifiable outcomes, including expanded profits or decreasing any defects observed. Donald Kirkpatrick, Professor Emeritus at the University of Wisconsin and past president of the

Conflicts in an American Family in play A Raisin in the...

Conflicts in an American Family in play A Raisin in the Sun by Lorraine Hansberry The play â€Å"A Raisin in the Sun† illustrates three main conflicts in the younger family life; they are internal, social, and interpersonal. The conflicts in the story give insight as to who the characters are and what they really want out of life. Conflict is one of the underlying themes in the play, which was written by Lorraine Hansberry, it helps to tell the story and explain the situation that the Younger family is in. The characters in this story were African American, but they could have been from any ethnic group because the problems that they have to face apply to us all. Ossie Davis said it best when he said the â€Å" it didn’t really have to be about†¦show more content†¦Beneatha feels that by becoming a doctor she will have a new life (Cheney, 58). However like everything else in this play there are obstacles to overcome. The biggest obstacle is the fact that she is a black woman. In the sixties woman in general were treated unequally much less a black woman. The second obstacle is her brothers Walter â€Å"†¦ go be a nurse like other woman† (Hansberry 1.1 1019). Walter is very much opposed to his sister’s education because of the fact that he wants to use the money to fund his dream. Characters in the play, aside from fighting with each other also have to deal with their own internal struggles. The best example of this sort of internal conflict is Ruth. Ruth is pregnant and does not know what to do. She wants to get an abortion to prevent putting any more strain on the family (Cheney, 61). She also feels that by having a baby it could put more pressure on Walter and instead of him wanting to sell liquor he will start to consume it and destroy his life. Lena is another one of the characters that faces an internal conflict. Her conflict is with the money. She has full control of the check and has already used part of it for a down payment on the house she bought. The other part of the check is where her d ilemma lies. She wants to see Beneatha go to medical school, but at the same time she sees how desperate Walter is. Reluctantly she hands over control of the money to her son. SheShow MoreRelatedEssay on Compare Contrast a Raisin in the Sun1026 Words   |  5 PagesCompare and Contrast A Raisin In The Sun Essay In the play, A Raisin in the Sun, by Lorraine Hansberry, and 1961 movie written by Lorraine Hansberry and presented by Columbia pictures, one of the most important themes is the American Dream. Many of the characters have hopes and dreams. They all strive towards their goals throughout. However, many of the characters have different dreams that clash with each other. Problems seem to arise when different people’s dreams conflict with one anotherRead MoreSummary Of Lorraine Hansberry 1486 Words   |  6 PagesLorraine Hansberry, born May 19, 1930, made a very prominent contribution to society in her short lived life. She was born to a middle class family as the youngest of four children. Her father was a successful real estate broker who also founded one of the first Negro banks in Chicago (Adams 247). Lorraine’s mother was a schoolteacher named Nannie Perry who later became a ward committeewoman. In 1938, Lorraine’s father took a stand against the real estate covenants in Chicago due to the fact thatRead MoreTimeless Themes A Raisin in the Sun by Lorraine Hansberry1306 Words   |  6 Pagesnotable plays on the topic of racial minorities and family issues, A Raisin in the Sun by Lorraine Hansberry, has continued to be popular since it was written in 1959. The play is about an African American family, consisting of five members, who live in Southside Chicago during the post-World-War-Two era. The Younger family is crowded in a tiny, worn, and shabby apartment and they are fairly poor. They never have much surplus money until Walter’s father, and Mama’s husband, died and the family receivedRead MoreThe Great Playwright s Life Story2415 Words   |  10 PagesBefore the relatively short life of Lorraine Hansberry tragically ended, the African-American playwright distinguished herself in American theatre and literature as she creatively and unknowingly chall enged the views of African-American life, among other inescapable issues of the nation and the world, on the theatrical stage. The great playwright’s life story began on May 19, 1930. Although born during a time of hardship introduced by the Great Depression, Hansberry grew up rather comfortably in a middle-classRead Moreâ€Å"A Proud-Acting Bunch†: The Issues of Suburbanization and Class Stratification in â€Å"A Raisin in the Sun† 1462 Words   |  6 Pagesmiddle-class African Americans, who sought a suburban life that both â€Å"express[ed] and reinforce[d] their newly won social position.† (Wiese 101) However, this middle-class migration from urban areas left behind working class African Americans such as the Younger family of Lorraine Hansberry’s 1959 play â€Å"A Raisin in the Sun.† While the Younger family of â€Å"A Raisin in the Sun† finally realize the suburban dream of a home with â€Å"three bedrooms†¦ and a nice b ig basement† (Hansberry 92), the decision toRead More Lorraine Hansberrys A Raisin In The Sun Essay575 Words   |  3 Pages Conflict in A Raisin in the Sun amp;#9;In the play A Raisin in the Sun, the playwright Lorraine Hansberry depicts the life of an impoverished African American family living on the south side of Chicago. The Youngers, living in a small apartment and having dreams larger than the world in which the live, often use verbal abuse as a way to vent their problems. Many times, this verbal abuse leads to unnecessary conflict within the family. The most frequently depicted conflict is that between WalterRead MoreLorraine Hansberry1192 Words   |  5 PagesLorraine Hansberrys A Raisin in the Sun The characters in Lorraine Hansberrys play are very significant in understanding the play. The characters are examples of they way Lorraine lived day by day her live when she was a kid. The success of the play was brought out by the characters and her way of keeping our interest with each one of them. They characters are very critical in understanding the play. There were four main characters that made the play a sellout, Lena, Ruth, Beneatha and WalterRead MoreCharacters in Raisin in the Sun Essay876 Words   |  4 PagesCharacters in Raisin in the Sun The characters in Lorraine Hansberry^s play are very significant in understanding the play. The characters are examples of they way Lorraine lived day by day her live when she was a kid. The success of the play was brought out by the characters and her way of keeping our interest with each one of them. They characters are very critical in understanding the play. There were four main characters that made the play a sellout, Lena, Ruth, Beneatha and WalterRead More Racism and the American Dream in Hansberry’s A Raisin in the Sun1340 Words   |  6 PagesA Raisin in the Sun is written by a famous African- American play write, Lorraine Hansberry, in 1959. It was a first play written by a black woman and directed by a black man, Lloyd Richards, on Broadway in New York. The story of A Raisin in the Sun is based on Lorraine Hansberry’s own early life experiences, from which she and her whole family had to suffer, in Chicago. Hansberry’s father, Carol Hansberry, also fought a legal battle against a racial restrictive covenant that attempted to stop African-Read MoreRacial Identity in A Raisin in the Sun: Who Am I?1102 Words   |  5 Pages Growing up as a child during the 1970s in a predominantly African American neighborhood of South Central Los Angeles, the differences between me and my playmates never occurred to me. Although my mother and I eventually moved to the suburbs, my father remained there well into my adulthood. However, it was not until late childhood, while visiting my father on weekends, that I started to differentiate between my friends and myself, and my father’s home and my home. The realization I was different

Memories of Life Before Government Control Orwells 1984,...

Overbearing governments can change every aspect of society but people’s memories and their stories of the past cannot be completely altered to forget what life was like. Society uses these memoires to compare it to the new way of ruling which sometimes is less favorable to the individual. Governments try to change people’s opinions of reality which proves to be impossible. Within the novels, 1984 by George Orwell, The Handmaids Tale by Margaret Atwood and Brave New World by Aldous Huxley the Governments have taken societys freedom away and all that remains are the memories of what life was like before the changes; the main characters are constantly using the past as a way to survive through the difficult times. Winston in 1984 uses his†¦show more content†¦Winston has trouble keeping straight the real facts because they have been clouded over by so many changes in history made instantly by Big Brother. The common citizens do not even notice when history is altered right before their eyes. During a protest the country of interest changes from Eurasia to Eastasia. The change is seamlessly made as the crowed does not even flinch. Winston notices and tries to convince Julia, his lover that the war was really with Eurasia and not Eastasia. He argued with her about it for perhaps a quarter of an hour. In the end he succeeded in forcing her memory back until she did dimly recall that at one time Eastasia and not Eurasia had been the enemy. But the issue still struck her as unimportant(Orwell 154). This issue was so important to Winston because he wanted to spread his knowledge of the lies of Big Brother. He believed if people could just remember what life was like before Big Brother there was still hope of overthrowing the government. Winston knew, When memory failed and written records were falsified—when that happened, the claim of the Party to have improved the conditions of hu man life had got to be accepted, because there did not exist, and never again could exist, any standard against which it could be tested. (Orwell) A persons memory of better times gives hope that things will return to the way they used to be. Offred, the main character in The Handmaids Tale, is constantly

Steel Design Free Essays

string(213) " method for determining the elastic critical moment for lateraltorsional buckling Mcr !!!!!!!! May use ‘LTBeam’ software \(can be downloaded from CTICM \?\?\?\?\?\? website\) Or may use method presented by L\." STEEL BEAM DESIGN Laterally Unrestrained Beam Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 1 Non-dimensional slenderness Beam behaviour analogous to yielding/buckling of columns. M Wyfy Material yielding (in-plane bending) MEd MEd Elastic member buckling Mcr Lcr 1. We will write a custom essay sample on Steel Design or any similar topic only for you Order Now 0 Dr. A Aziz Saim 2010 EC3 Non-dimensional slenderness Unrestrained Beam ? LT 2 Lateral torsional buckling Lateral torsional buckling Lateral torsional buckling is the member buckling mode associated with slender beams loaded about their major axis, without continuous lateral restraint. If continuous lateral restraint is provided to the beam, then lateral torsional buckling will be prevented and failure will occur in another mode, generally in-plane bending (and/or shear). Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 3 Eurocode 3 Eurocode 3 states, as with BS 5950, that both crosssectional and member bending resistance must be verified: MEd ? Mc ,Rd Cross-section check (In-plane bending) MEd ? Mb,Rd Dr. A Aziz Saim 2010 EC3 Unrestrained Beam Member buckling check 4 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 5 Laterally Unrestrained Beam The design of beam in this Lecture 3 is considering beams in which either no lateral restraint or only intermittent lateral restraint is provided to the compression flange Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 6 Lateral Torsional Buckling Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 7 Lateral Torsional Buckling Figure 3-1 shows an unrestrained beam subjected to load increment. The compression flange unrestrained and beam is not stiff enough. There is a tendency for the beam to deform sideways and twist about the longitudinal axis. The failure mode which may occur to the beam is called lateral torsional buckling. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 8 ?Involves both deflection and twisting rotation ?Out-of plane buckling. Bending Resistance M c, Rd ? M pl ? W pl f y ?M0 Due to the effect of LTB, the bending resistance of cross section become less. Failure may occurs earlier then expected Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 9 Examples of Laterally Unrestrained Beam Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 10 Restrained Beam Comparsion Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 11 Intermittent Lateral Restrained Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 12 Torsional restraint Usually both flanges are held in their relative positions by external members during bending. May be provided by load bearing stiffeners or provision of adequate end connection details. See Figure 3-4. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 13 Beam without torsional restraint Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 14 Can be discounted when: †¢ Minor axis bending †¢ CHS, SHS, circular or square bar †¢ Fully laterally restrained beams †¢ ? LT 0. 2 (or 0. 4 in some cases) – Unrestrained length Cross-sectional shape End restrained condition The moment along the beam Loading – tension or compression Unrestrained Beam 16 Dr. A Aziz Saim 2010 EC3 Lateral torsional buckling resistance Checks should be carried out on all unrestrained segments of beams (between the points where lateral restraint exists). Lateral restraint Lateral restraint Lcr = 1. 0 L Lateral restraint Beam on plan Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 17 Three methods to check LTB in EC3: †¢ The primary method adopts the lateral torsional buckling curves given by equations 6. 56 and 6. 57, and is set out in clause 6. 3. 2. 2 (general case) and clause 6. 3. 2. 3 (for rolled sections and equivalent welded sections). The second is a simplified assessment method for beams with restraints in buildings, and is set out in clause 6. 3. 2. 4. †¢ The third is a general method for lateral and lateral torsional buckling of structural components, given in clause 6. 3. 4. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 18 Eurocode 3 states, as with BS 5950, that both cross-sectional and member bending resistance must be verified: MEd ? Mc ,Rd Cross-section check (In-plane bending) MEd ? Mb,Rd Dr. A Aziz Saim 2010 EC3 Unrestrained Beam Member buckling check 19 Lateral-torsional buckling Eurocode 3 design approach for lateral torsional buckling is analogous to the olumn buckling treatment. The design buckling resistance Mb,Rd of a laterally unrestrained beam (or segment of beam) should be taken as: Mb,Rd ? ?LT Wy fy ? M1 Reduction factor for LTB Lateral torsional buckling resistance: Mb,Rd = ?LT Wy fy ? M1 Equation (6. 55) Wy will be Wpl,y or Wel,y ?LT Dr. A Aziz Saim 2010 EC3 is the reduction factor for lateral torsional buckling Unrestrained Beam 21 Buckling curves – general case (Cl 6. 3. 2. 2) Lateral torsional buckling curves for the general case are given below : (as in Eq (6. 56)) ?LT ? 1 2 ? LT ? ?LT ? ?2 LT but ? LT ? 1. 0 ?LT ? 0. 5 [ 1 ? ?LT (? LT ? 0. ) ? ?2 ] LT Plateau length Imperfection factor from Table 6. 3 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 22 Imperfection factor ? LT Imperfection fact ors ? LT for 4 buckling curves: (refer Table 6. 3) Buckling curve Imperfection factor ? LT a 0. 21 b 0. 34 c 0. 49 d 0. 76 Buckling curve selection For the general case, refer to Table 6. 4: Cross-section Rolled I-sections Welded Isections Limits h/b ? 2 h/b 2 h/b ? 2 h/b 2 – Buckling curve a b c d d Other crosssections Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 24 LTB curves 4 buckling curves for LTB (a, b, c and d) 1. 2 Reduction factor ? LT . 0 0. 8 0. 6 0. 4 0. 2 0. 0 0 0. 5 1 1. 5 Curve a Curve b Curve c Curve d 2 2. 5 0. 2 Dr. A Aziz Saim 2010 EC3 Non-dimensional slenderness Unrestrained Beam ?LT 25 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 26 lateral torsional buckling slenderness ? LT Mcr ? Wy f y Mcr Elastic critical buckling moment Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 27 Non-dimensional slenderness †¢ Calculate lateral torsional buckling slenderness: ? LT ? Wy f y Mcr †¢ Buckling curves as for compression (except curve a0) †¢ Wy depends on se ction classification †¢ Mcr is the elastic critical LTB moment Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 28 BS EN 1993-1-1 does not give a method for determining the elastic critical moment for lateraltorsional buckling Mcr !!!!!!!! May use ‘LTBeam’ software (can be downloaded from CTICM website) Or may use method presented by L. You read "Steel Design" in category "Essay examples" Gardner †¦Ã¢â‚¬ ¦. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 29 Mcr under uniform moment For typical end conditions, and under uniform moment the elastic critical lateral torsional buckling moment Mcr is: Mcr ,0 G IT Iw Iz Lcr ? EIz ? 2 Lcr 2 ? Iw Lcr GIT ? ? ? 2 ? ? EIz ? ? Iz 2 0. 5 is the shear modulus is the torsion constant is the warping constant is the inor axis second moment of area is the buckling length of the beam Unrestrained Beam 30 Dr. A Aziz Saim 2010 EC3 Mcr under non-uniform moment Numerical solutions have been calculated for a number of other loading conditions. For uniform doubly-symmetric cross-sections, loaded through the shear centre at the level of the centroidal axis, and with the standard conditions of restraint described, Mcr may be calculated by: ? EIz Mcr ? C1 2 Lcr 2 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam ? Iw Lcr GIT ? ? ? 2 ? ? EIz ? ? Iz 2 0. 5 31 C1 factor – end moments For end moment loading C1 may be approximated by the equation below, though other approximations also exist. C1= 1. 88 – 1. 40y + 0. 52y2 but C1 ? 2. 70 where y is the ratio of the end moments (defined in the following table). Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 32 C1 factor – transverse loading Loading and support conditions Bending moment diagram Value of C1 1. 132 1. 285 1. 365 1. 565 1. 046 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 33 Design procedure for LTB Design procedure for LTB: 1. Determine BMD and SFD from design loads 2. Select section and determine geometry 3. Classify cross-section (Class 1, 2, 3 or 4) 4. Determine effective (buckling) length Lcr – depends on boundary conditions and load level 5. Calculate Mcr and Wyfy Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 34 Design procedure for LTB 6. Non-dimensional slenderness ? LT ? Wy fy Mcr 7. Determine imperfection factor ? LT 8. Calculate buckling reduction factor ? LT 9. Design buckling resistance 10. Check Mb,Rd ? ?LT Wy fy ? M1 MEd ? 1. 0 Mb,Rd for each unrestrained portion Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 35 LTB Example General arrangement Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 36 LTB Example Design loading is as follows: 425. 1 kN A B C 319. 6 kN D 2. 5 m 3. 2 m 5. 1 m Loading Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 37 LTB Example 267. 1 kN A B D 52. 5 kN SF C 477. 6 kN Shear force diagram B A C D BM 1194 kNm 1362 kNm Bending moment diagram Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 38 LTB Example For the purposes of this example, lateral torsional buckling curves for the general case will be utilised. Lateral torsional buckling checks to be carried out on segments BC and CD. By inspection, segment AB is not critical. Try 762? 267? 173 UB in grade S 275 steel. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 39 LTB Example b z tw h d y y r z tf h = 762. 2 mm b = 266. 7 mm tw = 14. 3 mm tf = 21. 6 mm r = 16. mm A = 22000 mm2 Wy,pl = 6198? 103 mm3 Iz = 68. 50? 106 mm4 It = 2670? 103 mm4 Iw = 9390? 109 mm6 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 40 LTB Example For a nominal material thickness (tf = 21. 6 mm and tw = 14. 3 mm) of between 16 mm and 40 mm the nominal values of yield strength fy for grade S 275 steel (to EN 10025-2) is 265 N/mm2. From cla use 3. 2. 6: N/mm2. E = 210000 N/mm2 and G ? 81000 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 41 LTB Example Cross-section classification (clause 5. 5. 2): e ? 235 / fy ? 235 / 265 ? 0. 94 Outstand flanges (Table 5. 2, sheet 2) cf = (b – tw – 2r) / 2 = 109. 7 mm cf / tf = 109. 7 / 21. 6 = 5. 8 Limit for Class 1 flange = 9e = 8. 48 5. 08 ? Flange is Class 1 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 42 LTB Example Web – internal part in bending (Table 5. 2, sheet 1) cw = h – 2tf – 2r = 686. 0 mm cw / tw= 686. 0 / 14. 3 = 48. 0 Limit for Class 1 web = 72 e = 67. 8 48. 0 ? Web is Class 1 Overall cross-section classification is therefore Class 1. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 43 LTB Example Bending resistance of cross-section (clause 6. 2. 5): Mc ,y,Rd ? Wpl,y fy ? M0 for Class 1 and 2 sec tions 6198 ? 103 ? 265 ? ? 1642 ? 106 Nmm 1. 0 ? 1642 kNm ? 1362 kNm ? Cross-section resistance in bending is OK. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 44 LTB Example Lateral torsional buckling check (clause 6. 3. 2. 2) – Segment BC: MEd ? 1362 kNm Mb ,Rd ? ? LT Wy fy ? M1 where Wy = Wpl,y for Class 1 and 2 sections Determine Mcr for segment BC (Lcr = 3200 mm) Dr. A Aziz Saim 2010 EC3 ? EIz Mcr ? C1 2 Lcr 2 ? Iw Lcr GIT ? ? ? 2 ? ? EIz ? ? Iz Unrestrained Beam 2 0. 5 45 LTB Example For end moment loading C1 may be approximated from: C1 = 1. 88 – 1. 40y + 0. 52y2 but C1 ? 2. 70 1194 y is the ratio of the end moments ? ? 0. 88 1362 ? C1 ? 1. 05 ? 2 ? 210000 ? 68. 5 ? 106 Mcr ? 1. 05 ? 32002 ? 9390 ? 109 32002 ? 81000 ? 2670 ? 103 ? ? ? 68. 5 ? 106 ? 2 ? 210000 ? 68. 5 ? 106 ? ? 0. 5 = 5699Ãâ€"106 Nmm = 5699 kNm Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 46 LTB Example Non-dimensional lateral torsional slenderness for segment BC: ? LT ? Wy fy Mcr 6198 ? 103 ? 265 ? ? 0. 54 6 5699 ? 10 Select buckling curve and imperfection factor ? LT: From Table 6. 4: h/b = 762. 2/266. 7 = 2. 8 5 For a rolled I-section with h/b 2, use buckling curve b Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 47 LTB Example From Table 6. 3 of EN 1993-1-1: For buckling curve b, ? LT = 0. 34 Calculate reduction factor for lateral torsional buckling, ? LT – Segment BC: ?LT ? 1 ? LT ? ? 2 LT LT but ? LT ? 1. 0 where ? LT ? 0. 5 [ 1 ? ?LT (? LT ? 0. 2) ? ?2 ] LT Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 48 LTB Example ?LT = 0. 5[1+0. 34(0. 54-0. 2) + 0. 542] = 0. 70 ? ? LT ? 1 0. 70 ? 0. 70 ? 0. 54 2 2 ? 0. 87 Lateral torsional buckling resistance Mb,Rd – Segment BC : Mb,Rd ? ? LT Wy fy ? M1 265 ? 0. 87 ? 6198 ? 10 ? 1 . 0 3 ? 1425 ? 106 Nmm ? 1425 kNm Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 49 LTB Example MEd 1362 ? ? 0. 96 ? 1. 0 ? Segment BC is OK Mb,Rd 1425 Lateral torsional buckling check (clause 6. 3. 2. 2) – Segment CD: MEd ? 1362 kNm Mb ,Rd ? ? LT Wy fy ? M1 where Wy = Wpl,y for Class 1 and 2 sections Determine Mcr for segment CD (Lcr = 5100 mm) Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 50 LTB Example ? EIz Mcr ? C1 2 Lcr 2 ? Iw Lcr GIT ? ? ? 2 ? Iz ? EIz ? ? 2 0. 5 Determine y from Table: 0 y is the ratio of the end moments ? ?0 1362 ? C1 ? 1. 88 ? 2 ? 210000 ? 68. 5 ? 106 Mcr ? 1. 88 51002 ? 9390 ? 109 51002 ? 81000 ? 2670 ? 103 ? ? ? ? 68. 5 ? 106 ? 2 ? 210000 ? 68. 5 ? 106 ? ? 0. 5 = 4311? 106 Nmm = 4311 kNm Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 51 LTB Example Non-dimensional lateral torsional slenderness for segment CD: ? LT ? Wy fy Mcr 6198 ? 103 ? 265 ? ? 0. 62 6 4311? 10 The buckling curve and imperfection factor ? LT are as for segment BC. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 52 LTB Example Calculate reduction factor for lateral torsional buckling, ? LT – Segment CD: ?LT ? 1 ? LT ? ? 2 LT 2 LT but ? LT ? 1. 0 where ? LT ? 0. 5 [ 1 ? ?LT (? LT ? 0. 2) ? ?2 ] LT = 0. 5[1+0. 34(0. 62-0. 2) + 0. 622] = 0. 76 ? ? LT Dr. A Aziz Saim 2010 EC3 ? 1 0. 76 ? 0. 76 ? 0. 62 2 Unrestrained Beam 2 ? 0. 83 53 LTB Example Lateral torsional buckling resistance Mb,Rd – Segment CD : Mb,Rd ? ?LT Wy fy ? M1 265 ? 0. 83 ? 6198 ? 10 ? 1. 0 3 ? 1360 ? 106 Nmm ? 1360 kNm MEd 1362 ? ? 1. 00 Mb,Rd 1360 Segment CD is critical and marginally fails LTB check. Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 54 Blank Page Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 55 Simplified assessment of ? LT For hot-rolled doubly symmetric I and H sections without destabilising loads,? may be conservatively simplified to: LT ? LT ? 1 0. 9 ? z ? C1 ?z 1 0. 9 ? 1 C1 E ? z ? L / iz ; ? 1 ? ? fy As a further simplification, C1 may also be conservatively taken = 1. 0. Simplified assessment of ? LT Substituting in numerical values for simplified expressions result. ? 1 , the following S235 ? LT ? 1 L / iz C1 104 S275 ? LT ? 1 L / iz C1 96 S355 ? LT ? 1 L / iz C1 85 C1 may be conservatively taken = 1. , though the level of conservatism increases the more the actual bending moment diagram differs from uniform moment. Simplified method (Cl. 6. 3. 2. 4) Simplified method for beams with restraints in buildings (Clause 6. 3. 2. 4) This method treats the compression flange of the beam and part of the web as a strut: b b Compression h Tension Compression flange + 1/3 of the compressed area of web Strut Dr. A Aziz Saim 2010 EC3 Beam Unrestrained Beam 58 General method (Cl. 6. 3. 4) General method for lateral and lateral torsional buckling of structural components †¢ May be applied to single members, plane frames etc. Requires determination of plastic and elastic (buckling) resistance of structure, which subsequently defines global slenderness †¢ Generally requires FE Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 59 Blank Page Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 60 Important Notes: (End Connections) When full torsional restraint exist: -both the compression and tension flanges are fully restrained against rotation on plan -both flanges are partially restrained against rotation on plan – both flanges are free to rotate on plan Unrestrained Beam 61 Dr. A Aziz Saim 2010 EC3 Connection Detail Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 62 Important Notes: (End Connections) Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 63 Important Notes: (End Connections) When both flanges are free to rotate on plan and the compression flange is unrestrained: i. torsional restraint is provided solely by connection of the tension flange to the supports, ii. torsional restraint is provided solely by dead bearing of the tension flange on support. Unrestrained Beam 64 Dr. A Aziz Saim 2010 EC3 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 65 Dr. A Aziz Saim 2010 EC3 Unrestrained Beam 66 How to cite Steel Design, Essay examples