Design of a steel skew cantilever followed by construction and testing to destruction Free Essays

Design of a steel skew cantilever followed by construction and testing to destruction. Analysis and improvements section included. Aiming for minimum weight and structural costs, while achieving a working load of 1kN and a failure load of 2kN. We will write a custom essay sample on Design of a steel skew cantilever followed by construction and testing to destruction or any similar topic only for you Order Now Statement of the Problem: To design and build a steel skew cantilever that is required to show no visible deformation at a vertical working load of 1000N and to fail at 2000N. The objective is to design a structure that satisfies the loading conditions, while keeping weight to a minimum and maintaining design simplicity; to reduce drawing and fabrication time, and making the structure more predictable through analysis. The load is at a horizontal distance of 815mm from a rigid vertical plate. The line of action of the load is 407mm to the right of the normal to the wall through the centre of the main plate when viewed from the front of the main plate. The load is applied through a rig with a 13mm diameter bolt. The main plate has 4 pairs of M6 tapped holes to which the structure may be attached. Designs Considered: The main design considered apart from the 4 main member triangulated cantilever, was based around a 3 main member design with cross bracing shown in the diagram to the right. The advantage of this structure is a reduction in weight, holes and rivets thus a huge reduction in cost. However, the design that we came up with was too difficult to analyse and predict during in failure, due to the side planes not being vertical. Also, construction would have been quite difficult because all cross braces would have to attach to the main members at an angle, thus additional plates would have be constructed which would have raised the price dramatically. The other design considered was based on the 4 main member design but flipped upside down. However, this would mean that the compression member would be comparatively long, increasing the need for cross bracing due to potential buckling. Thus the structure would be no better than the one we have selected only it would cost more due to the additional cross bracing. The box design was considered, however, it is not very suitable for a skew cantilever as construction would be immensely hard. Design considerations: The rig to which the structure was to be attached was inspected to see whether the load plate would fit and to get a general feel for the vertical constraints of the jack. To prevent a bending moment within the structure, lines of actions of forces in members must cross at a point. Hence in the drawings, lines of actions for every joint are shown to meet at a point within the material. For single cross braces, this line of action is 3/4 of the way in from the edge parallel with the edge. To make members act as though they were in mode B, the struts had to be rivet together. This was done 40mm from the edges of the struts in question and subsequently the remaining length was divided up into 3 sections at which the boundary of each division was riveted. This was performed on all the double angled struts. Where possible, the struts coming into connecting plates were made to touch the plate with their edge so that they would be transferring their load in a more direct manner. We attempted to make the base as wide as possible, for stability hence the connecting plates should go up to the edge of the main plate. Construction Phase: The base was the first thing to be constructed as it was easier than the upper members, thus by the time it had been built, experience had been gained and could applied to a more complex construction step (the upper members). The upper members were then constructed and both sets were fitted to the base plate. An additional plate was put in between the connecting plate and the main plate for the tension members to prevent the bolts from tearing out. The partially completed structure was taken to the measurement deck, where the alignment was checked. It was within 5mm in respect to the horizontal plane, thus we could slightly bias connections so that the alignment became closer to about 3mm. It was then noted that the rig that would connect the load to the load plate needed the load plate to have parallel edges, thus a double bend and an extension of 40mm in the load plate was required to allowed the rig to connect to the load plate. See right hand page for diagram. The load plate was then attached and the structure was checked that it aligned to about 3mm. The cross braces were than fabricated and attached. An attempt was made to work efficiently during construction, my laboratory partner and I finished with 6 hours to spare. Modifications: To M4 bolts were used to help keep the two sections of the load plate in alignment to achieve ease of rig attachment. These are attached as shown on the diagram to the right. A small cross brace was also placed between the two tension members at the top to attempt to prevent rotation of the structure. See right for the diagram. Also there was not enough space for the smallest cross brace connecting the compression members, thus it was not included. Some minor changes in the lengths of some of the members was required to improve alignment. Also some edges of struts had to be cut so that they could rest flat against others to transfer load more effectively. Cost and Mass of Structure: The mass was 2.52kg, which is heavy in comparison to the other groups, but not the heaviest. The material cost was 120.5 and the labour cost was 282 giving a total of 452.5, once again the cost ranked high amongst the other groups. However, considering the magnitude of the mass, if the cost saving strategies had not been applied then the cost would have been about 30 higher. These cost saving techniques consisted of using a hole to not only mount the members to connecting sheet metal but also a cross brace, thus saving a rivet, a hole and some time during fabrication. Depending on the forces, this technique could be slight disadvantage, the joint would now be in double sheer, and the rivet would be under greater loading. However, this effect would be small due to the small forces in the cross braces. Test results and Observations: The structure had a very slight amount of visible deformation at the working load of 1kN, and finally failed at 2.57kN. This was mainly due to the rightmost (looking at the front plate) compression member 5 buckling inwards at a position closer to the wall than the intersection between member 10 and 11. Another noted deformation was that the metal plates (A and B) connecting the main plate to the compression members had been bent inwards towards the main plate as the corners of the A and B were not touching the main plate. This meant that as the compression force in member 10 and 11 grew the force on the corner increased and cause deformation of the connecting plate. If the buckling in the compression member had not occurred, it would be conceivable that this would be the next location for failure. Suggested Modifications to Improve Performance: Using another cross brace in a sense parallel to the main plate between the lower main compression members 10 and 11 would have prevented the buckling that caused the main failure from occurring. The geometry of the proposed cross brace would force the member to become stockier thus its critical stress would be much higher, allowing us to once again us mode A with a 9.5mm by 9.5mm of thickness 0.8mm. If the holes for the bent plates that connects the main compression members 3 and 5 to the main plate were moved such that the corner of the connecting plate lay within the normal of the edge of the main plate, then this would reduce deformation of the connecting plate and hence the structure. If these connecting bent plates were to be the first point of failure, the modifications described would increase the failure load by postponing the tearing of the connecting plates. Conclusions: The main failure as discussed was mode B buckling of the longest compression member due to insufficient cross bracing. It would be interesting to rebuild the cantilever with the improvements and even have an entire redesign. One can learn many things from analyzing a failure. For example how to improve the structure and more importantly how to go about design in the first place. How to cite Design of a steel skew cantilever followed by construction and testing to destruction, Papers

hamlet, edgar sawtelle contrast Essay Example For Students

hamlet, edgar sawtelle contrast Essay Brittany Travers MS. OBrien English IV 18 January 2013 Comparative Essay In the drama of Hamlet and the novel The Story of Edgar Sawtelle there are many similarities. One of the most interesting similarities being, the relationship between Hamlet and Horatio, and Edgar and Almondine. They both reflect on the loyalty, protection and support shown in each writing. In Shakespeares drama Hamlet, Horatio and Hamlet have been best friends since there childhood years and have been ever since. In Wroblewskis novel, The Story of Edgar Sawtelle, Edgar and Almondine have been inseparable since the birth of Edgar, with the locality of Edgar being born mute. All of which are displayed in the novel The Story of Edgar Sawtelle, and the drama Hamlet. In the drama Hamlet, Horatios loyalty is rock-steady throughout the play. So much that he is Hamlets only true confidant. Horatio, being Hamlets one and only best friend is the one to tell him that the watchmen have seen a ghost resembling his father. After revealing the news to Hamlet they then go together to see the ghost and are sworn to secrecy about the ghosts appearance. This is one situation in the drama f Hamlet where loyalty is displayed. In Wroblewskis novel, loyalty is shown through the communication of Edgar and Almondine. Knowing Edgar is disabled, Almondine is trained to help him find a way of communicating. With Edgar being born mute, they speak through what is called sign. This shows his loyalty through Almondine sticking by his side. In the scene of the fght with Hamlet and Laertes, Horatio warns Hamlet not to take part in the friendly duel that Claudius and Laertes have arranged. By telling Hamlet this, Horatio is looking out for his best interest and trying to keep both of them safe. Also in the tragedy Hamlet, the bond with both friends is shown in the plays ending. Horatio offers to commit suicide when his beloved Hamlet is dying before him. Hamlet insists, however, Horatio lives to tell the tragic story, and he does so. This is the upmost way of showing Horatios protective instinct for his best friend Hamlet. During The Story of Edgar Sawtelle, Almondine also shows his loyalty through the findings of Edgar after he leaves to the Chaquemegon Forest. Usually dogs will lie around and die of a broken heart, but Almondine, a dog with some degree of hope about the world ends up looking around. Almondine chooses the latter. She begins to search, not Just for Edgar but for a solution to the whole dilemma of being without Edgar, about being separated from ones purpose in life, to help him communicate. This is something larger and more intelligent than physical separation. A question that Edgar himself happens to encounter with at that moment. In conclusion, there are many similarities in both the novel The Story of Edgar Sawtelle and the drama Hamlet with the comparison of loyalty between Edgar and Almondine, and Horatio and Hamlet. hamlet, edgar sawtelle contrast By btraversl 5

The Darwinism theory in the text The Island of Dr Moreau

The Darwinism theory talks about evolution or better still the transmutation of species. This entails the transformation of various species from their original form to a lot more different forms through what is commonly called genetic transformation.Advertising We will write a custom essay sample on The Darwinism theory in the text The Island of Dr Moreau specifically for you for only $16.05 $11/page Learn More This simply means that the present existing organisms descended from somewhere and therefore there is a difference between the organisms that existed millions of years ago and those that are in existence as of now. For instance man is thought to trace his roots from the ape family of organisms and therefore it is thought by those who share in the Darwinism theory that evolution must have taken place. Likewise in the text The Island of Dr Moreau, we encounter the doctor, who we learn is a runaway vivisectionist from London for many years now. He, t he doctor has made beast men, who are half men and half beasts, (Wells 18)therefore he can be considered to have caused a sort of evolution from one form of organism to another and that is, he created half beasts and half human beings by mixing genes from both animals and human beings. The Darwinism theory is evident throughout the book as we encounter a certain class of organisms referred to as beast men. These beast men are an absolute mockery of man. Prendick happens to see the difference that exists between the beast men and real men through their character because their character is very weird and different in comparison to humans they seem to be unruly and very noisy (Wells 24). Their physical appearance is described by Prendick as â€Å"inhuman- looking humans (Wells 30)†. Their exists many of them, that is the Leopard Man, Ape Man, Bull Men and many more forms. This therefore means that the animals’ physical appearance could be half beast and half human. Moreau ’s experiments have borne fruits that can be seen as a form of evolution from one set of organisms to another.  Darwinism propagates the idea of the formation or rather the development of life from nothing. When organisms come up and grow from one stage to another then that can be regarded as the propagation of that theory, now that beast men are in existence and who knew that there could be a common means of communication that cuts across the group, because all these beast men can talk to each other by use of rudimentary language and understand each other by mere fact that they have got a humanistic characteristic that cuts across, therefore genetic mutations must have really occurred in doctor Moreau’s experiments.Advertising Looking for essay on british literature? Let's see if we can help you! Get your first paper with 15% OFF Learn More We are told that they can also work as servants, chant their songs and do many more activities. It is well unders tood that animals can never be servants and do chores that are designed by men. The doctor’s overpowering desire to bring about scientific progression is what causes him to carry out the experiments. This he thought was to bring about a sense of making man or even the beasts more efficient and better than their former selves. He believes that pain and pleasure are not relevant thereby having to do what he does in order to achieve his goals in as much as society does not approve of it (Wilson 54). Moreau wants to bring change that is to be reckoned. The race of sub humans that he intends to create are expected to be superior to the existing man. With their action of rebellion towards Moreau and Montgomery, the beast men depict clear humanistic characteristic among them, rebellion towards tyranny. But to what extent is the story about the possible existence of the beast people true? This can be left to the theoreticians of Darwinism to justify that. At some point we meet Montgo mery saying that the beast people†Ã¢â‚¬ ¦Ã¢â‚¬ ¦.actually bore off springs, but that these generally died. There was no evidence of the inheritance of the acquired human characteristics (Well 61)†. But all the same evolution can be seen to be put to test by Wells in this intriguing and entertaining, though scary text. By bringing the beast men with distinctively common characteristics though each belonging to a different species, one can be sure that science plays a major role in literature because it brings out exciting ideas in prose ( Wilson 54). Works Cited Wells, Herbert. Science Fiction. United Kingdom. Stone Kimball. 1896. pp. 60 – 209. Wilson, David. Evolution for Everyone: How’s Darwin’s Theory Can Change the Way We Think about Our Lives. Delacorte Press. 2007. pp. 70 – 345.Advertising We will write a custom essay sample on The Darwinism theory in the text The Island of Dr Moreau specifically for you for only $16.05 $1 1/page Learn More This essay on The Darwinism theory in the text The Island of Dr Moreau was written and submitted by user Happy Hogan to help you with your own studies. You are free to use it for research and reference purposes in order to write your own paper; however, you must cite it accordingly. You can donate your paper here.

What Would Your Job Be Like If It Were in the 1700s

What Would Your Job Be Like If It Were in the 1700s With 200+ years of innovations and changes since July 4th, 1776, some of the same jobs were  just as important then as they are today.   Let’s take a look at how they have changed since the United States of America declared its independence. HealthcareDuring the Revolutionary War effort, nurses were in high demand for the military to mend the sick and wounded,  earning 2 to 4 dollars per month.   Today, with the U.S. healthcare industry nearing $3 trillion and integrating with modern  innovations in technology,  a myriad of opportunities continue to grow in healthcare.   While specialized education is often required, competitive salaries follow those who pursue it.PublishingJohn Campbell brought us  The Boston News-Letter in  1704,  the colonies’ second paper which lasted 72 years.   Same as today, nearly every town in colonial times strove to have a homegrown publication.   The internet has completely revolutionized news media  with an ever gr owing number of devices and publication mediums, and in some cases, completely free and available to the public.ManufacturingOn the cusp of the industrial revolution, the American colonies began with simple textiles and hand looms to what would today become the world’s second largest global manufacturer.   Some of the top manufacturing sectors in the U.S. currently include chemical, machinery and energy.ConstructionDuring colonial times, ship building was a large sector for carpenters and builders.   Homes and buildings used primarily brick, wood and stucco.   Today, the construction industry in the U.S. employs over 7 million workers in commercial, residential, aerial and naval sectors and showing steady growth since 2008.Finance  The Continental U.S. largely financed the Revolutionary War through loans from the French government and other foreign allies, leaving control to the political elite of the Continental Congress.   Today, the complex finance industry repre sents nearly 8% of U.S. GDP, with leaders headquartered  in cities like Charlotte, Atlanta, Omaha and Minneapolis.  FarmingAlways an integral part of American industries, farming was just as important then as it is now.   Most Americans during the westward expansions had farms to support their families and service small local markets.   Today, American agriculture is a $70 billion industry expanding across the country and serving to feed the  entire globe.

Democracy in China Essay Example | Topics and Well Written Essays - 1500 words

Democracy in China - Essay Example As Chinese 'media' and 'democracy' are interlinked in a single framework, people expects from media to wake up democracy in China, not the vice versa. It is through the wide contribution of picky media that today has made it possible to at least speak in favour of self-contained civil societies and public spheres in China. With these issues unresolved, and with market economics and representative democracy only partially institutionalised, Chinese Government has detected that socialism and fascism in today's era would not be taken as alternative models for modern society. A society which is media driven and can be scanned as long as it is 'Chinese local media'. But to the extent where Chinese Government enters the boundaries of International scrutiny, capitalist democracy in both the economic and political spheres is unable to acquire superiority. However, the efforts on part of the Government could be on its way showing fascism along with its military failure and all the inefficiencies of state socialism and authoritarian tendencies can be put in the court of Chinese Government. Media currently is playing hide and seek with the Chinese democracy where on seeking any possibility of democratic revival, International media would consider it a genius. ... y which has opened some new ways for building up a better image of democracy among the International media relations, International Media can help in protesting to social inequalities. Since this issue is the main obstruction in reviving a democratic China, therefore media can juxtapose 'social construction' in awakening democracy. These inequalities require a foreign body to predict reality on the basis of racial differences (Vhang et al, 1998). The foreign media can utilise this little opportunity from behalf of the Chinese government to make the Chinese public understand the responsibility to deliver a 'new' generation. A generation free from social inequalities and injustice. This would serve as the first step towards a democratic Government. International media can turn Chinese educational centers into 'revolutionary centers' as long as differences exists between yellow race and Koreans and Chinese who pour into schools from deprived and shabby homes quickly amaze with their high IQ scores. Such a social construction would serve as an injection at the ground root level where media would not only infuse equality among the public which would ultimately lead to democratise China but also would be helpful to develop a society where there would be no hard and fast social class differences among the citizenry. This message of equality from the international media would change the thinking of at least the younger generation, and on the basis of such equality democracy would be strengthened in China. From the local community 'town meetings', to the media of discussion and questioning, when all the racial and social differences would be alleviated the outcome would be finally into the great halls of the legislatures, the courts , the executive departments for prudent

Peer Review Essay Example | Topics and Well Written Essays - 1250 words

Peer Review - Essay Example With this, the consequence is viewed not as a private issue but as a global issue that ought to be taken up by all well meaning advocates of human rights. The writer suggests an action-driven solution in the sense that the writer wants to see the transportation of segregated students to White schools, where they can learn about the culture of other people and how to socialize easily with these people. The argument in favor of the solution is however weak as the writer does not give any legislative backing to the solution. The writer uses variety of research sources including court cases on the issue of segregation. There has also been sufficient analysis of the evidence. However, the analysis of sources would have been more proactive if primary sources were also used. The writer links the thesis or main argument directly to the consequences of poor education in the country; stating that the nation would have to build more schools if attention is not given to proper education. Given the prompt, the writer makes direct reference to it and tags segregation as a poor educational policy that is recipe for a degenerated society. Having tagged segregation as a bad educational policy, the writer goes ahead to clearly elaborate the consequences of segregation, stating that it could be a reason for moral breakdown in society. The reason for this argument was fused in the believe that when people are segregated one from another, they do not come to accept the personality of other people and as such have no inner regrets when they are offending them. The writer suggests a solution that is based on personal appeal to affected people. For this reason, the writer holds the believe that programs like Magnet Program can be used to attract and appeal to students in segregated schools to get attracted to their colleagues in other integrated schools. The writer argues in favor of the solution by drawing on

Global warming Essay Example | Topics and Well Written Essays - 750 words - 8

Global warming - Essay Example (1). The term global warming does not merely connote to an increase in the temperature but also envisages an overall climatic change. Because of this change in temperature and climate, economy, human health, and the ecosystems can encounter drastic consequences. The main pollutant to atmosphere that contributes to global warming is carbon dioxide, which causes warming in atmosphere. Other pollutants such as fossil fuel, methane gas and green house gases also are act as warming agents. Unfortunately, human beings are the ones who cause this imbalance between life and earth and the consequences have already reached disastrous proportions. CO2 emitted from â€Å"power plants and vehicles† play a crucial role in increasing CO2 concentration in the atmosphere (Wang & Chameides 36). Certain other human activities that entail degradation of wild life, â€Å"spread of homes and infrastructure† and sinking of costal land also adds pace to the process of global warming (Wang & Chameides 36). Global warming triggers killer heat waves, drought, forest pests, wildfires and contributes to rising sea level, shrinking snowpack, disappearance of glaciers, disintegrating polar ice, melting permafrost damage to coral reefs, shifting species rang es and yearly cycles and disease outbreaks (36). Besides, it also causes considerable harm to the ecosystem apart fro damaging agriculture and animal habitats. In addition, increase in atmospheric temperature may result in death of life forms, including human beings, due to the unbearable heat and drought. Wild fires can cause loss in â€Å"forestry, agriculture, and electric power sectors† (Wang & Chameides 36). High rates of evaporation may result in an increase in water vapor in air, which can cause heavy rainfall and flooding. Intense evaporation may also entail loss of moisture from soil and consequently droughts can occur (36). Evidence further points to the fact that over the course of 20th century, sea level has