Abstract of Finding the force in truss members by using the methods of joints and methods of selection

From this lab report the students are going to learn about the force in truss member by using the two methods in mechanical works that are method of selection and the other one is method of selection. Through the use of these two methods the students can easily specify how to use these methods and what the practical applications of these two methods are and the students will able to learn all the applications related to these two methods. In the introduction the students are able to learn about what these two methods are and how to apply force in truss and how to calculate the truss through these methods. Then after this the students will able to see what the main applications of these methods and how to calculate methods of selection and also method of joint. The test procedure is very important for this lab report because all the results and figures are based on these; also the students are able to perform the practical experiment and then after this they are able to calculate the important results to find the value of these two forces.

Motivation of Finding the force in truss members by using the methods of joints and methods of selection

Truss drives their strength from rectangle, triangle and square. But the square truss is not too much strong as compared with the triangle because of its unique structure and also the shape. This triangle shape is so much important because in the all the three forces at without touching the centre and all the weights is applied on its side and that is why most of the bridges are in the triangular shape and so that the total force applied and can be contributed easily on all sides. Also on of the most important advantage of using the truss triangle shape is that it is cost effective and save a lot of money when you design the shape for the bridge. Also one of the major advantage for using this design is that it saves the important time of the workers so that the easily complete the bridge. Also there is very less number of skills required to install the truss triangle because it is very easy to install.

Scope of Finding the force in truss members by using the methods of joints and methods of selection

There is a huge scope for the country how uses the truss and so that they can easily able to design bridges and other things from this. The best scope is for the architecture because he can easily able to apply his idea in designing which makes the bridge attractive and innovative and the person who can able to handle the construction design documents that is can able to make the drawing on the software. The next scope for the contractors, because truss designs are easy to be install so that by using these software drawings the contractors able to calculate how much construction material is required for the construction. Truss layout design makers there is also a huge scope so that they can able to design these drawings for the truss.

For the approach of truss the enginners use the direct stiffness method. This method is a matrix method in which the students can easily able to compute the member forces and also the displacement in different structures this method is also a finite element method. But regarding the prospective of this report the students use the method of section and the method of joints so they can easily able to apply these methods.

These results show that the triangular shape for the truss is the most suitable and the students can easily able to apply these two methods. The method of selection and the other one is the method of joint.

Introduction of Finding the force in truss members by using the methods of joints and methods of selectio

These trusses are mainly used in the structural engineering application for the mechanical engineer. One of the most important advantages is that the engineers can able to make huge structures by using very low amount of material means that these trusses covers large area by using minimum amount of the materials. In this section of the experiment the students are able to know about the planer truss in detail and also able to know how to apply these two methods to calculate the planer truss easily in quite effective manner.

First of all the student able to know about the planer truss, a planner truss has only three reaction forces that are unknown and in this experiment the students can able to apply basic skills to calculate these three unknown reaction forces. The students are able to calculate these unknown forces by using the method of joints. This particular method helps the students to easily calculate the unknown forces for the planer truss. This truss can be assumed as the comprise members that are jointed with each other by means of pin point.

This truss can be easily defined as it is composed of a straight slender member that may be pinned, or may be hanged or sometime may be weld to a pin point and forms a rigid structure.  The member of the truss are perfectly straight if they are not fully straight so means that they are unable to support any kind of force acting on these materials. The loads are applied of the joints so that these joints must be completely weld and hanged properly so that equal force can be act easily on each of the joint. All the joints must be frictionless because when there is force act on them so that these joints applies flexibility and also able to maintain the same position as the bridge has to.  There are three types of truss and that includes howe truss, pratt truss, warren truss. And for the lab report the students will work on the pratt truss in which the structure will be in very suitable form and comparatively less materials are used.

The truss can be used in some of the following application that includes, through this many of the bridges are designed, used to make railways station platforms, also through the use of truss able to make the roofs for different factories, truss applications also applies to make the garage sheds for different parking places, because of its stiffness and flexibility this can easily been used to make the transmission towers and also some of the important applications in making the sport stadium designs and also for making the cranes. There are two types of connections are used for the truss that includes the Pinned Connection and the next one is the Gusset plate connection.

There is also some of the load on the truss that includes the dead load, live load, wind load, weight of the roof and the last load is reactions at the support. These all loads are so much important and these loads must have to be considered before making the design for the truss. There are two methods to calculate the truss and this is also the main discussion of this lab report.           

Theory section of Finding the force in truss members by using the methods of joints and methods of selection

 In the structural engineering and for the architecture this truss is a structure that is comprise on the triangular structures that can be more than one and also they are constructed with the same straight members because the straight members can easily able to support. These straight members are then connected with the joints that are termed as the nodes all the external and internal forces and reactions are occurred on the node of the truss so that these nodes must be properly linked with each other so that they can able to support the triangular shape very easily. These forces that are acting on them can be considered as the tensile and maybe sometimes the comprehensive forces. All the moments and torques are not included because these forces are not being considered as the rotatory as well as the other reason is that these all the joints are considered as the revaluates.

There are some of the characteristics of truss that includes, the load must be axial will be considered because these loads are more flexible and there will be very low damage to the bridge. The other characteristic is that the load must be applied on the end points only because if the load acts on the middle so this means that the proper stiffness of the body will be less and it is become so much difficult to handle the bridge. So, on the basis of characteristic the load must be applied on the end point in that case the end points must be perfectly welded and hanged also. The last characteristic of truss is that all the elements of the material must be joined by the pins because it will increase the power of that design. There are some of the application of truss that includes, through this many of the bridges are designed, used to make railways station platforms, also through the use of truss able to make the roofs for different factories, truss applications also applies to make the garage sheds for different parking places, because of its stiffness and flexibility this can easily been used to make the transmission towers and also some of the important applications in making the sport stadium designs and also for making the cranes. Some of the important designs of the truss that is very much important in designing the different architecture designs and that include the following; open plane design, storage design, assymetric  design , double bobtail, a frame and purlin beam design, queen post design, extended tie design and the last one  warren design.

Planer trusses of Finding the force in truss members by using the methods of joints and methods of selection

These type of trusses lies on the single plane and they are often used to support the roofs and also all kind of bridges. Through the use of series of purlins, for the roof trusses the load of the roof is transmitted to the joints. As everyone knows that the plane supports the structure of two dimensions and on the other hand the roller only able to support the one direction.

Method of section of Finding the force in truss members by using the methods of joints and methods of selection

This method is used to find the unknown forces that are acting on the members of truss and this method involves the breaking of truss into its parts so that each member of the truss can be analysed easily.

Method of joints of Finding the force in truss members by using the methods of joints and methods of selection

This particular method is also used to calculate all the unknown forces that are acting on the members of truss, but in this method all the joints of the truss are centred and then it can be calculated easily and this is also one of the easiest way to calculate the unknown forces acting on the truss.

Test Procedure of Finding the force in truss members by using the methods of joints and methods of selection

In the test procedure the students will learn how to calculate the trusses by using these methods and also how to apply these two methods for the calculation of the trusses. For the calculations the students’ needs to perform experiment and then through this they will get some of the values and then they will able to calculate the unknown forces.

There are some of the equipment that are used to perform this experiment and that includes structure test frame, truss with strain gages, digital force display, load cell, digital strain display, two power supplies for the digital forces display and the strain display, callipers and the last one is the level indicator.

Procedure of Finding the force in truss members by using the methods of joints and methods of selection

 First of all measure the truss dimensions and also the member diameter and then record the strain gauge numbers that corresponds to each member. Then after this calculate the member forces and that is acting downward which is p= 100N, and the load acts on the joint, then after this calculate the strain in each member and this will help you to check the experimental data which is then measured later.

Then after this the students has to connect the power supplies which is then connected to the force display and then after this will display the strain and the students has to make sure that it is on and then after that the students has to leave the system for five minutes and this will help it to warm up and reach it to the steady state. Now after this the students has to adjust the load screw, this will make sure that the truss is at level position and then after this turn the knob on the load cell and make it sure that the load reading is touching the zero mark.  Then after this the students have to record all these values that is applied for each case and member that is P=0 and then move the load increase screw so that the load will be increase and then after this record the strain values and this is done for the each member. The load must not be exceeded from 500N. Then after this use the load screw to decrease the value of load up to zero. Now unplugged the supplies and calculate the theoretical values.

Steps to calculate truss from method of joints

Firstly the students need to calculate all the reactions at the supports, then after this they need to consider only one support first.  After calculate the first support then move to the other support, then after this again move on the other joint and in the last you need to add all the forces so that the forces on truss can be calculated.

Methods to calculate truss from method of section

In this the first step is the same like in the method of joints but then after this the student need to make a cut along the member of interest and after this calculate each of the section one by one and then  in the last add the final value so the truss has been calculated.

Results of Finding the force in truss members by using the methods of joints and methods of selection

These are the results after the calculation has been done and then after this using the method of section and also method of joints the students has calculated the values of these trusses. This is the main diagram on which this experiment has been performed.

Discussion and conclusion of Finding the force in truss members by using the methods of joints and methods of selection

From the whole report the students are able to perform the experiment to calculate the value of trusses and also able to calculate the truss member value theoretically through the use of method of sections and also the method of joints. Some of the facts and theories are also been seen about the trusses that how much the truss is important to design the biggest structures like the stadiums and the transmission towers.  Also see some of the characteristic of truss means that how the truss behave, the structure must be axial and the other characteristic is that all the forces are acting on the joint point which is supported by means of pin point. The member of the truss are perfectly straight if they are not fully straight so means that they are unable to support any kind of force acting on these materials. The loads are applied of the joints so that these joints must be completely weld and hanged properly so that equal force can be act easily on each of the joint. All the joints must be frictionless because when there is force act on them so that these joints applies flexibility and also able to maintain the same position as the bridge has to.  There are three types of truss and that includes Howe truss, Pratt truss, and warren truss.

For the lab report the students will work on the Pratt truss in which the structure will be in very suitable form and comparatively fewer materials are used. Also discussed some of the application that includes, through this many of the bridges are designed, used to make railways station platforms, also through the use of truss able to make the roofs for different factories, truss applications also applies to make the garage sheds for different parking places, because of its stiffness and flexibility this can easily been used to make the transmission towers and also some of the important applications in making the sport stadium designs and also for making the cranes. There are two types of connections are used for the truss that includes the Pinned Connection and the next one is the Gusset plate connection.

As in the increase of demands of the bridges because of the huge traffic jams in most develop countries so that the bridges are necessary.  But have seen that these bridges also effects the country’s economy so because of this the trusses structures bridges plays a very important role because of its design the amount of material that is used to make bridges decreases and also truss design structures are very powerful and rigid because it uses the triangular shape designs. These structures are one of the most important structures in our daily life because these structures can be installed very easily and they are also they are very strong structures

Overall we concluded that these truss designs meets easily to the requirements of different clients and also it provides a lot of scope for different departments. These designs are so much simple and also these can be installed very easily. In this report there is also deep discussion on the two methods that is used for the calculations of the trusses and then able to know which method is easy and which method is comparatively difficult and then concluded that the method of joint is one of the most smile methods to calculate the trusses.

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