This project sought to examine and analyze the concepts associated with structural strength and integrity through the construction of two small scale bridges. The first bridge was designed and tested through the application tension to determine the maximum load bearing capability while the structural integrity of the bridge remained intact. The results of the test on the first bridge were found to be, bridge weight – 189.2 grams, maximum load bearing weight – 25,251.48 grams, and load to weight ratio 133.5. Utilizing the results of this test, a new bridge was then constructed using the same design as the first, as well as a number of newly implemented structural improvements that aimed to enhance the strength and durability of the bridge design. Improvements to the second bridge were made primarily in the area of additional supports through the application of double sticks in certain critical areas. As a result of these improvements, the second bridge was able to bear a greater amount of weight while retaining its structural integrity, as the test results were found to be, bridge weight – 197.4 grams, maximum load bearing capability – 29,998.6 grams, load to weight ratio – 131.97. These results indicate that the addition of enhanced support in key areas was able to effectively enhance the load bearing capability of the bridge. In the end, the most compelling conclusion that can be taken away from this is that a simple design can be quite effective in ensuring high levels of durability and stability in load bearing structures. Specifically, complex and convoluted designs may not always provide the best option moving forward. Further, there is great value in testing a design in order to determine its real capabilities and then using the test results to enhance the design and the overall structural capabilities. It helps facilitate the learning curve and enhances design initiatives undertaken in the future.
The primary objective of this project was to construct a bridge using balsa wood that exhibited adequate strength and durability to meet the load weight requirements outlined in the project instructions. As such, this project consisted of two individual parts, the first involving the construction of a bridge that has been scaled down to a maximum of 24 inches in length and 18 inches in height. While constructing the bridge, various considerations were made in order to ensure the durability and strength of the structure with particular emphasis on adequately addressing applied tension, as well as the potential stress associated with load bearing, such as is the case with a live or dead load. Once the bridge was completed and tested for strength, the second part of this project required the thorough examination and scrutiny of the testing results in order to identify relevant and effective areas of improvement to enhance load weight bearing strength and stability. The various innovations and quality improvement ideas were then applied to a newly constructed bridge that mirrored the original bridge, with the exception of the various improvements that were included in this new construction. Once the improvements were successfully applied, the bridge was once again tested to determine the strength and stability with primary emphasis on load weight bearing capabilities. The results from this test were then compared to the results of the first test in order to determine whether the implemented improvements resulted in successfully increasing the load weight bearing capabilities of the bridge, or whether the improvements did little to enhance the bridge’s capabilities. The following paragraphs will detail the major results of this project, as well as noteworthy conclusions that highlight and emphasize the important findings that should be taken away from this work to enhance future knowledge and understanding in the field of civil engineering.
The completion of the various components of this study ultimately yielded some very interesting results. Beginning with the first bridge that was constructed, which represents the first step of this project, the finished weight of the bridge was determined to be 189.2 grams (0.417 lbs.). When this first bridge was subjected to testing, which required the application of varying amounts of tension, it was determined that the bridge was able to bear a maximum load of 25,251.48 grams (55.67 lbs.) while maintaining its structural integrity. These results indicate that the load to weight ratio for this first bridge was 133.5. Despite the fact that these results are relatively impressive, it was still necessary to examine the results in order to design and implement structural improvements so as to enhance the overall strength, durability, and structural integrity of the original bridge design.
Importantly, it was very intriguing how successful the first bridge was with regard to effectively bearing substantial load weight and tension, particularly when one considers the overall simplicity of the structural design. Thusly, moving forward to design the second bridge required the consideration of a myriad of factors, each of which had the potential to enhance or improve the structural integrity of the bridge. In the end, somewhat minor modifications were applied to the second bridge, primarily in the area of additional structural supports. In particular, the second bridge was outfitted with additional supports in the form of double sticks in certain areas where tension and load weight would be considered the greatest. A test of this second bridge revealed that the improved design did in fact improve the load bearing capabilities of the bridge structure as the bridge weight was determined to be 197.4 grams (0.435 lbs.), while the bridge’s maximum load bearing capability was found to be 29,998.6 grams (66.13 lbs.). This results in a final load to weight ratio of 131.97.
Ultimately, the process associated with this project, which included the design, construction, and testing of two small scale bridges, facilitated the drawing of a number of valuable conclusions, although two in particular appear to stand out above the others. The first conclusion involves the improvement and redesign efforts undertaken when building and testing the second bridge. Specifically, the second portion of this project required the extensive examination of the bridge structure presented in the first bridge in order to determine effective ways to enhance structural integrity and load bearing capabilities. Conclusions were ultimately made that additional support through the addition of double sticks in certain key areas of the bridge would be quite effective at achieving this goal. The results of the testing of the second bridge indicated that this was correct as evidenced by the higher maximum load weight capability and load to weight ratio indicated for bridge two. The second important conclusion of this project involves the test results for the first bridge. Specifically, the first bridge was designed using a rather simple design. This simple design was determined to perform very well as it proved to have a maximum load bearing capability of 25,251.48 grams and a load to weight ratio of 133.5. These impressive findings that have resulted from a simply designed bridge indicate that significant complexity is not necessarily required to develop a bridge that is structurally sound. Rather, as long as the bridge is provided ample support to facilitate load bearing requirements, simplicity can be highly effective in the design of such structures.