<commit_before>---
layout: post
title: "Machine Design Project: Straw Truss Bridge"
description: "ME 174- Machine Design Project"
modified: 2016-03-19
tags: [Mechanical Engineering, project]
categories: [Mechanical Engineering]
image:
  background: triangular.png
  feature: /ME174/truss_cover.jpg
---
<style>
hr{
	border: 0;
    height: 1px;
    background-image: linear-gradient(to right, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.75), rgba(0, 0, 0, 0));
}
</style>
######2014-06-14
### Objectives
Design and construct a truss bridge within consraints outlined in **Specifications**.  Requirements for the project:

1. Agreement between predicted & measured failure loads for constructed bridge
2. Measured structural efficiency of the constructed bridge

<!-- more -->

### Specifications
Bridge will be constructed using a total of 25 plastic drinking straws.  Specifications and constraints will be as follows:

1. **Design:**
   * 12 inch span and 2 inch max width
   * Loading apparatus will provide 1 inch wide abutments on eithe rside of span for bridge to rest upon
   * Must be self-standing and function without attachment to loading apparatus
   * Must accomodate loading at mid-span. Weights will be loaded using 3/16 inch x 2.5 inch, transversely-oriented rod.  Wires attached to rod ends will connect to hanging weight beneath bridge.
   * No portion of the bridge may extend beneath plane defined by upper abutment surfaces.
   * Bridges must be trusses, not simple beams based on bundled straws
   * Straws can be cut to desired length, but may not be slit open to form webbing or gusseting
2. **Construction:**
   * Use of any other materieals is not permitted; nor are pins, tape, gussets, or other means of joining/support
   * Strongly encouraged to reinforce area around mid-span loading point to ensure that local deformation does not compromise bridge load-bearing performance unduly
<hr>
**Group Members:**David&nbsp;Chon, Andrew&nbsp;Chow, Clayton&nbsp;Chow, Jeffrey&nbsp;Chung, Alexander&nbsp;Decker

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The first plan was to come to a consensus on which type of bridge to create.  Most of the members had a good understanding of the different types of truss bridges: *Warren, Pratt, Howe and K* Truss bridge.  After further research online, the group came to an agreement on building the Warren bridge with a slight modification; by adding a support beam in the dead center.

**Estimated Loads**
<img src="/images/ME174/estimated_load.jpg">

| Header1 | Header2 | Header3 |
|:--------|:-------:|--------:|
| cell1   | cell2   | cell3   |
| cell4   | cell5   | cell6   |
|----
| cell1   | cell2   | cell3   |
| cell4   | cell5   | cell6   |
|=====
| Foot1   | Foot2   | Foot3
{: rules="groups"}

<TABLE BORDER=2 RULES=GROUPS> <THEAD> <TR> <TH>Name</TH> <TH>Food</TH> <TH>Price</TH> </TR> </THEAD> <TBODY> <TR> <TD>Starflower</TD> <TD>stir fied tofu</TD> <TD>5.95</TD> </TR> <TR> <TD>Miko</TD> <TD>vegetable rice soup</TD> <TD>4.95</TD> </TR> <TR> <TD>Andy</TD> <TD>hummus</TD> <TD>3.95</TD> </TR> <TR> <TD>Ping</TD> <TD>french toast</TD> <TD>5.95</TD> </TR> </TBODY> <TFOOT> <TR> <TH COLSPAN=2>Total</TH> <TD>20.80</TD> </TR> </TFOOT> </TABLE>

These assumptions/rough calculations were conducted 
&radic;<commit_msg>More testing tables<commit_after>---
layout: post
title: "Machine Design Project: Straw Truss Bridge"
description: "ME 174- Machine Design Project"
modified: 2016-03-19
tags: [Mechanical Engineering, project]
categories: [Mechanical Engineering]
image:
  background: triangular.png
  feature: /ME174/truss_cover.jpg
---
<style>
hr{
	border: 0;
    height: 1px;
    background-image: linear-gradient(to right, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.75), rgba(0, 0, 0, 0));
}
</style>
######2014-06-14
### Objectives
Design and construct a truss bridge within consraints outlined in **Specifications**.  Requirements for the project:

1. Agreement between predicted & measured failure loads for constructed bridge
2. Measured structural efficiency of the constructed bridge

<!-- more -->

### Specifications
Bridge will be constructed using a total of 25 plastic drinking straws.  Specifications and constraints will be as follows:

1. **Design:**
   * 12 inch span and 2 inch max width
   * Loading apparatus will provide 1 inch wide abutments on eithe rside of span for bridge to rest upon
   * Must be self-standing and function without attachment to loading apparatus
   * Must accomodate loading at mid-span. Weights will be loaded using 3/16 inch x 2.5 inch, transversely-oriented rod.  Wires attached to rod ends will connect to hanging weight beneath bridge.
   * No portion of the bridge may extend beneath plane defined by upper abutment surfaces.
   * Bridges must be trusses, not simple beams based on bundled straws
   * Straws can be cut to desired length, but may not be slit open to form webbing or gusseting
2. **Construction:**
   * Use of any other materieals is not permitted; nor are pins, tape, gussets, or other means of joining/support
   * Strongly encouraged to reinforce area around mid-span loading point to ensure that local deformation does not compromise bridge load-bearing performance unduly
<hr>
**Group Members:**David&nbsp;Chon, Andrew&nbsp;Chow, Clayton&nbsp;Chow, Jeffrey&nbsp;Chung, Alexander&nbsp;Decker

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The first plan was to come to a consensus on which type of bridge to create.  Most of the members had a good understanding of the different types of truss bridges: *Warren, Pratt, Howe and K* Truss bridge.  After further research online, the group came to an agreement on building the Warren bridge with a slight modification; by adding a support beam in the dead center.

**Estimated Loads**
<img src="/images/ME174/estimated_load.jpg">

|===
| Header1 | Header2 | Header3 |
|:--------|:-------:|--------:|
| cell1   | cell2   | cell3   |
| cell4   | cell5   | cell6   |
|----
| cell1   | cell2   | cell3   |
| cell4   | cell5   | cell6   |
|=====
| Foot1   | Foot2   | Foot3
|===
{: rules="groups"}

These assumptions/rough calculations were conducted 
&radic;
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