February Post: Earthquake Time History Analysis

For my EQ answer #2, through performing different types of seismic analyses on buildings can contribute best designing a building for earthquake resistance, I had to research many different types of seismic analyses. I came across a seismic analysis called Time History Analysis. The importance of time history analysis is it can give a prediction on the performance level of a building during an earthquake. Time History analysis does this by measuring the accelerations at rock level and by studying the data of a structure in small periods of time in the structure's acceleration, force, and displacement. The video below, from MasterSeries: C&SCS Ltd, shows how to perform Time History Analysis is using a software program called Midas to test buildings with past earthquakes.

Blog 16: Advisory Meeting #2

EQ: How can a structural engineer best design a building for earthquake resistance?

Answer #2 (Write in a complete sentence like a thesis statement)*

Through using different types of seismic analyses on buildings can contribute in designing a building for earthquake resistance.

3 details to support the answer (a detail is a fact and an example)

Equivalent Static Analysis: An analysis that estimates base shear loads for each story of a low to medium rise building. Ex: Earthquakes put extra force into the building and buildings already have their own forces/ loads. Equivalent Static Analysis helps reduce some of the buildings own loads.

Time History Analysis: Visualizes or predicts performance level of a building under a given earthquake by measuring the history of specific areas that are more prone to earthquakes. Ex: Japan has a long history of earthquakes from low to high magnitudes. In engineering software, engineers can simulate the same magnitude of a Japanese earthquake in the 20th century and test their buildings.

Ground Motion Maps: Under building code ASCE7, these maps are used to measure seismic ground motion values. These values represent the spectral response accelerations in different periods of earthquakes. Ex: These maps are color coded and have a legend showing the distance between buildings and the color coded areas show the impact of the earthquakes.

The research source (s) to support your details and answer

 Source ID #: 11, Bagheri, Bahador "Comparatice damage assessment of Irregular Building Based on Static and Dynamic Analysis." International Journal of Civil and Structural Engineering. 3.3 (2013): 505-511. Print. (for Equivalent Static Analysis)
Source ID #: 33, Jumaat, Zamin. "Earthquake time history for Dhaka, Bangladesh as competent seismic record." International Journal of the Physical Sciences, 2011. Web. 26 Feb. 2014. (for Equivalent Static Analysis and Time History Analysis)
Source ID #: 30, Dowty, Susan. "Seismic Design Provisions of ASCE 7-10: Changes from ASCE 7-05." Structural Engineer, July 2011. Web. 20 Feb. 2014. (for Ground Motion Maps).

Concluding Sentence

Seismic analyses are important in designing buildings for earthquake resistance because they can measure the area and performance levels of buildings.

Blog 15: Independent Component 2 Approval

1.  Describe in detail what you plan to do for your 30 hours.

Similar to Independent Component 1, I plan to do extra mentorship for my Independent Component 2. During my mentorship, I will draft more building designs that are assigned by my mentor. This time the drawings that I will draft will be dealing with more earthquake resistant structures and will be different than the previous drawings that I've posted.

2.  Discuss how or what you will do to meet the expectation of showing 30 hours of evidence.

Like Independent Component 1, I will take pictures of my AutoCAD drawings to show proof of my 30 hours. Each drawing takes a few hours to complete, and my mentor also has to check if my drawings are accurate.

3.  And explain how what you will be doing will help you explore your topic in more depth.

Like I said the drawings that I draft this time will be more related to earthquake resistant structures, so I will be getting a better visual insight on earthquake resistant structures. Drafting on AutoCAD also helps me find my answers to my EQ because I'm drafting earthquake resistant structures, which are answers to my EQ.

4.  Post a log on the right hand side of your blog near your other logs and call it the independent component 2 log.

Ok I will do it.

Blog 14: Independent Component 1

Literal
(a) "I, Wesley Wu, affirm that I completed my independent component which represents 30 hours of work."
(b) I used primarily two books to learn basic concepts of structural engineering:

• Ching, Frank, and Cassandra Adams. Building Construction Illustrated. New York: Van Nostrand Reinhold, 1991. Print.
• Schueller, Wolfgang. The Vertical Building Structure. New York: Van Nostrand Reinhold, 1990. Print.

My mentor also helped me teach me the concepts of some building structures.

(c) On my blog

(d) Most of my work was focused on working on structures, assigned by my mentor, on a software program called AutoCAD. The structures I designed were mostly related with earthquake resistance since my EQ is based on earthquakes.

Interpretive

Like I've said, most my work is based on designing on AutoCAD. The pictures with red writing are my mentor's structure. Basically when my mentor is drawing this structures, he's explaning each structure in detail to me and how these structures have an important role to a building. After he explains the structureas to me, I go on the computer and draw these structures on AutoCAD. Once I've think I've completed the design, I show my designs to my mentor to check my work. If he approves my design, then he will teach me something else which is usually another building structure or just showing how structural engineers calculate the measurements that deal with width or length for building structures. If he disapproves the design I have to keep working on the design until my mentor approves it. Usually at minimum it will take me 2-3 hours to finish one design on AutoCAD. Regularly, I spend 4-5 hours in trying to finish one design.

Applied

During my Lesson 2 Presentation, I used these structures (the pictures posted on this blog post) as details for part of my answer 1. For example, my answer 1, by creating a better foundation using Special Moment Restraint Frames (SMRF) with isolators, these pictures are parts of the SMRF. These pictures help represent why the SMRF works during earthquakes. The picture with the panel zone helps give the SMRF structure more ductility features because there's a plastic hinge in the intersection of the column and the beam. The Grade Beam detail give a more detailed approach of the contents beneath the grade slab, showing soil, bolts, and rebars supporting the grade slab. This independent component helped me show a more realistic approach by using realistic designs of my answer 1.

Blog 13: Lesson 2 Reflection

1. Positive Statement

What are you most proud of in your Lesson 2 Presentation and why?

I'm most proud of my powerpoint because on my lesson 1, the look of my powerpoint was very bland, so I try to put more colors and themes this time.

2. Questions to Consider
       a.     What assessment would you give yourself on your Lesson 2 Presentation (self-assessment)?

       AE       P          AP       CR       NC

I would give myself a P

       b.     Explain why you deserve that grade using evidence from the Lesson 2 component contract.

I did what was required, which was turning in a poster with my EQ, coming in on time, presenting in the right length of time, turning in my final lesson plan, having an activity (LEGO tower activity), presenting an answer to my EQ (By creating a better foundation, using Special Moment Restraint Frames (SMRF) with isolators.), addressing the EQ (How can a structural engineer best a building for earthquake resistance), having materials, citing my research (my sources, mentor MCEER website) and cleaning up.

3. What worked for you in your Lesson 2?

Everyone participated in my activity and I also got good feedback about my activity.

4.  (What didn't work) If you had a time machine, what would you have done differently to improve your Lesson 2?

I would try not to face the audience with my back as much, so I would try to point to my pictures using a stick or something. I would also try to change my hook activity since the audience was giving me the same answers to my questions. 

5. Finding Value
What do you think your answer #2 is going to be?  

My answer #2: Designing structures with more ductility features.