Daniella Giannotti
ENGR 110 Engineering Graphics and Design
Ethics Case Study
1. Situation Summary
Article 1 was discussing a tragic building collapse because it got hit by an earthquake. There was an earthquake that struck near Christchurch, New Zealand that registered an aftershock of 6.3 in magnitude. The aftershock affected more buildings than the earthquake that his near the city five months prior. Because it caused more damages to buildings, there were more deaths. The majority of the deaths from the aftershock wave was from the collapse of one building.
The building was the CTV building which was built six stories high. It acted as an office building for the Canterbury Television station and held other tenants including a language school. The collapse of this building resulted in 115 deaths, which is 60% of the overall death toll. The building twisted and the concrete columns on the fifth floor blew out. Because of this the entire building came crashing down within 20 seconds of the earthquake.
The collapse of the building was investigated and it was found that the building's design engineer and the principal of the firm that employed him were incompetent to erect the structure. The design engineer was inexperienced with constructing a building taller than two stories. He had no previous background on how to make the building design the client wanted. The engineer was inexperienced with the software to run tests on his structure. When he ran an analysis on the structure he neglected to take into account the shape of the building. He did not find the center of rotation needed to calculate deflections at the corners of the building. Because he did not account for this information he underestimated how much the floor would move during an earthquake. There were many flaws with the structure that did not reinforce the building from seismic forces such as inadequate connections between the floor slab diaphragms and the building's north wall complex. The principal of the engineering firm was investigated and it was found that he knew of the incompetence of the design engineer.
2. Ethical Analysis Summary
Fundamental canon 1 of the ASCE Code of Ethics requires engineers to "hold paramount the safety, health and welfare of the public…in the performance of their professional duties." Tara Hoke says that this canon was violated because the engineer lacked the capability to “apply their expert judgment”.
Fundamental canon 2 states that: "Engineers shall perform services only in areas of their competence." In addition, she talks about Guideline a which states that engineers shall accept engineering assignments "only when qualified by education or experience." Guideline c establishes that engineers may not sign or seal "any engineering plan or document dealing with subject matter in which they lack competence." The design engineer clearly took on an assignment he was not qualified to work on therefore he violated canon 2. The principal of the engineering firm violated Guideline c of canon two by signing off on the design without properly peer reviewing it when he knew the engineer lacked the competency to take on the job.
3. Process to Find Article 2
When reading Article 1 I was thinking about how structures are built to withstand earthquakes and was interested in how the technology to protect buildings from the shocks of earthquakes has advanced in recent years. I wanted to understand the protections the engineers should have had in place to prevent the collapse of the CTV building from occurring. For this reason I found myself asking, what advancements have been made in how buildings are raised or analyzed in earthquake zones?
When researching for Article 2 to answer my question, I only used proquest as the database I searched on. I used the proquest database in high school so I was familiar with the layout of the database. The first terms I used were engineering and earthquakes. I found that these research terms were too broad because they gave me too many results that were not related to my research question. I decided to then search structural advancements and earthquakes. This search gave me 136 results and I found an article titled Earthquakes and Earthquake-Resistant Structures. In the related items column, I saw the article titled High-performance fiber-reinforced cement composites: An alternative for seismic design of structures. This sounded like an answer to my question and became my Article 2.
Abstract: An overview of recent applications of tensile strain-hardening, high-performance fiber-reinforced cement composites (HPFRCCs) in earthquake-resistant structures is presented. Applications discussed include members with shear-dominated response such as beam-column connections, low-rise walls, and coupling beams, as well as flexural members subjected to large displacement reversals. The results presented in this paper show that HPFRCC materials are effective in increasing shear strength, displacement capacity, and damage tolerance in members subjected to large inelastic deformations. The use of HPFRCCs in beam-column connections allowed total elimination of joint transverse reinforcement while leading to outstanding damage tolerance. Similarly, HPFRCC low-rise walls exhibited drift capacities larger than 2.0% with only minor damage at drifts ranging between 1.0 to 1.5%. One of the most encouraging results was observed in HPFRCC flexural members unreinforced in shear, which sustained reversed cyclic shear stresses as high as 2.7 MPa up to 6.0% plastic hinge rotation.
My article focused on the part of my question related to an advancement to how buildings are raised in earthquake zones. There is a new type of concrete composite called high-performance fiber-reinforced cement composites (HPFRCC). It is a flexible material that can self-strengthen before it fractures. This cement composite will outlast concrete and has the ability to deform before fracturing because when the fibers slip past each other they are strengthening the material.
Throughout the article they are analyzing test results to see how the material performs in earthquake-resistant structures. HPFRCC members with shear-dominated response were found to have exceptional shear distortion and damage tolerance capacity. “The test results found that beam plastic hinge regions with no transverse reinforcement under reversed cyclic shear stresses as high as 0.4√f'c (MPa) have exhibited rotation capacities of up to 6.0% with no significant shear strength decay. This indicates that there is a possibility of the elimination of transverse reinforcement requirements if HPFRCC materials are used.”
HPFRCC is costly to add into the “cementitious matrix” therefore it is only really used in regions where there is risk for severe earthquakes. This is because these areas have a higher demand for a material that has flexible qualities and has “substantial reinforcement detailing” to ensure satisfactory behavior during an earthquake. HPFRCC materials have high quality tensile behavior making them an appealing material in regions of flexural members subjected to large inelastic deformations combined with high shear, such as column and structural wall bases, and selected beam plastic hinge regions in frame structures. Article 2 ended by saying that design guidelines should be created to ensure the safety of the material on large scale structures.
4. Works cited
Hoke, T. (2018). Practicing Outside of Competence Leads to Tragic Consequences |
ASCE. Retrieved from https://www.asce.org/question-of-ethics-articles/mar-2018/
Parra-Montesinos, G. (2005). High-performance fiber-reinforced cement composites:
An alternative for seismic design of structures. ACI Structural Journal, 102(5), 668-675. Retrieved from http://rwulib.idm.oclc.org/login?url=https://search.proquest.com/docview/198362639?accountid=25133