Role of Civil Engineering in Poverty Alleviation

Poverty can be history if everybody helps in even a small way to alleviate it. There are many ways of eradicating or reducing poverty. Civil engineers, in particular, can contribute in building a better future of our society through the three of their majors tasks: Design, Construct and Maintain. KHRPN (Kahirapan) is a video by Joenel Galupino of De La Salle University, Manila - an entry to the PICE-LNM Chapter's Discover Ciivl Engineering @ You Tube Photo-Video Competition. Watch it and post your comments.

Green Buildings and Structural Engineering

The main theme of the 33rd IABSE Symposium at Bangkok (Sept. 9-11, 2009) is "Sustainable Infrastructure." The International Association of Bridge and Structural Engineers (IABSE) recognizes the important role of structural engineers in ensuring sustainability in their creations to ensure that energy and natural resources are still available for the future generations.

The keynote lecture on "Green Buildings and Structural Engineering" by Gene Corley (USA) highlights how structural engineers can contribute to sustainability by following the LEED Green Building Rating System - a framework for asssessing building performance and meeting sustainability goals. A rating of 40 points will earn a building a LEED Certification. Structural engineers, in particular, can earn LEED points in the category of Materials and Resources and the following subcategories:

(a) Building reuse - instead of demolition, the building structure or shell is reused.

(b) Construction waste management - diverting construction and demolition waste from ladfill into other uses

(c) Materials reuse - a portion of the materials of the project must be salvaged or recycled

(d) Recycled content - use of materials with "recyled content"

(e) Regional materials - use of local materials will reduce transport and energy cost

Structural engineers should design building which are adaptable to provide for ease of alteration or amendment in use. Buildings which consists of elements that can easily be deconstructed are preferrable for possible reuse. By proper planning and efficient design and knowledgeable of sustainability concepts, green buildings can be successfully built.

The author (center) with Filipino engineers infront of the IABSE booth.

Online MS/PhD Programs in Asia

The general consensus the world over is that online degrees are not as acceptable as their regular counterparts, but that perception is slowly changing as the face of academia itself undergoes a significant change. Today, even doctoral programs are being offered online and are accepted in all kinds of job settings as equal to those degrees that have been earned in traditional classrooms.

The situation in Asia is not that different from the rest of the world. People turn to online degrees for various reasons, the most significant of them being time. When it comes to a graduate program like MS or a doctoral degree like PhD, most of us prefer to earn them online because it allows us to continue with our work and study during our free time. The schedules are flexible enough to allow us to multitask with efficiency. We don’t need to take time off work and we get our regular salary as well. Besides, some employers are willing to sponsor their employees’ education, so this means you gain knowledge and are in a position to climb up the career ladder, all at no extra cost.

Various universities across Asia offer online MS and PhD programs, and some of the more prominent ones are The Open University of Hong Kong (China), University Sains Malaysia(Malaysia), University of the Philippines (Philippines), and the Indira Gandhi National Open University (India). While most of them do not require on-campus residency, some do mandate the same for a short period, either a few months or 15 to 20 days.

When you choose to study online, consider the discipline and the university rather than just the degree itself. For example, even a master’s degree from a prestigious university may hold more value than a doctoral degree from an unaccredited one. Or, a degree in a field that offers various job opportunities is infinitely more useful than one that is difficult or more interesting. Also, check the accreditation of the college you’re applying to and verify its credentials before you enroll. It’s best to talk to alumni of the college and discuss their experience before you decide that this is the university for you.

This guest article was written by Adrienne Carlson, who regularly writes on the topic of engineering degrees online. Adrienne welcomes your comments and questions at her email address: adrienne.carlson1@gmail.com

Genetic Algorithms in Optimum Concrete Design

Engr. Alden Balili, my graduate thesis advisee did a research on the application of genetic algorithms (GA) in the optimum design of reinforced concrete (RC) space frames considering seismic provisions of the code. The process of GA and its application to the optimization of space frames is in the figure below. Initially, the sizes of the beams and columns of the space frame are randomly selected which becomes the initial population. These sizes are then used by a separate Finite Element Analysis program to determine the member forces which are required in the design of the members including the amount of steel reinforcements. A database of the beam and column sections is used in the design process. The provisions of the National Structural Code of the Philippines (2001) are incorporated in the fitness evaluation of the solution or individual to satisfy the strength and serviceability requirements. The GA procedures of selection, cross-over, mutation and leader reproduction are then applied to generate a new population of solutions. He conducted GA simulations to determine the behavior of the optimization procedure using the different GA procedures like binary vs gray coding, leader reproduction and mutation. Based on his simulations, a new type of leader reproduction called modified leader reproduction was proposed. It was found out that this feature improved the effectiveness and efficiency of the concrete optimization algorithm to acquire the optimal values.

A paper on this study will be presented at the IABSE 2009 Conference at Bangkok, Thailand on Sept. 9-11, 2009.

A Neural Network Model for Shear of RC Beams

Experiments have shown that as the depth of the beam increases, the intensity of shear stress decreases especially in lightly reinforced beams. This phenomenon is referred to as “size effect”. Shear strength is not constant as given by some design codes like the ACI. To understand size effect, an artificial neural network (ANN) model was developed for RC beams without stirrups which fail under diagonal tension.

The ANN model consists of five input nodes representing (1) the compressive strength of concrete, f’c, (2) beam width, b, (3) effective beam depth, d, (4) shear span to depth ratio, a/d, and (5) longitudinal steel ratio. The output is the shear stress, Vu/bd. The graphical user interface of the Visual Basic program of the ANN model is shown.

The figure shows the simulation where the depth (d) was varied from 20 cm to 100 cm for two values of f’c and a/d and constant values for b at 15 cm and r at 2.75%. The size effect is obvious where the shear stress decreases with increasing depth. The experimental results by Kani shows a similar trend as the model. The shear stress also depends on the shear span to depth ratio – a shorter beam (a/d = 2.5) has a larger shear strength than a longer beam (a/d = 5.0).

How safe our our large RC beams with respect to shear failure? Structural engineers must take note of the decrease in shear strength of concrete for large beams so that they can provide adequate shear reinforcements or stirrups.

Reference: Oreta, A.W.C. (2004). "Simulating size effect on shear strength of RC beams without stirrups using neural networks." Eng'g Structures 26(2004) 681-691, Elsevier.

Collapse of a Building in Shanghai

"A 13-story under construction apartment building in Shanghai's Lotus Riverside complex fell to its side on June 27, 2009. During construction, a 4.6-meter-deep underground garage was dug on the south side of the building while a mound of soil heaped up to 10 meters high was located on the other side. This caused a difference in pressure on two sites of the building, which resulted in the collapse of a building in Shanghai" according to the China Daily. The lateral pressure caused the piles to snapped resulting in the foundation failure and tilting of the building.

Learning Lessons: The 1990 Luzon Earthquake

On July 16, 1990, an earthquake with magnitude 7.8 struck central Luzon. The human consequences were severe - at least 1200 people were killed and more the 3000 injured. Major destruction occured in Baguio City where hotels and school buildings collapsed like pancakes and Dagupan city where extensive liquefaction caused settlement of buildings and bridges. What lessons can we learn from this earthquake? This video - part of the "Understanding Earthquakes and Disasters: Photo-Video Presentations" highlights some lessons from the 1990 Luzon Earthquake. This video can also be viewed (full screen) and downloaded at YouTube.

A Neural Network Model for Confined RC Column

Artificial Neural Networks (ANN) are information – processing systems whose architecture mimic the biological system of the brain. Recently, civil engineers have utilized ANN for various applications especially in the modeling of civil engineering systems.

In my case, I developed an ANN model for predicting the confined compressive strength and strain of a circular reinforced concrete column. The model has seven input nodes: (1) unconfined concrete cylinder strength, f’c; (2) concrete core diameter, d, where the core is the part of the section enclosed by the centroidal axis of the hoop or ties; (3) column height, H; (4) yield strength of lateral reinforcement, fyh; (5) volumetric ratio of lateral reinforcement; (6) tie spacing, s ; and (7) vertical steel or longitudinal reinforcement ratio. The two output nodes, on the other hand, represent the peak stress or compressive strength of confined concrete circular column, f’cc and the strain, ecc , at peak stress. Shown below is the GUI of the Visual Basic program of the ANN model.

The predictions of the compressive strength or peak stress, f’cc, of confined concrete columns and the corresponding strain, ecc, have been a subject of various researches, both analytical and experimental. The values of these two parameters are usually used in the analytical models developed for describing the stress-strain relationship for confined concrete.

You may run the ANN model at http://mysite.dlsu.edu.ph/faculty/oretaa. Go to the Software section. Papers on the model can also be downloaded from this site.

The World Without Engineers

What will the world might look like if there were no engineers like civil engineers, electronic engineers, mechanical engineers, etc. You may download from the website of Agilent Technologies' Educators Corner a poster or screensaver on "The World Without Engineers." Here is my favorite - The World Without Computer Engineers.

Indeed, the advancements and innovations in computers have changed our ways of computing and data prcessing. In my case, I experienced using some of the computing tools shown in the image above. I still remember when I was a kid, my father taught me how to use the abacus. During my high school days, we were taught how to use the slide rule in our chemistry class. Then the scientific calculator was born just before I graduated in high school. During my college years, we used computer cards in our computer programming classes using the FORTRAN language. Then I also used a programmable calculator using BASIC language. My first computer was an Apple Computer whose memory is in kB. Today, we have computers which are fast and with almost unlimited memory space in terabytes.

The Little DVD of Civilisation

Take a look at at the amazing ways civil engineers overcome the challenges of creating and maintaining our infrastructure for us, and for future generations. This video, "The Little DVD of Civilisation", which was created by the Institution of Civil Engineers promotes the importance of how civil engineers build the quality of life like supplying clean and safe drinking water in Ethiopia, reducing flooding in London, construction of man-made island for the new airport in Hong Kong, development of sustainable housing community and preserving historical structures like Leaning Tower of Pisa. Civil engineers play various specialized roles in creating a safe and sustainable built and natural environment. Watch this video because "when you understand civil engineering, you see the world differently."

Play BEAT THE QUAKE

What precautions should you do to protect people from harm and reduce damages to property in case an earthquake occurs? Test your knowledge on earthquake preparedness and safety by visiting http://www.dropcoverholdon.org/ and play "Beat the Quake." In this game, you are challenged to make your home a safe place during an earthquake. You click on each object shown in the room and you choose an option on how to secure it. But you must hurry, because the earthquake may happen any time. After the quake, you will see how the objects responded to your design. This is both fun and educational especially to kids. Are you ready to play "Beat the Quake"?

On Shaky Ground

On Shaky Ground (5:55 min). This is a presentation of various types of earthquake geotechnical hazards and their effects on structures. These hazards include ground ruptures, soil liquefaction and land slides. Since a geotechnical hazard can cause a serious effect on a community, reducing the impact of these hazards must be addressed. This video is part of the "Understanding Earthquakes and Disasters: Photo-Video Presentations for Public Awareness and Education."

Bridges are falling down!

Bridge superstructures and substructures have been damaged in recent earthquakes like the 1994 Northridge earthquake and 1995 Hyogeken-Nanbu earthquake in Japan. Bridges are Falling Down ( 5:52 min) is a photo-video presentation that shows the different types of damages in bridges and some retrofitting techniques. This video is part of the "Understanding Earthquakes and Disasters: Photo-Video Presentations for Public Awareness and Education."

Buildings: Shake, Rattle and Roll

In past earthquakes, many buildings have collapsed or were damaged due to ground shaking or foundation failures. The presentation shows the common types of failures of buildings like soft stories, short columns, torsion, poor detailing and ductility in reinforced concrete columns and beams, and irregular structures. The importance of seismic retrofitting and strengthening of existing structures is also highlighted.

This video is part of “Understanding Earthquakes and Disasters: Photo-Video Presentations for Public Awareness and Education, ” a project funded by the DLSU-Manila University Research Coordination Office (URCO).

Preparing for the BIG ONE

The key to reducing the impact of earthquake hazards is disaster preparedness and mitigation. Since the Philippines is an earthquake country, it is important to prepare against seismic hazards. This video poses some questions and tips to consider with regards to design and construction of structures, seismic assessment and retrofitting and community disaster preparedness. PHIVOLCS tips before, during and after an earthquake are also presented.

This video is part of the author's photo-video, "Understanding Earthquakes and Disasters: Photo-video presentations for public awareness and education", a project supported by the University Research Coordination Office (URCO) of DLSU - Manila.