By Dr. Mustafa Mashal and Dr. Bruce Savage
When it comes to a traditional civil engineering curriculum, precast concrete commonly is the last lecture in a reinforced concrete class. Graduating civil engineering students typically have minimal exposure to precast concrete design, production and construction during their programs. This creates a significant lack of knowledge among entry-level civil engineers who join the workforce.
If asked to design a prestressed girder or a precast pipe, most civil engineers have to learn the design procedures themselves. Idaho State University (ISU) wants this trend to change and is leading the way.
In 2019, the the National Precast Concrete Association (NPCA) Foundation and Precast/Prestressed Concrete Institute (PCI) Foundation joined forces to sponsor a unique curriculum for four years at ISU called “Precast Concrete Design Studio,” designed to change the status quo in precast concrete curriculum.
The Precast Concrete Engineering Studio (CE 4499/5599) at ISU is the only joint PCI/NPCA Foundations studio in the United States. The Studio is focused on transportation precast concrete products such as precast bridges, culverts and pipes. The studio is taught at senior undergraduate and graduate levels as a technical elective for three credits. Additional requirements with respect to homework, exam problems and lab work are required of graduate students. The content of the Studio is not fixed and can change every time the Studio is offered. This provides the opportunity for a student to take more than one Studio. Additionally, this helps to revisit the content of the class every year as the technologies evolve in the precast industry.
The Studio was taught for the first time at ISU in the fall of 2019. There were 25 students who took the class, including four graduate students. The class covered both precast bridges and culverts. However, more emphasis was put on the precast bridges.
The Studio was offered again in the fall of 2020. There were nine student this time, including six graduate students.
Student feedback from the initial class was incorporated into how we approached the second version. The class covered both precast bridges and culverts. However, more emphasis was put on the precast culverts and pipes.
Because of COVID-19, class lectures were conducted in a HyFlex manner as per ISU’s guidelines. This was a hybrid model where students can be present in the room or choose to attend synchronously online via WebRTC. Students were encouraged to attend the hands-on labs in person if they were healthy. All class lectures and lab work were recorded and made available to students on the course website. Travel outside of campus was restricted because of the pandemic, so the students could not travel to a nearby precast plant. The class provided a virtual tour of a precast plant for both PCI and NPCA products. In addition, most of the students in the Studio were able to see samples of full-scale PCI and NPCA products in the Civil Engineering Large-Scale Laboratory (CELL), which is an outdoor facility at ISU that has been used for a different project. The CELL has a variety of precast products that can be used as demonstration pieces.
Industry members from across the United States support and actively participate in the Studio. These professionals represent private and public entities, including the Idaho Transportation Department. Some of the students who took the Studio ended up working for the these individuals upon graduation.
A shorter version of the Studio with a focus on hydraulics for culverts to practicing engineers from the Idaho Transportation Department (ITD) also was conducted in 2020. The four-day course, led by Dr. Bruce Savage, consisted of 14 practicing engineering from two different ITD districts.
The content of the Studio is different than a traditional civil engineering class. It includes topics and opportunities such as structural and hydraulic design, hands-on work in the laboratories, large-scale structural testing, traveling to precast concrete yards and production facilities, listening to presentations from professionals in the industry and participation in precast concrete competitions at the national level. These activities are described in the following sections.
Class lectures consist of 35-40% of the course activities. Lectures are conducted in a traditional classroom setup. The class does have prerequisites such as Fluid Mechanics and Reinforced Concrete Design. Lectures cover introduction to precast concrete and materials, flexural and shear design of precast/prestressed girders, slabs, hydraulic design of culverts/bridges and design of concrete pipes. Students are assigned homework problems from the lectures. Graduate students are assigned more and complicated problems compared to undergraduates.
Tour of Precast Yards and Precast Structures
In-person and virtual visits are an important activity of the Studio where students get to observe and learn about how precast elements and structures are built. Students get to tour one to two actual precast concrete yards. It is preferred to arrange the tours on days where an actual project is being cast at the precast yard. Also, the plants are selected to include precast plants that produce PCI and NPCA products (e.g. above the ground and under the ground precast components). Students are required to write a summary report from these tours. The tours are supplemented with a visit to an actual precast concrete structure.
The Studio hosted many guest speakers from the precast and bridge industry from across the United States in the first Studio in 2019. For the second Studio in 2020, this was held long-distance due to travel restrictions imposed by the global pandemic. The speakers presented practical lectures on a variety of topics including the precast concrete for construction of resilient structures; wildlife crossings; durability and water-proofing; design and fabrication of underground precast products; precast segmental bridge construction; cement production and types; bridge bearings; small classroom activities; and formlining techniques.
The Studio typically includes five to seven laboratory sessions. These sessions are focused on students doing hands-on work to mix concrete, build their own concrete samples, and subsequently testing them (Figure 4). Laboratory tests included concrete slump testing, compressive strength, tensile testing, modulus of rupture, freeze/thaw test for durability, three-edge bearing testing of a full-scale reinforced concrete pipe and flume testing of hydraulics of culverts using the state-of-the-art laboratories at ISU. Students are required to write a detailed report from the laboratory work.
Student Membership and National Competitions
On the first day of the Studio, all students sign up for the PCI and NPCA Student memberships. PCI and NPCA offer significant technical resources in precast concrete as well as potential scholarships for students. Students are encouraged to participate in the national competitions organized by the PCI and NPCA. For instance, two teams of students from the Studio signed up for the PCI and NPCA Competitions in 2019. A team of six students participated in the 2019/2020 PCI Big Beam competition which came 2nd in the nation. Another team of four students was selected as a finalist in the 2020 NPCA Competition and came third in the nation. One other student from the Studio participated as an alternate candidate in the 2020 Project Precast organized by the PCI Foundation. Funding was provided by the NPCA and PCI Foundation for the faculty and several students in the Studio to attend professional conferences such as the PCI Convention, NPCA Convention, Precast Show, and PCI Committee Days and National Bridge Conference. Several students from the Studio applied for scholarship opportunities through NPCA.
Given the fact that the Studio is not a traditional class, detailed student surveys were collected to: 1) evaluate students experience of taking the Studio, 2) to refine the Studio based on the student’s feedback. Studio evaluations showed overwhelmingly positive feedback from the students. Some of the feedback for the question “what did you like best about this course?” are included verbatim below.
- Student 1. “I like the fact that it was more practical than book based.”
- Student 2. “Lab experiments.”
- Student 3. “Spent a lot of time doing design work. The lab work helped to understand some of the limitations of design and how to apply the design to the real world.”
- Student 4. “Exposure to real life application of theories and calculations learnt in class”.
- Student 5. “The course was more on practical level. With all the lab works and industry visit I actually got to learn much more than along with the lectures and guest speaker”.
- Student 6. “I really like going out to the plants and being able to see real problems. I also liked talking to industry leaders and their stories. This course helped me a lot in understanding not just precast concrete but the industry in general. Now I have a better understanding of what to expect once I graduate.”
The traditional civil engineering curriculum is strengthened by the inclusion of novel and practical courses such as the Studio where academics partners with industry. Such courses help students in many ways such as hands-on work and getting exposed to real-life projects and construction technologies. The Studio at ISU is an example of the successful implementation of new curriculum in precast concrete. Students overwhelmingly enjoyed the class and some were even inspired to join the precast industry upon graduation. The faculty at ISU are planning to make the Studio a permanent class in the civil engineering curriculum.
The authors are grateful for financial and other support from the PCI and NPCA Foundations. In addition, the Studio greatly appreciates the help from the Industry Champions in the United States. The assistance provided by the College of Science and Engineering as well as the Department of Civil and Environmental Engineering at Idaho State University with the curriculum is acknowledged. Furthermore, the authors are thankful for the opportunity from CPI Worldwide to publish their perspective on a Studio type curriculum in precast concrete education.
About the authors
Dr. Mustafa Mashal is an associate professor in the Department of Civil and Environmental Engineering at Idaho State University in the United States. He obtained his PhD, Masters, and Bachelors in Civil Engineering with a focus on Structural and Earthquake Engineering from the University of Canterbury in New Zealand, University at Buffalo-State University of New York in the United States, and Kabul University in Afghanistan, respectively. His research interests include precast concrete, earthquake engineering, low damage seismic design, and large-scale experimental testing. [email protected]
Dr. Bruce Savage is a professor and chair in the Department of Civil and Environmental Engineering at Idaho State University in the United States. He obtained his PhD, Masters, and Bachelors in Civil Engineering with a focus on Water Resources Engineering from Utah State University in the United States. His research interests include precast concrete, water resources, computational fluid dynamics, and large-scale experimental testing. [email protected]