Conducting K-12 outreach programs on university or college campuses focused on science, technology, engineering, and mathematics (STEM) disciplines is an essential part of the multifaceted effort for preparing future generations of engineers and scientists. However, the lack of structured frameworks to design and deliver activities and programs that maximize potential impacts poses a challenge. This case study contributes to filling this gap by presenting a six-step adaptable pedagogical framework whose intent is to provide meaningful structure for on-campus STEM outreach activities that emphasize collaborative, hands-on learning experiences for pre-college students. Successful implementation of the framework is demonstrated through the design of a civil engineering workshop on sustainable and hazard-resistant earth masonry, and its evaluation through the analysis of the feedback of 85 participants from three summer workshops for high school students between 2017 and 2019.

States, counties, and municipalities rely on pavement performance models to forecast future pavement conditions in their jurisdictions. Accurate prediction is essential for budget planning and the identification of candidates for rehabilitation. This study compares the performance of three different approaches to predict pavement conditions: (1) a sigmoidal or S-shaped curve; (2) a grey system model (GM); and (3) Gaussian process regression (GPR). All three models are trained on the same dataset for two types of pavements, asphalt with and without overlay and composite (i.e., asphalt over concrete), with each having two types of maintenance activities frequently performed by the South Carolina Department of Transportation. The trained models are then applied to separate test datasets. The prediction results indicate that GPR is the best model in three out of four cases using mean absolute error as the performance metric; the exception is the case involving the prediction of pavement serviceability index for asphalt pavement with mill-and-replace 1–2 in. + overlay 400 pounds per square yard rehabilitation treatment. When using mean absolute percentage error and root mean squared error as the performance metrics, the GPR model is the better model for predicting conditions of composite pavements, while the [Formula: see text] model is the better model for predicting conditions of asphalt pavements.

The purpose of subdividing pavement sections is to create sections with similar characteristics that can be meaningfully handled as units in pavement management systems. Data collected for each unit can be used to assess pavement preservation, rehabilitation, or reconstruction needs; or utilized in the calibration of distress models using the mechanistic-empirical pavement design guide in PavementME. In this study, a procedure was developed to subdivide three newly constructed concrete pavement sections in South Carolina by examining the variation in compressive strength, f_c^' , measurements obtained from quality control cylinders cast each day from the pavement section construction pours. The variation in compressive strength along the length of a pavement section, by direction of traffic, and by lane, was investigated. Data were analyzed using the cumulative difference approach and statistical methods. The method is shown useful for delineating sections when changes to concrete mixtures are not well documented, and identifying locations that have a higher proportion of strengths not meeting design value.

State departments of transportation recognize the need to incorporate pavement structural condition in their pavement performance models and/or decision processes used to select candidate projects for preservation, rehabilitation, or reconstruction at the network level. However, pavement structural condition data are costly to obtain. To this end, this paper develops and evaluates the effectiveness of two machine learning methods, Random Forest (RF) and eXtreme Gradient Boosting (XGBoost), for predicting a flexible pavement's structural condition. The aim is to be able to predict whether a pavement section's structural condition is poor or not based on Annual Average Daily Traffic (AADT), truck percentage, and speed limit. The structural condition of a pavement is considered poor if the Surface Curvature Index (SCI12) is above 3.3. The models are developed using 950 miles of Traffic Speed Deflectometer (TSD) data collected along 8 primary routes in South Carolina. The performance of the machine learning models was compared with that of a logistic regression model. When the trained models are applied to the test data, the prediction results indicated that the XGBoost and RF models outperform the logistic regression model by 12% and 8%, respectively. XGBoost outperformed RF by 4%. With XGBoost found to be the best among the three models evaluated, its performance was examined using other poor structural condition threshold values; its prediction accuracy is found to be robust across the different scenarios. AADT and truck percentages are found to be significant factors whereas speed limit has no effect on a pavement's structural condition.

This paper presents a description of post-flood reconnaissance and geotechnical investigation of four earthen dams that were breached or damaged following an extreme flooding event in South Carolina in 2015. As a result of unprecedented rainfall and flooding that occurred during a five-day period at the beginning of October in 2015, a total of 51 earthen dams failed and nearly 200 were damaged. Many of these dams failed due to overtopping that led to a breach of the dam. Among the four dams investigated, full breach was observed at three dams; two of which were overtopped, and one was not. The fourth dam was not breached but was severely damaged. For each of these dams, the paper documents background information, pre-flood conditions, post-flood field observations and measurements, and laboratory testing results of collected soil samples. Impacts of vegetation on the dams and the effects of dam failure on critical infrastructure are also presented. The detailed descriptions and geotechnical investigations of the dam failures presented herein serve as case histories that can be used for dam breach modeling and risk assessment of dam failure.

Unpaved roads are subject to rapid deterioration and large deformations under mechanical and environmental stresses that can render them impassable. Prior work has shown that plastic soils can be mixed with a polymeric chemical admixture to create a hydrophobic material and potentially minimize these issues. The purpose of this work is to assess the durability of a low plasticity clay soil treated with a chemical admixture by evaluating changes in physical and mechanical behavior when subjected to alternating cycles of wetting and drying. Volumetric change, water content change, and mass loss were measured at the completion of each one of up to twelve wetting and drying cycles. Unconfined compression tests were performed after select cycles to assess changes in mechanical properties. Tests were also performed on specimens stabilized with Type I/II portland cement for comparison. It was found that the specimens with chemical admixture treatment survived a full twelve cycles of wetting and drying. The volume changes of the specimens were small (+/- 2 %) and there was no apparent reduction in strength. The chemically stabilized soil retained its physical and mechanical properties in a manner comparable to cement stabilization of the same soil. These results suggest that the CAT produces a sufficiently stable material when subjected to alternating wetting and drying conditions and has potential applications in improving long-term performance of unpaved roads.

For two consecutive years (fall 2014 and 2015), two weeks of the civil engineering materials laboratory course at the University of South Carolina were dedicated for a student-centered, problem-based learning (PBL) module about nanomaterials in cement composites. Implementation of this module was part of a larger curriculum enhancement and faculty development project to integrate student learning of nanotechnology using a PBL network of courses. The project goal was to elevate knowledge of and elicit critical thinking in the complex and increasingly important area of nanomaterial applications in civil and environmental engineering. Specifically, this module was designed to address the challenge with student understanding of the nanoscale. Students were presented with a current problem set in the context of nano-amended cement composites for below-ground nuclear waste storage at a local site, where leaching is of concern. The driving question, for which students were asked to estimate a solution, was “What is the amount, using wt% as units, of multiwalled carbon nanotubes needed to attain at least a 20% increase in compressive strength in Type I ordinary Portland cement mortar?” This question was presented in a decision worksheet that was completed as individuals and in teams before and after strengthening their understanding of fundamental concepts through active learning exercises. This paper reports on the salient results of this two-year experience. It discusses and demonstrates how student illustrations and written evidence from decision worksheets and active learning exercises were used for a qualitative assessment of: (a) recognition of relevant concrete properties (prior knowledge); (b) student learning of fundamental nanomaterial properties (new knowledge); (c) an understanding of the nanoscale in the given problem context; and (d) how students in teams influence each other’s learning processes in a collaborative PBL environment.

A series of devastating dam failures caused significant damage to communities throughout South Carolina in October 2015. The South Carolina Department of Health and Environmental Control (SC-DHEC) reported a total of 47 dams breached, with 22 of them located in the Columbia area. South Carolina has at least 2,500 dams, of which, 205 are classified as high-hazard potential structures. Many of these dams are privately owned and often lack the attention and funding needed for maintenance, monitoring, and upgrades. This paper presents results from a post-flood reconnaissance study aimed to collect perishable data from select dams that failed during the extreme flooding in Columbia. The study included collection of extensive photographic evidence and documentation of descriptive information related to the failure; collection of soil samples, and field and laboratory geotechnical tests. These data form valuable sets of well-documented case histories that can be used in the future to support large-scale research for advancing our fundamental understanding of complex failure mechanisms in extreme scenarios.

Influence of Chemical Stabilization on Flexural Fatigue Performance of Subgrade Soil Moeen Nazari, University of Oklahoma; Rouzbeh Ghabchi, South Dakota State University; Musharraf Zaman, University of Oklahoma; Sesh Commuri, University of Nevada, Reno The chemically-stabilized subgrade (CSS) soil layer in a pavement structure can undergo flexural fatigue as a result of a high number of loading cycles and brittleness of the stabilized soil. The type and amount of chemical stabilizing agents are generally selected based on the results of unconfined compressive strength (UCS) and/or resilient modulus (Mr) tests. The UCS and Mr tests help characterize the compressive behavior of the soil and do not specifically assess the flexural behavior of the CSS layer under cyclic loads. This study aims to evaluate the fatigue life of the CSS layer and compare it with other common indicators such as UCS and Mr. For this purpose, a series of UCS, Mr and four-point flexural fatigue (FPFF) tests were conducted on CSS soil samples. The materials tested in this study consisted of six blends of a lean clay stabilized using cement kiln dust (CKD) and hydrated lime. The CKD was mixed with the soil at 5, 10, and 15% by weight of dry soil. The hydrated lime was mixed with soil at 3, 6, and 9% by weight of dry soil. It was found that while increasing the amount of stabilizing agent resulted in higher UCS and Mr values, it had an adverse effect on the fatigue life of CSS. The specimens containing 5% CKD and 3% lime showed the highest fatigue lives compared with other mixes. It was concluded that the strain endured by the material at the peak load (strain at failure) plays an important role in the fatigue life of the CSS. CSS samples with a high strain level at failure possessed a high fatigue life while those with a lower strain at failure failed after a relatively low number of loading cycles.

South Carolina recently experienced a 1000-year rainfall event that caused catastrophic flooding and crippled the transportation infrastructure. Initially, almost 400 roadways were closed due to flooding, a majority of which were closed from roadway washouts. Many of these roadway washouts resulted from failure of the pipe culvert soil system beneath the roadway. The culvert infrastructure is critical to not only preventing flooding during normal and extreme conditions but is integral to proper road and highway maintenance. This paper presents the results from a post-flood reconnaissance study aimed to collect perishable data from sites where pipe culverts failed and roadways were washed out. The study included collection of extensive photographic evidence and documentation of descriptive information related to the failure; collection of soil samples; and field and laboratory geotechnical tests.

A two-step research program for undergraduate students was developed and implemented across the 2015 spring-summer terms in the Department of Civil & Environmental Engineering at _____. The first step requires students to complete a research course in the semester prior to the research experience. This course is different from an independent learning or special research topics course. It is taught in a traditional classroom setting but emphasizes interactive learning of the research process. Students are taught how to identify meaningful research topics and develop research questions based on the identification of gaps in knowledge in the relevant literature. The course culminates with the submission of a research proposal, which is the main deliverable and student assessment instrument for the course. Students are required to meet and work with their research mentor during the semester. The second step is to conduct the research as outlined in the proposal. This program was implemented as part of a NSF-supported project to create the Nanotechnology LINK (Learning Integration of New Knowledge) curriculum enhancements. This project exposes undergraduate students in our department to fundamental concepts and applications in nanotechnology, with an emphasis on end-of-life management of products containing nanomaterials. This content is delivered across multiple linked courses. To complement and extend student learning of nanotechnology within the curriculum, research-based learning opportunities were created for a select cohort of students. The first cohort of five students was assembled from a group of 22 internal applications. This paper will describe the application and selection process, which was conducted during the fall 2014, and the subsequent impacts of the research course (spring 2015) and summer research experience (summer 2015) on student understanding of the research process. Students are encouraged to culminate the research program through the pursuit of Graduation with Leadership Distinction (GLD) in Research. Four of the five students in the first cohort intend to earn the GLD in Research, which is a university-wide program available to all undergraduate students. Successful recipients must demonstrate (1) extensive, purposeful engagement beyond the classroom; (2) understanding of course concepts in “real world” settings; and (3) application of learning to make decisions and solve problems. Requirements include participation in enhancement activities (lectures, workshops, events); completion of approved courses relating to their experience; delivery of a public presentation; and production of an e-portfolio that demonstrates their learning. This paper will provide an example of one student’s completed requirements towards the distinction.

Four soils, three low plasticity clays and one high plasticity silt, were treated with a chemical admixture that creates a hydrophobic composite material when mixed with soil. Specimens were subjected to cycles of wetting and drying to assess durability. Volume change, water content, and mass loss were studied over the course of up to four wetting and drying cycles. Unconfined compression tests were performed to evaluate changes in modulus and strength following each wetting and drying cycle. From the results, there is some measurable volume expansion (<3% in all cases) and mass loss (<3.5%) when submerged in water even though the soil is treated to create a hydrophobic composite material. Increases in strength were observed after 1 and 2 cycles of wetting and drying for three of the treated soils. With additional cycling, the strength and moduli decreased. Compared to untreated specimens, specimens treated with the chemical admixture had greater volumetric stability, less soil mass loss, and for the three low plasticity clays, had a higher maximum stress and a larger modulus.

Archaeological sites continue to be discovered and explored around the world. The archaeological materials buried within these sites can be of great cultural significance, but the process of exploration and preservation is challenging in these fragile and complex environments, especially in high population areas with substantial development. Civil engineers are often engaged with archaeologists in one of two roles, either as first finders on construction sites or as active contributors in preservation efforts on existing archaeological sites. In both cases, the effect of the interactions between the two parties can be elevated through improved understanding of archaeological needs, with the goal of establishing more routine and productive collaborations. A review of the professional intersections between the civil engineering profession and the archaeological community is presented in this paper. In the last few decades, there have been increased legislative efforts to protect archaeological sites, and a historical review of the effects of legislation for site conservation in the United States and United Kingdom is presented. On the basis of a cross-disciplinary literature review, the dissemination of cooperative relationships between civil engineers and archaeologists appears to be increasing, which is also indicated by the growth of strategic conferences and workshops. Lastly, this paper discusses prominent contributions that civil engineers have made, and should continue to make, in three specific areas of archaeological practice: subsurface exploration, foundation reuse and mixed foundation design, and site reburial.

Development of an Integrated Curriculum for Educating Engineers about Nanotechnology: End-of-Life Management of Nanomaterial-Containing WastesThe rapid development of the nanotechnology field and its prevalence in our daily livesnecessitates undergraduate engineering students be prepared to enter a workforce wherereferences to and use of nanotechnology will likely be commonplace. Students not only need tobe well-versed in the fundamental aspects of nanotechnology, but also need to understand theimpact and implications of nanotechnology in their respective fields. For civil and environmentalengineering (CEE) students, this often involves areas such as nanomaterial-incorporation withinconstruction materials or nanomaterial-enhanced environmental remediation. However, it is alsoimportant that CEE students understand the environmental implications of nanomaterial use andsubsequent end-of-life management. As nanomaterial incorporation within consumer products,construction materials, and other medical or electronic devices increases, so will the need foreducated engineers to develop environmentally sound end-of-life management strategies forthese nanomaterial-laden items.This paper describes the development and implementation of an integrated undergraduatenanotechnology theme within the current civil and environmental engineering curriculum at_______________. This integrated approach is referred to as a Nanotechnology LINK, orLearning Integration of New Knowledge. The curriculum theme focuses on the environmentalimplications associated with the end-of-life management of nanomaterial-containing products,materials, and nanomaterial manufacturing waste streams. A major component of this integratedcurriculum is the development of a network of nanotechnology problem-based hands-on learningmodules using a pedagogical approach referred to as Environments for Fostering EffectiveCritical Thinking (EFFECTs). EFFECTs use student-centered learning strategies to promotedeep learning, enhance conceptual understanding, and stimulate growth in critical thinking skills.These exercises are being used throughout our curriculum, in sophomore, junior, and senior levelcourses. The EFFECTs are geared towards introducing students to important aspects ofnanotechnology fundamentals (e.g., surface area, surface chemistry), as well as potential issuesassociated with nanomaterial disposal (e.g., transport in waste environments, health concerns).As part of this integrated approach, students assemble nanotechnology-themed electronicportfolios, building content knowledge as they advance through a sequence of courses. The mostsignificant feature of this e-portfolio is a progression of student-generated nanotechnologyconcept maps that represent the accumulation of student knowledge at discrete points in thesequence.

This paper describes the Environments for Fostering Effective Critical Thinking (EFFECTs) pedagogical framework that has been developed and implemented across the civil and environmental engineering curriculum at the University of South Carolina. Thirteen unique EFFECTs have been created to date, impacting seven different courses. This instructional approach has been used in courses at all undergraduate levels, from first-year introduction courses to upper division elective courses. The cumulative application of EFFECTs facilitates the integration of technical and professional skills to meet programmatic student outcomes. This paper provides a map of the ABET and ASCE student outcomes that are addressed with EFFECTs, with appropriate examples from different EFFECTs modules. In terms of professional student outcomes, the EFFECTs framework is designed to enhance student communication skills, teamwork, and knowledge of contemporary issues. In addition to these three core outcomes, each EFFECT can incorporate other professional skills, depending on the nature and content of that particular EFFECT. The implementation of EFFECTs has reached a point where most, but not all, upper division students (seniors) have been exposed to the EFFECT approach at least once during their academic program. Survey results on student self-perceptions of professional skill development are reported in this paper. Based on those findings, teamwork is the highest rated outcome. Professional skill development was also found to improve significantly when students are exposed to EFFECTs in more than one course.

Physical soil models are often used to study slope failure in centrifuge and/or shaking table tests. An important part of such physical modeling is to monitor the subsurface deformation patterns of failing slopes. As an emerging technology to monitor internal deformation of geo-materials, time domain reflectometry (TDR) has been successfully applied in field monitoring of unstable slopes. This paper presents the development of a custom-made TDR sensor and its application in a 1-g slope failure model test. The test results show that the TDR system is capable of capturing localized shear deformation in small soil models. Trial studies of using the TDR system in centrifuge and shaking table experiments demonstrate that the system has the potential of being successfully applied in centrifuge and shaking table testing.