Civil Engineering

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The Department of Civil Engineering has strong affiliation with the Western Transportation Institute (WTI) and the Center for Biofilm Engineering (CBE), a graduated NSF research center. The department is also affiliated with a Montana Department of Transportation Design Unit located on the MSU campus.

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Impact of deicing salts on pervious concrete pavement
(Frontiers Media SA, 2023-06) Feng, Lichao; Zhang, Yongran; Wang, Xiaowei; Mery, Stephene; Akin, Michelle; Li, Mengchao; Xie, Ning; Li, Zhenming; Shi, Xianming
Two pervious concrete projects (named as SR28 and SR431), with the same mixture design but different winter maintenance activities, were included in this research. Both projects are located in the Lake Tahoe area, Nevada, United States. Testing results indicated that the mechanical properties were significantly higher in SR28 cored samples than the ones in SR431. It was found that the SR28 pieces have fewer air voids, while the SR431 samples have higher water absorption and hydraulic conductivity, and the SR28 samples show fare better performance against repeated freezing and thawing cycles than the SR431 ones. scanning electron microscope pictures of crack surfaces in cores taken from SR28 indicate that the cement binder phase has been largely retained. However, in the coring sample of SR431, needle-shaped residues can be seen within the cement binder phase and an abundance of precipitated micro-sized crystalized particles can be observed. On a micrometer scale, the μCT examination reveals that the porosity of SR28 samples is significantly less than that of SR431. The analyzing results give a clue to demonstrate the durability of pervious concrete pavement can be attributed to the construction quality control, maintenance activity, or the weather and locations of the field sites.
Use of Finite Difference Numerical Technique to Evaluate Deep Patch Embankment Repair with Geosynthetics
(2015-03) Perkins, Steve W.; Cuelho, Eli V.; Akin, Michelle; Collins, Brian
Low-volume roads constructed in steep hillside terrain by cut and cast techniques may experience instability in the form of excessive subsidence that leads to large cracks and differential movement along the roadway bench. The technique of deep patch embankment repair with geosynthetics (DPERG) has been employed in the western United States; DPERG generally involves a 1- to 2-m-deep excavation that is backfilled with compacted granular soils and one or more layers of geosynthetic reinforcement. The design goal of a DPERG is not necessarily to eliminate future slope movement but to confine potential failure surfaces to a region of the slope well below the roadway bench and extending out to the slope face such that a failure surface does not extend up onto the roadway bench. This design results in movement along the roadway bench that is more uniform and less disruptive to traffic. This paper describes the results of a study to evaluate the DPERG technique by analytical methods supported by field observations for the purpose of determining the required depth of the DPERG and the optimum layer spacing of the reinforcement. The study showed that for a given slope geometry and set of soil properties that had led to failure in an unreinforced slope, there were several combinations of DPERG depth and number of reinforcement layers that satisfied the design goal. The study showed that more tightly spaced reinforcement layers were beneficial and that for widely spaced layers, the design goal of a DPERG could not be met, even for a thick DPERG depth.