Corrosion-induced deterioration of steel RC highway bridges is one of the major distress types that can render a structurally deficient bridge before reaching the design life. One feasible solution to the problem is to replace the conventional steel reinforcement with noncorrosive carbon fiber–reinforced polymer (CFRP) reinforcements. However, the CFRP reinforcement as an internal reinforcement has not been explored in AASHTO-type prestressed concrete beam bridges. AASHTO-type beams have an I-type cross section with a bottom flange, and on integration of the deck slab, the final shape is a bulb-T section. This paper discusses the experimental investigation of a precast prestressed AASHTO control beam and a bridge model. A 12.5-m-long one-third scale AASHTO-type control beam was experimentally investigated for its flexural behavior when reinforced and prestressed with CFRP. Subsequently, a one-third scale bridge model made of five such beams was constructed, instrumented, and tested under both serv...

The State of Michigan in the United States often encounters weak soil subgrades during its road construction and maintenance activities. Undercutting has been the usual solution, while a very few attempts of in-situ soil stabilization with cement or lime have been made. Compared to the large volume of weak soils that require improvement and the cost incurred on an annual basis, some locally available industrial byproducts present the potential to become effective soil subgrade stabilizers and a better solution from the sustainability perspective as well. The candidate industrial byproducts are Cement Kiln Dust (CKD), Lime Kiln Dust (LKD), and Fly Ash (FA), out of which only a fraction is currently used for any other secondary purposes while the rest is disposed of in Michigan landfills. This manuscript describes a laboratory investigation conducted on above industrial byproducts and/or their combinations to assess their suitability to be used as soil subgrade stabilizers in three selected weak soil types often found in Michigan. Results reveal that CKD or a combination of FA/LKD can be recommended for the long-term soil subgrade stabilization of all three soil types tested, while FA and LKD can be used in some soil types as a short-term soil stabilizer (for construction facilitation). A brief discussion is also presented at the end on the potential positive impact that can be made by the upcycling of CKD/LKD/FA on sustainability.

The effective temperature difference between the slab's top and bottom at time of final set is an important input parameter for the recently developed mechanistic-empirical pavement design guide (M-EPDG). However, very limited guidelines are available for the selection of this parameter. The major focus of this work is to quantify built-in curl from field temperature measurements for Michigan pavements. The results of this study show that built-in curl can be substantial for hot weather paving conditions. Early morning paving on a sunny summer day allows a maximum positive (i.e. top warmer than bottom) temperature difference at time of final set due to maximum heat of hydration and added solar radiation effects. The temperature difference between the slab's top and bottom was found to be 10–12°C. Consequently, the slab stays flat and in full contact with the base from this time only if this range is maintained. Unfortunately, this only occurs for a short time-period near mid-day, so the slab is mostly in a permanently upward curled condition. For late fall temperature conditions, the difference was slightly negative (about − 2°C) at time of set. Late fall construction therefore is favorable for maintaining slab–base contact. Despite combined built-in curl and daily curling changes, slab stress predictions using finite element analysis (ISLAB2000) for multi-axle loading at joints found the total stresses for a typical summertime 24 h period to be below the tensile stress necessary to initiate fatigue failure (i.e. below 45% of the flexure strength). This suggests that additional slab uplift from moisture warping is a factor for top–down cracking to develop.

The construction industry presents significant high risks of injury and fatality to its workforce. Adopting prevention through design (PtD) principles is reported to have high potential for mitigating such risks and improving safety outcomes. PtD seeks to assess and reduce workplace hazards during the design phase, minimizing unsafe construction conditions. Despite its potential benefits, the construction industry encounters challenges in effectively utilizing PtD. Thus, the implementation of PtD in the US construction industry is limited, and designers’ awareness remains low. This evident lack of utilization warrants further examination of the contributing factors. The goal of this study is to identify and rank PtD utilization barriers in the United States (US) construction industry. This study pinpointed 12 pivotal barriers to PtD implementation through a systematic literature review. These barriers were categorized into industry-, project-, designer-, and client-related domains. Furthermore, they were grouped into three clusters based on their influence on PtD implementation from the most to the least influence, based on an expert matter questionnaire. This study also compared the experts’ rankings of the identified barriers with their citation frequencies in the reviewed articles. Among other observations, this study found that the lack of PtD professional training and formal education for project stakeholders negatively impacts the likelihood of PtD utilization and exacerbates several other barriers. Therefore, it is advisable to prioritize addressing this barrier by allocating the necessary resources and efforts to efficiently address it. Construction industry stakeholders with a vested interest in advancing PtD applications are encouraged to leverage the insights this study provides to expedite the adoption of PtD.

Remove-and-replace with suitable material has been the primary solution used for improving subgrades in Michigan, USA, when weak subgrades are encountered in road construction. Considering the large extent of silty and clayey soils found in southeastern Michigan, where much of the population and the roads are located within the state, the earthwork associated with this solution is massive and expensive. The use of cement kiln dust (CKD) or lime kiln dust (LKD) as a subgrade stabilizer can be a cost-effective solution if there is sufficient evidence to prove that such stabilization is suitable for the soils and the climate in southeastern Michigan. This became the subject of a field and laboratory investigation carried out in Michigan and sponsored by the Michigan Department of Transportation. The findings from the laboratory portion of this research (which were published in a separate manuscript) proved CKD’s suitability for long-term stabilization and LKD’s capacity for being a stabilizer for short-term modifications of clayey soils found in southeastern Michigan. This study covers the field testing portion of this investigation. Two CKD-stabilized and another two LKD-stabilized subgrades, which were already in use for 4–6 years, were tested for strength, using dynamic cone penetration (DCP) tests. The California bearing ratios estimated from the DCP tests showed that the CKD-stabilized and LKD-stabilized subgrades could offer strength gains as high as 200–515% and 149–257% compared to in situ soils, respectively, even after 4–6 years in use.