Cement Lime Research Articles

Can mussel shell waste optimize cement and air lime mortars hygrothermal performance?

Mussel shells used as aggregates for mortars have flaky and irregular particles, which significantly increases the pore volume. This leads to the identification the microstructure of mussel shell mortars as a light and porous composite, which could have good hygrothermal properties. In the present study, the density and thermal properties are assessed on cement and air lime mortars, each with three replacement percentages of replacement of conventional sand by mussel shell sand (25 %, 50 % and 75 %), are evaluated and compared with their respective baselines (0 % replacement). Thermal conductivity measurements are also carried out on different loose fractions of the mussel shell aggregate to understand the behaviour of this material without binder matrix. Finally, adsorption and desorption cycles at 80 % and 50 % relative humidity are carried out on loose aggregate fractions and on the eight mortars. The results are very positive for the mussel shell mortars, as it can be concluded that the use of mussel shell aggregates improves the thermal performance and the potential moisture buffering capacity of both cement and air-lime coating mortars.

Dissolution Behaviors of Recycled Cement Paste and Lime in EAF Slag Under Static Conditions

AbstractRecycled cement paste (RCP) is a CaO-rich resource that is recycled from waste concrete and waste cement. For reducing environmental impact and promoting comprehensive resource utilization, RCP could partially replace lime as flux in electric arc furnace (EAF) steelmaking process. In this study, the dissolution behaviors of RCP and lime in EAF slag at 1400 °C and 1500 °C were investigated using static dissolution experiments. The measured dissolution rate constant of lime at 1400 °C and 1500 °C is 3.12×10−5 and 8.42×10−5 m/s, respectively, while that for RCP is 1.37×10−4 and 2.91×10−4 m/s, respectively. For the lime dissolution, a dense dicalcium silicate (C2S) product layer was generated at the dissolution interface, with the diffusion of Ca2+ in the C2S layer being the limiting step for the lime dissolution. However, for the RCP dissolution, no product layer was observed at the dissolution interface. Instead, a dissolution intermediate layer forms due to slag penetration. During the dissolution of RCP, Ca2+ and SiO44− diffuse from RCP layer to slag, while Fe2+ and AlO45− diffuse from slag to RCP layer accumulating in the dissolution intermediate layer. Furthermore, a dissolution model was developed based on current experimental results, which helps to predict dynamic dissolution process of lime and RCP in EAF slag. In general, the dissolution rate of RCP in EAF slag was much higher than that of lime, partially adding RCP as flux in EAF could accelerate the liquid slag formation in EAF steelmaking process.

Multi-Factor Orthogonal Experiments and Enhancement Mechanisms of Unconfined Compressive Strength of Soda Residue Cement Lime Soil

In order to study the effects of soda residue content, particle size, moisture content, and curing age on the unconfined compressive strength (UCS) of soda residue cement lime soil (SRCLS), a 4-factor, 4-level orthogonal experimental design was employed in this study. Different conditions of SRCLS UCS and their impacts were tested and analyzed. The internal microstructure and hydration products of SRCLS were studied using SEM and XRD to explore the strengthening mechanism of SR in SRCLS. The results indicate that as the soda residue content gradually increased, SRCLS UCS initially increased and then decreased, with a maximum increase of up to 67%. With increasing soda residue particle size and moisture content, the UCS of SRCLS gradually decreased. The optimized mix ratio was determined to be soda residue:cement:lime:soil = 3%:3%:6%:100%, with the soda residue dried naturally and an ideal particle size of 0.15 mm. The factors influencing the unconfined compressive strength (UCS) of SRCLS, in order of importance, are curing age, soda residue content, moisture content, and particle size of SR. Among these, curing age and soda residue content have a significant impact on the UCS. An adequate amount of SR can act as a fine aggregate filler, replace lime, promote cement hydration, and enhance chloride ion binding. This improves the grading of SRCLS materials and facilitates the formation of cementitious products from AFm, AFt, and Friedel’s salt, resulting in denser and stronger SRCLS materials. The research findings provide a reference for the mix design of SRCLS and the large-scale utilization of waste soda residue.

Hydraulic activity of crushing screenings of waste open-hearth slag

Theoretically and experimentally studied the hydraulic activity of crushing screenings of waste open-hearth slag and methods for intensifying the hydration hardening of slag stone during operation. During the hardening of slag stone, three periods of pronounced syneresis with gel new formations strengthening the material were established at the ages of 28 – 60, 90 – 180 days and 1 – 2 years. The first period of syneresis, in contrast to the subsequent ones without changing the strength of the samples, is recorded by the linear shrinkage of the samples, the squeezing out of bound water and the increase in pH. The introduction of two percent of cement dust or lime into the crushing screenings of waste open-hearth slag leads to the strengthening of the slag stone at 28 and 90 days of age by 3 – 4 times. However, by the age of two years, the strength of the samples stabilizes. This fact indicates that the additions of cement dust or lime are not additional binders, but hardening accelerators.

The Effect of Using Sustainable Copper Fiber on Some Mechanical Properties of High Strength Green Concrete

Finding an alternative to materials that pollute during manufacturing, most notably cement, is vital to executing the idea of sustainability in the building sector. It was vital to develop concrete that assists in the reduction of CO2 (Carbon dioxide) in the atmosphere because industrial wastes contain calcium, silica, and aluminous minerals, such as silica fume, that are employed in the production of high-strength concrete and have parameters that are identical to those of regular concrete. As a substitute for Portland cement, lime cement was utilized, and 15% of the cement's weight was substituted with silica fume. Environmentally friendly fibers (Copper Fiber) created from old electrical and electronic equipment were also employed. The purpose of the study is to produce High Strength Green Fiber Concrete (HSGFC) by incorporating silica fume as a replacement and study the effect of adding fiber on some mechanical attributes. The task needed the creation of a high strength concrete mixture of cement with a compressive strength of 65 MPa in accordance with ACI 211.4R, as well as the development of numerous experimental mixtures that relied on the findings of earlier researchers. The mechanical properties (compressive strength, flexural strength and split tensile strength) of samples are tested at 7, 28 and 60 days with standard curing. The results show that adding sustainable fiber to concrete mix enhances the mechanical properties such as compressive strength by 16% at 28 days, flexural strength by 35% and spilt tensile strength by 44% at 28 days Compared with concrete mix with no fiber. Also, the outcomes showed that it is feasible to develop High Strength Concrete (HSC) using sustainable copper fiber possessing exceptional stress resistance, tensile strength, and flexural strength.

Resisting Material Binaries: Unpacking persisting dichotomies of building materials in Central Africa

The current discourse on African architecture is strongly influenced by social design—a practice for which architecture holds an important role in addressing complex societal questions and problems. The use of “alternative” building materials, as opposed to industrial materials like concrete or steel, is very central within this discourse. However, as this article argues, this strong binary approach to building materials is heavily influenced by colonial and postcolonial logic. To understand this continuity, I will trace some path dependencies visible in the Central African region from the colonial period to the present. In the first section, the material preferences of a Belgian architecture firm working in Rwanda in 2012 are related to the binaries of the architecture firms operating in this region in the 1970s and 1980s. In the second section, I discuss how the strong distinction between so-called “local” and “modern” materials is a remnant of the colonial period. Through an in-depth analysis of the shifting valuations of cement and burnt lime in Central Africa, the article aims to make these colonial categories feel less natural. Building on post-colonial science and technology studies (STS) scholarship, the conclusion proposes an alternative to binary thinking—a conscious material choice that tries to understand building materials as situated processes, allowing to go beyond the industry-driven denominators by which we currently value our building materials.

On the necessity of new hydrophobic treatment after repointing of water repellent masonry

The impregnation of the exterior surface of a masonry wall with a water repellent is a common intervention in (historic) building renovation and maintenance. Such treatments, whilst degrading at the surface with time under influence of ultra violet light, remain effective below the surface several decades after their application. During renovation works of masonry previously treated with a water repellent, the question arises whether it is necessary to repeat the hydrophobic treatment of the entire masonry after repointing. Opposing opinions exist with this regard, but no research clearly supporting one or the other. This research investigates for the first time the effect of hydrophobic treatment when applied on previously treated and repointed masonry walls. Small masonry walls were subjected to rain periods in the laboratory and their water uptake and drying behaviour were studied. Moreover, this laboratory research was followed by 30 months of outdoor exposition of the masonry specimens. The following cases were considered: (1) wall treated with water repellent, (2) wall treated with water repellent, followed by repointing but without new water repellent treatment, (3) wall treated with water repellent, followed by repointing and retreatment. This was done for three different types of pointing mortar: ordinary Portland cement and natural hydraulic lime with standard sand, and natural hydraulic lime with sand with one grain size. The results show that, after prolonged rain periods, the water uptake by repointed but not retreated masonry is comparable to that of untreated, non-hydrophobic masonry, whereas drying is considerably slower. This leads to a high saturation degree in repointed but not retreated masonry, which, in turn, increases the risk of damage to the masonry by e.g. frost. Therefore, retreating repointed hydrophobic masonry should definitively be considered.

Development of mathematically motivated artificial intelligence models for the prediction of carbonate rock lime saturation factor for cement production

Predicting the cement lime saturation factor (LSF) is vital in cement production as it determines the optimal ratio of lime to other components. This factor affects the quality and strength of concrete, enabling efficient resource utilization, cost control, and environmentally sustainable practices in construction and infrastructure projects. The laboratory tests to determine the elemental composition of cement material is time-consuming and costly. However, limited research has suggested that there is a correlation between parameters obtained from elemental and proximate analyses of these materials. In this study, some predictive models of the elemental composition of carbonate rock using soft computing and regression analyses have been developed from chemical database from 7 formations in Nigeria. These formation includes carbonate deposit in Ikpeshi (Edo State), Ubo River area (Edo State), Itobearea (Kogi State), Igarra (Edo State), Nsofang (Ikom) Igue (Edo State), and Ewekoro (Ogun State). One hundred and forty-four (144) samples including parameters of elemental and proximate analyses were used during the analyses to develop multiple prediction models. Dependent variables for multiple prediction models were selected as carbon, hydrogen, and oxygen. Using Calcium oxide, magnesium oxide, loss of ignition, and the ratio of calcium oxide to magnesium oxide as independent variables, three different prediction models were developed for LSF as the dependent parameter using multilayer perceptron (MLP), least square support vector machines (LS-SVM), Multivariant regression (MVR) and hunter point Backpropagation-artificial neural network (HPBR-ANN) techniques. In addition, a routine for selecting the best predictive model was suggested in the study. The reliability of the established models was tested by using various prediction performance indices and the models were found to be satisfactory. Therefore, the developed models can be used to determine the cement production lime saturation factor of carbonate rock for practical purposes.

The Effect of Using Different Aspect Ratios of Sustainable Copper Fiber on Some Mechanical Properties of High-Strength Green Concrete

To achieve sustainability, use waste materials to make concrete to use alternative components and reduce the production of Portland cement. Lime cement was used instead of Portland cement, and 15% of the cement's weight was replaced with silica fume. Also used were eco-friendly fibers (copper fiber) made from recycled electrical. This work examines the impact of utilizing sustainable copper fiber with different aspect ratios (l/d) on some mechanical properties of high-strength green concrete. A high-strength cement mixture with a compressive strength of 65 MPa in line with ACI 211.4R was required to complete the assignment. Copper fibers of 1% by volume of concrete were employed in mixes with four different aspect ratios (20, 40, 60, and 120). At 7, 28, and 60 days after typical curing, the samples' mechanical characteristics (compressive strength, flexural strength, and split tensile strength) are assessed. A reported increase in compressive strength of (2, 1.6, and 1.4) in (7, 28, and 60 days) for concrete with a high aspect ratio 120, compared to concrete with a low aspect ratio 20. The flexural strength of high-strength green concrete with fibers of a higher aspect ratio 120 was (23, 11, and 12.6%) times higher for all ages compared to low aspect ratio 20. The split tensile strength rose (1.7, 1.5, and 1.6%) for (7, 28, and 60 days), respectively, for concrete with a high aspect ratio 120, compared to concrete with a low aspect ratio 20. It was found that using fibers with a large aspect ratio improved the mechanical properties of concrete more than fibers with a small aspect ratio.

Mineralogy and Geochemistry of Anah and Euphrates Formations and Their Suitability for Portland Cement and Noora Industry at Al-Baghdadi and Haditha Areas, Western Iraq

The current study including geochemical and mineralogical aspects of 12 rock samples from Anah and Euphrates formations in two outcrops, The first outcrop is at Haditha city, with 12.5 meters thickness, and the second location is at Al-Baghdadi city, with 21 meters thickness. The mineralogical study by X-ray diffraction indicated that calcite is the main mineral in the rocks of Anah Formation, while calcite and dolomite exist in Euphrates Formation, where calcite is concentrated in the lower part of Euphrates Formation, while dolomite is common in the middle and upper parts of this formation, in addition to other minor minerals such as quartz and feldspar. Geochemical study was carried out by XRF to determine the major oxides(CaO, MgO, Fe2O3, Al2O3, SiO2, SO3, K2O, Na2O, MnO) and the suitability of Anah and Euphrates rocks as raw material for Portland cement and Al-Noura (lime) cement industries. According to the results it is found that Euphrates Formation in the Al-Baghdadi and Haditha outcrops is not suitable for the Portland cement, because of high percentage of MgO as a result of the high percentage of dolomitic limestone. The chemical analysis of the samples of the Anah Formation in Haditha outcrop are suitable for the Noura cement (lime) industry according to the Iraqi standard. The high content of magnesium in the Euphrates Formation at Al-Baghdadi area used as indicator that the rocks deposited in shallow marine and warm condition, and the environment was mostly isolated with warm condition. Low Sr content indicates shallow carbonate rocks. Thus, the sedimentary environment of the Anah Formation at Haditha outcrop was relatively shallower than that of the Euphrates Formation.

Influence of Lime on Strength of Structural Unreinforced Masonry: Toward Improved Sustainability in Masonry Mortars

The choice of a sustainable construction material needs to take into account not just the environmental impact of the material, but according to the 2030 Agenda for Sustainable Development by the UN, one also needs to consider ease of access, the utilization of locally available materials, and the durability and reliability of the construction itself. Mortared masonry has been used around the world for several hundred years as an accessible type of construction. In masonry mortars, lime and cement are often integrated together for combined advantages: enhanced workability, breathability, and better environmental performance due to the former, and higher strength and shorter setting duration due to the latter. However, despite being extensively studied for their effects on the mechanical properties of mortar, not much is known about the impact of varying lime and cement ratios in the binder on the mechanical performance of masonry as a whole. Variations in the properties of mortars do not always have a significant impact on the mechanical behavior of masonry structures. Therefore, this article details an experimental campaign to measure the compressive strength, E-modulus, flexural strength, and shear bond strength of masonry samples containing two distinct lime–cement mortars (1:2:9 and 1:1:6 cement:lime:sand) and one cement mortar (1:0:5). The results show that more than the presence of lime in the mortar, the strength of the mortar influenced the flexural strength of the masonry ranging from 0.1 to 1.2 MPa. No discernable correlation was observed between the presence of lime in the mortar and the cohesion in the masonry (0.29 to 0.41 MPa). The values of the compressive strength (6.0 to 7.2 MPa) and E-modulus (3.8 to 4.5 GPa) of the masonry decreased and pre-peak ductility increased with an increase in the quantity of lime in the mortar. The recommendations of Eurocode 6 for the flexural strength of the initial shear bond strength were found to be conservative for different mortar strength classes, and significantly unconservative for compressive strength (by 50% to 70%).

Prediction of unconfined compressive strength of cement–lime stabilized soil using artificial neural network

Prediction of unconfined compressive strength of cement–lime stabilized soil using artificial neural network

Assessment of the sustainability and producibility of adobe constructions reinforced with Ca-based binders: Environmental life cycle analysis (LCA) and 3D printability

This study investigated the usability of adobe samples reinforced with calcium-based binders in a 3D-printed technique. These adobe samples' physical, mechanical, durability and microstructure characteristics were investigated and their 3D printability characteristics experimentally. In the case of adobe production by 3D-printing method, the compressive strength decreased by 9–33 % compared to mold casting. While the thermal conductivity coefficient of adobe samples varied between 0.833 and 1.421 W/mK, the thermal conductivity was reduced by 43 % thanks to the preference for gypsum. Within the scope of the LCA analysis, the slightest effect in terms of environmental damage was observed in mixtures containing gypsum compared to cement and slaked lime mixtures. As a result, it was determined that adobe's physical and mechanical characteristics could be improved by using gypsum, lime and cement, and these mixtures can be used in 3D-printing. It was determined that more sustainable adobe production is possible with gypsum and lime.

20th Century Mortars: Physical and Mechanical Properties from Awarded Buildings in Lisbon (Portugal)—Studies towards Their Conservation and Repair

This paper addresses the study of renders and plasters’ physical and mechanical characteristics from selected buildings awarded during the 20th century with a renowned architectural prize in Lisbon, Portugal. The characterisation was done to understand mortars’ physical and mechanical properties and their evolution during the 20th century. These characteristics will also help determine compatibility requirements for future conservation and restoration interventions. Since these buildings have a heritage great interest status, the need to preserve them is a paramount issue. Fifty-three samples from nine case studies were studied via capillary water absorption, drying rates, open porosity, dynamic modulus of elasticity, and compressive strength. There were limitations in sample collection due to the buildings being in service and technical constraints regarding sample quantity for testing and separating layers of the multi-layer mortar system. Nevertheless, the results showed different ranges of quantitative values for these tests, whether the mortars were lime, gypsum, cement-based or had lime–cement blended formulations.

Properties of cement–bentonite mortar developed by mineral additives for primary firm secant pile by Taguchi method

To make construction materials more sustainable and greener, companies must consider the environmental impact when sourcing materials include developing methods for sustainable recycling and encouraging design practices that prioritize the use of green materials using additives. Geotechnical applications including construction of cutoff walls require development of enhanced materials that possess certain attributes to ensure strain compatibility with surrounding soil. The study aims to explore the utilization of different materials such as bentonite, cement dust, fly ash, lime and polypropylene fibers to produce cement–bentonite mortar with low permeability and sufficient strength. For optimizing the process parameters in the experimental domain, an orthogonal array by Taguchi method was used, and thirty-two experimental runs were performed. The properties investigated included flow%, displaced volume rate, compressive, splitting tensile, flexural, shear strengths, elastic modulus and permeability coefficient. The test results demonstrated that cement dust, fly ash and lime could achieve optimal performance in terms of low permeability and sufficient strength. Additionally, polypropylene fibers up to 0.3% could be effectively used to achieve sufficiently low elastic modulus without affecting other conductive strengths significantly. The findings of the regression model demonstrated that the developed models could account for how the independent variable affected the necessary responses. This study could provide engineers with insights into selecting the appropriate materials to achieve the desired performance characteristics for some geotechnical applications considering sustainability.

Mechanical Properties of Polyamide Fiber-Reinforced Lime–Cement Concrete

Lime–cement concrete (LCC) is a type of lime-based concrete in which lime and cement are utilized as the main binding agents. This type of concrete has been extensively used to construct support layers for shallow footings and road backfills in some warm regions. So far, there has been no systematic research conducted to investigate the mechanical characteristics of polyamide fiber-reinforced LCC. To address this gap, LCC specimens were prepared with 0%, 0.5%, 1%, and 2% of polyamide fibers (a synthetic textile made of petroleum-based plastic polymers). Specimens were then cured for 3, 7, and 28 days at room and oven temperatures. Then, the effects of the fibers’ contents, curing conditions, and curing periods on the mechanical characteristics of LCC, such as secant modulus, deformability index, bulk modulus, shear modulus, stiffness ratio, strain energy, failure strain, strength ratio, and failure patterns, was investigated. The results of the unconfined compressive strength (UCS) tests showed that specimens with 1% fiber had the highest UCS values. The curing condition and curing period had significant effects on the strength of the LCC specimens, and oven-cured specimens developed higher UCS values. The aforementioned mechanical properties of the LCC specimens and the ability of the material to absorb energy significantly improved when the curing period under the oven-curing condition was increased, as well as through the application of fibers in the mix design. Based on the test results, a simple mathematical model was also established to forecast the mechanical properties of fiber-reinforced LCC. It is concluded that the use of polyamide fibers in the mix design of LCC can both improve mechanical properties and perhaps address the environmental issues associated with waste polyamide fibers.

Investigation of Durability Properties for Lightweight Structural Concrete with Hemp Shives Instead of Aggregate

The paper presents the results of testing the performance of lightweight structural concrete containing hemp shives as an aggregate. It has been analysed how the higher binder content and use of the Portland cement affect the thermal and microbiological properties of the lightweight concrete. The aggregates of the plant origin and cement are incompatible because the plant chemical compounds, dissolved in water or an alkaline environment, inhibit cement hydration. To avoid this, mineralisation of the aggregates of plant origin is necessary. The most often used binder in hemp concrete is hydrated lime, a mineraliser. An addition of hydrated lime and sodium trisilicate was used for hemp shiv mineralisation in the tested materials with a cement binder. Concrete containing hemp shiv and cement binder, of which volume share in the concrete was at most 15%, was prepared as a reference concrete. In the remaining three concretes, the total content of the binder in relation to hemp shiv (by mass) was increased 2.5 times. It was shown that lime-binder hemp concrete offers a promising antimicrobial strategy, as it can inhibit bacterial and fungal growth on their surface with superior efficacy. The best results were obtained for tested concretes with the cement–lime binder regarding compressive strength; the average compressive strength was 9.56 MPa.

DESTRUCTION OF POLYMERCEMENT PLASTER COATING DURING OPERATION OF WALL STRUCTURE

The disadvantage of limesand, limecement and cementlime plaster mortars is the intensive formation of cracks during hardening and operation, which leads to rapid destruction of the plaster coating, its detachment from the masonry, which causes increased humidity and loss of heat through it, as well as reducing the service life of the wall structure.The main reason for this is choosing the components of the mixture and their quantity without taking into account the processes occurring during curing of the coating and its "work" as part of the wall structure during operation.To solve the problem, the wall structure should be considered as a system that includes a plaster coating associated with the masonry through the contact area. The composition of the soluble mixture must be prescribed taking into account the processes occurring during its hardening and operation of the wall structure, the stresses that occur in it. It is necessary to choose the components of the mixture and their quantity, so as to ensure the reduction of stresses in the plaster coating and its contact zone with the masonry, to values, less than destructive. This will increase the service life of the coating and wall construction.Since the properties of polymercement plaster mortar are determined by its composition and structure, to achieve these goals, the possibility of managing them by purposeful selection of components of the soluble mixture was analyzed. For this purpose, redispersible polymer powders (RPP), polymer fiber, cellulose esters, and a fine filler with a low modulus of elasticity were used.Studies have shown that their use has changed the nature of the destruction, reduced the number of cracks formed during the hardening of the plaster mortar, slowed down their development and increased the service life of plaster mortar and the wall structure.

POLYNOMIAL MODELS FOR PREDICTING TIME LIMITS FOR COMPACTION AFTER MIXING OPERATION OF LATERITIC SOIL REINFORCED USING CEMENT OR LIME

The demand for natural aggregates has increased in recent years because of diverse environmental interests. Consequently, its cost has soared astronomically and the utilization of lateritic soil for low-cost roads has been an attractive option. In most cases during road construction, unprecedented conditions may lead to delays in the compaction of the treated soil after the mixing operation and placing had taken place. Thus, this study developed polynomial models for predicting time limits for compaction after mixing operation within 0-180 minutes at 30 minutes intervals for lateritic soil reinforced with cement and lime. The percentage contents by weight of the dry soil for cement or quick lime mixed with the soil were 2, 4, 6, 8 and 10%. Consistency indices tests and particle size analysis were carried out on the untreated lateritic soil for characterization. The tests conducted on the lateritic soil prepared with cement and quick lime were compaction test (Standard Proctor), California Bearing Ratio (CBR) and unconfined compressive strength (UCS) of 7 days curing. The AASHTO soil classification system and Unified Soil Classification system rated the lateritic soil to be A-6(13) and clayey soil (CL), respectively. Ordinarily, the lateritic soil was found to be a poor construction soil and therefore requires treatment to improve its strength in order to make it useful for pavement purposes. At the increase in time limits for compaction after mixing, there were reductions in compaction and strength characteristics of the lateritic soils that were prepared with cement or lime. The polynomial models developed were a good fit for predicting time limits for compaction after mixing using cement/lime contents, compaction and strength characteristics of the strengthened soil. The polynomial models gave coefficients of correlation and determination of 0.988 and 0.976, respectively, when the soil was prepared with cement whereas, in the case of lime-prepared soil, the values were 0.966 and 0.933, respectively. The cement/lime contents, optimum moisture content (OMC), CBR and UCS (7 days curing) were entirely statistically significant in predicting time limits for compaction after mixing at a 95% confidence level.

Using Kiln Dust to Improve Weak Subgrades for Pavement Construction: A Field Verification in Michigan, USA

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.