Degradation of roller compacted concrete subjected to low-velocity fatigue impacts and salt spray cycles

Mechanistic and microstructural characteristics of roller-compacted concrete (RCC) produced from recycled asphalt pavement (RAP) and geopolymer cement binder (GPC) were evaluated and compared with mixtures produced from ordinary Portland cement (OPC). It was found that RCC using geopolymer binder exhibited higher unconfined compressive strength, modulus of elasticity, and flexural strength as compared to the mixture containing ordinary Portland cement. It was also discovered that the mechanical properties of the developed concrete depend on mixture constituents: sodium hydroxide molarity, the ratio of sodium silicate to sodium hydroxide, curing temperature, and gradation of RAP. The experimental results showed that RCC using geopolymer binder exhibited compressive strength, modulus of elasticity, and flexural strength in the range of 8.4–21.1 MPa, 18.3–35.0 GPa, and 2.9–4.1 MPa, respectively. On the other hand, RCC using 12% OPC presented similar mechanical strengths of 13.2 MPa, 32.8 GPa, and 3.32 MPa, respectively. Regression analysis was also performed to establish the relationship between mechanical characteristics and various mixture constituents. Morphological and microstructural analysis proved the formation of geo-polymeric compounds. Based on the mechanistic characteristics, the developed roller-compacted RAP-Geopolymer concrete could be used as a strong pavement base in composite pavement system or wearing course of low volume roads.

Roller-compacted concrete (RCC) offers a cost-effectiveness and ease of construction concrete pavement alternative. The use of waste materials into RCC pavement contributes to sustainable development with economic and environmental benefits. Traditional RCC mixture proportioning method does not objectively consider waste materials such as reclaimed asphalt pavement (RAP) or crumb rubber and thus may not meet performance criteria. Numerous statistical and robust design methods have been used for optimising the design of concrete mixture. However, the available methods cannot satisfy practical requirements for concrete mixtures incorporated waste materials. This methodology is unique in that it is specifically designed to focus on mixtures containing RAP and crumb rubber. In this paper, a statistical method called Taguchi is applied to optimise the mix design of RCC mixtures incorporated RAP and rubber materials. Parameters such as compressive and flexural strengths, density and toughness index are selected to study RCC performance characteristics. The best possible levels of mix proportions are determined for maximising compressive and flexural strength with considering the toughness property. These optimal values in the preparation of RCC specimens are determined experimentally. In addition, an analysis of variance (ANOVA) is performed on RCC parameters such as flexural and compressive strengths and toughness index.

The evaluation of calcium carbonate added and basalt fiber reinforced roller compacted high performance concrete for pavement

With increasing demand for more sustainable pavement options, roller-compacted concrete (RCC) is attractive because of its lower cement contents, construction expediency, and early opening to traffic. Addition of recycled aggregates to RCC can further economize this pavement type. The objective of this study was to determine the effects of the following recycled aggregates on RCC mixture design and hardened properties: recycled concrete aggregate (RCA), electric arc furnace (EAF) slag aggregates, reclaimed asphalt pavement (RAP), and steel furnace slag fractionated reclaimed asphalt pavement (SFSFRAP). For each mixture, compressive, split tensile, and flexural strengths and fracture properties were tested at multiple ages. The strength of the RCC containing recycled aggregates was similar to or lower than the RCC with virgin except for the RCC mixture with EAF, which produced statistically greater compressive strength. As expected, RAP and SFSFRAP resulted in lower compressive strengths compared to the virgin aggregate RCC. All RCC mixes with recycled aggregates had statistically lower flexural strength to RCC with virgin aggregates except the EAF aggregates. Disk compact tension fracture testing demonstrated that all recycled aggregate mixes had similar or greater values of critical stress intensity factor and total fracture energy relative to the virgin RCC. Based on past slab testing of concrete with recycled aggregates that had similar or greater fracture parameters relative to virgin aggregate concrete, slab flexural capacities are anticipated to be similar for RCC with and without recycled aggregates despite the lower strength properties for RCC containing recycled aggregates except the EAF aggregates.

Roller compacted concrete (RCC) has been gradually getting the preference for many pavement applications as a cost-effective, rapid, and durable construction material. Prior studies on RCC pavement already established that a thin RCC pavement can provide adequate structural performance if constructed cautiously. Nevertheless, many of the existing studies emphasized that fatigue behavior of RCC should be examined thoroughly since the most common failure mechanism of RCC pavement resulted from fatigue cracking. Over the years, researchers have made careful investigations to explain the fatigue behavior of RCC pavement when compared to conventional concrete pavement. However, a considerable part of these studies investigated the fatigue behavior mostly based on laboratory compacted beam or slab specimens and was quite incapable to consider the variability due to field construction procedure. Additionally, still, now pavement designers use either AASHTO 1993 empirical procedure or existing rigid pavement ME design protocols and thermal properties to implement RCC pavement application as there is no fully developed mechanistic-empirical (M-E) pavement thickness design procedure established for RCC pavement. In this study, a comprehensive beam fatigue test experiment was performed using field saw-cut RCC beam samples from accelerated pavement testing (APT) sections in the Pavement Research Facility (PRF) of Louisiana Transportation Research Center (LTRC) to investigate the fatigue behavior of in situ RCC pavements. In total 68 beams were prepared and tested from the field that marked this work as the first research study to explore the fatigue behavior of field RCC beam specimens prepared/constructed with a high-density asphalt paver and a vibratory roller. The results indicated that a well-compacted RCC pavement can achieve higher flexural strength and exhibit better fatigue life than conventional concrete pavement. This study also observed a strong linear positive correlation (R2= 82%) between the static flexural strength and laboratory-measured density of field specimen while inspecting the field pavement structure and compaction variability. Based on the beam fatigue test results, a RCC fatigue-life (S-N) prediction model was developed, and a reliability component was incorporated to provide a more reliable solution for designing RCC pavement thickness. Fatigue strength, that is defined as the unlimited fatigue life of RCC beams, was observed to be 65% of the static flexural strength. Simultaneously, in-situ strain responses and thermal properties (ie. coefficient of thermal expansion, temperature profile along with the slab depth) necessary for pavement design were also explored resulting from Accelerated Pavement Testing (APT). All the findings of this study, including

The worldwide use and implementation of roller compacted concrete (RCC) is growing because of its good technical and economic advantages especially here in turkey. Chemical admixtures basically used for conventional concrete to increase its strength and produce a good quality concrete, and there are so many companies produce chemical admixtures for conventional concrete but only few companies produce chemical admixtures for roller compacted concrete (RCC). We were able to find the only company in turkey “Lyxor” to produce chemical admixtures for RCC; meanwhile this research aims to dictate the effectiveness of some chemical admixtures for roller compacted concrete (RCC) mixtures. We have conducted a test method to characterize some of the properties of RCC and these include the compressive strength and flexural strength with direct shear test. In this research we have used mainly 2 different types of chemical admixtures which include 3 types of superplasticizers which are Nanoment SP – Superplasticizers, Nanoment MR – Midrange Plasticizer, Nanoment HP – New Generation Superplasticizers, and the other type is Nano Aer – Air Entraining chemical admixture. We have conducted the test method by preparing 3 different RCC samples using each chemical admixture and tested them constantly within 3 and 28 days comparing them with 3 different None-admixed RCC samples which was prepared with the same procedure, and in the final we have prepared the test result table of each and every sample and the comparison chart as well. In the last part some recommendations and suggestions for the use of these chemical admixtures are mentioned.

Roller-compacted concrete (RCC) is gaining recognition for its economic and structural benefits, particularly in heavy-duty pavements, dams, and industrial flooring applications. Unlike traditional concrete, RCC is a low-water, zero-slump mix that can be compacted with vibratory rollers, reducing cement usage, costs, and environmental impact. However, RCC's low water content raises significant curing problems that could compromise the strength, durability, and overall performance of the concrete. Conventional surface curing methods often prove inadequate, leading to incomplete hydration and undesirable concrete properties. This study explores an innovative approach to RCC production by incorporating clay tile waste as an Internal Curing Aggregate (ICA) to replace coarse aggregates. The aim is to improve hydration and enhance RCC's mechanical properties by addressing internal curing challenges. Clay tile waste, characterized by its porous structure and high-water absorption capacity, is proposed as a sustainable alternative to conventional aggregates, providing additional moisture during the curing process. This research investigates the effects of replacing coarse aggregates with clay tile aggregates (CTA) at 2.5% , 5%, and on RCC ’s mechanical and durability properties. The results show that a 2.5% replacement of coarse aggregates with CTA significantly improves early compressive strength, with notable gains observed at the 3-day mark. This early strength development is attributed to the effective internal curing provided by the tile waste, which facilitates continued hydration. At 28 days, RCC samples with 2.5% CTA replacement perform similarly to control samples in tensile strength, suggesting CTA's potential as an internal curing agent. Flexural strength tests further support these findings, with 2.5% CTA replacement yielding the highest strength among the tested samples. However, increasing the replacement ratio beyond 2.5% results in diminishing returns across all measured mechanical properties. This decline is likely due to the lower inherent strength of the clay tiles compared to traditional coarse aggregates. Results suggest that a 2.5% CTA replacement improves RCC's mechanical properties, supporting more sustainable construction. The study provides important insights into using waste materials for sustainable RCC production. Incorporating clay tile waste as an ICA improves internal curing, enhancing hydration, early strength, and overall RCC performance. These findings support the development of sustainable construction materials and provide practical recommendations for optimizing RCC mix designs. Future work will involve field validation of these results and further exploration of long-term durability aspects under different environmental conditions.

A huge volume of waste is generated by natural and human-made disasters and by rapid urbanization that leads to the demolition of structures reaching the end of their service life. Using recycled aggregates in concrete producing reduces environmental pollution by decreasing the disposal of this waste material in landfills and preserving unreasonable exploitation of natural resources. This manuscript presents the results of an experimental program aiming to study the effect of recycled aggregates on the physical and the mechanical properties of roller compacted concrete (RCC). A Dreux–Gorisse mix design method together with the modified proctor test were adopted to prepare a reference mixture with natural aggregates with three derived mixtures where coarse aggregates were replaced by 50%, 70%, and 100% of recycled aggregates. The physical properties of RCC were evaluated by means of water absorption and gas permeability tests while the mechanical properties were evaluated using compressive, tensile splitting and 3-point flexural tests. The results of physical tests showed that both water absorption ability and gas permeability increase proportionally with the replacement ratios. The results of the mechanical tests showed that the compressive strength class was approximately constant for all developed mixtures at the age of 28 days. For a substitution ratio of 100%, a drop in the compressive strength of only 6% was recorded. The reduction in the tensile and flexural strength was more pronounced than the compressive strength and was about 10% for the mixture of 100% recycled aggregates. It was found that the strength increases with time, and it can be estimated at any age using the analytical models adopted for conventional hydraulic concretes. Based on the obtained results, it was concluded that recycled aggregates up to 50% don’t negatively affect the physical and mechanical properties of RCC.

Integrating recycled asphalt pavement (RAP) into roller-compacted concrete (RCC) as a replacement for natural aggregates has recently emerged as a sustainable practice with significant environmental benefits. This study investigates the mechanical properties of RCC incorporating RAP aggregates, with a focus on developing a predictive model for its flexural and split tensile strengths. RCC mixtures with varying RAP content were developed and tested for compressive, split tensile, and flexural strengths. The results revealed a decline in composite performance with an increased RAP level. Nevertheless, mechanical strength met standard requirements for replacement rates of up to 60%. A new model was then developed, considering RAP rate alongside compressive strength, to predict the flexural and split tensile strengths of RCC. Existing models for conventional concrete were also evaluated for their applicability to RCC mixtures containing RAP. The proposed model demonstrated close alignment with experimental data from this study and other studies. It exhibited the lowest root mean square error, which confirms its accuracy in predicting the mechanical properties of RCC with RAP. This model provides a valuable tool for practitioners to estimate key parameters for designing pavement made with this composite.

Purpose: In this study, in order to produce sustainable roller compacted concrete (RCC) pavements, waste rubber tyres of different sizes, which pollute the environment and cannot be disposed of sufficiently every year, were used as coarse and fine aggregate substitutes to investigate the effects of waste rubber on the mechanical, durability and thermal properties of RCC pavements. Method: Waste rubber in three different sizes (shredded, crumb and powder) was replaced by aggregate at six levels (2.5%, 5%, 7.5%, 10%, 20% and 30%) with a maximum of 30% in SSB mixtures. The compressive, flexural and splitting tensile strengths as well as UPV, unit weight and modulus of elasticity were determined and compared with each other in order to investigate the mechanical properties of the SSB pavement mixtures with waste rubber composition. In order to determine the durability properties of SSB pavement mixtures containing waste rubber, the specimens were subjected to elevated temperature, freeze thaw, acid and sulphate effects. In addition, microstructural analysis was performed using scanning electron microscopy (SEM) to investigate the physical structure of SSB with waste rubber and its effect on concrete properties. In addition, using outdoor temperature data, modeling was performed by finite element analysis using the 3D software package ANSYS. With these models, the effects of waste rubber tires on the stresses caused by temperature changes in SSB pavements were investigated. Findings: In SSB specimens with 30% waste rubber content, 81%, 60% and 74% strength loss occurred in compressive, flexural and splitting tensile strengths, respectively, when compared to control specimens without waste rubber. Although it caused a decrease in strength, a mixture with a flexural strength of 4,96 MPa was obtained with the use of 20% waste rubber, making it possible to use them in pavements. In mixtures with 30% waste rubber content, 62%, 71% and 97% loss occurred in compressive, splitting tensile and flexural strengths after elevated temperature. In mixtures containing 30% waste rubber, a 21% loss in compressive strength occurred after 300 cycles of freeze thawing. After 180 days of acid effect, compressive strength loss was 55% in 30% waste tire-containing specimens, while compressive strength loss was 18% in 30% waste tire-containing specimens after 180 days of sulfate effect. With the partial replacement of coarse and fine aggregate with waste tires, a significant decrease of approximately 90% in the modulus of elasticity was determined. Results: The use of waste rubber in SSB instead of aggregate had a negative effect on the mechanical and durability properties of the mixtures. The increase in the amount of waste rubber resulted in the need for more water for the mixture and resulted in a 15% lighter mixture due to its low specific gravity and hollow structure. From a thermal point of view, the finite element analysis results show that the stresses in the pavement layer due to temperature differences decrease with increasing waste rubber content. Keywords: Roller compacted concrete, waste rubber, mechanical properties, durability properties, thermal analysis, finite element method.

The roller compacted concrete (RCC) dam has become one of the most competitive dam types due to its fast construction speed, low cost, and strong adaptability. However, the macroscale compaction test can hardly reflect the mesoscopic structure on the RCC’s rolling characteristics. According to the characteristics of RCC dam materials, a numerical discrete element method (DEM) is proposed in this paper, which is used to simulate the irregular shape and proportion of RCC aggregates. Moreover, a mesoscopic parameter inversion method based on the adaptive differential evolution (ADE) algorithm is proposed to enhance the efficiency of model contact parameters determination and overcome the inconvenience and time-consumption of conventional methods. Compared with the physical test, the simulation compression curve has good consistency with the physical test curve, and the proposed method can adequately reflect the physical and mechanical properties of RCC dam materials, which provides a basis for the subsequent research on the properties of RCC dam materials under different filling times.

This research aimed to investigate the mechanical and physical properties of Roller Compacted Concrete (RCC) used with Recycled Concrete Aggregate (RCA) as a replacement for natural coarse aggregate. The maximum dry density method was adopted to prepare RCC mixtures with 200 kg/m³ of cement content and coarse natural aggregates in the concrete mixture. Four RCC mixtures were produced from different RCA incorporation ratios (0%, 5%, 15%, and 30%). The compaction test, compressive strength, splitting tensile strength, flexural tensile strength, and modulus of elasticity, porosity, density, and water absorption tests were performed to analyze the mechanical and physical properties of the mixtures. One-way Analysis of Variance (ANOVA) was used to identify the influences of RCA on RCC’s mechanical properties. As RCA increased in mixtures, some mechanical properties were observed to decrease, such as modulus of elasticity, but the same was not observed in the splitting tensile strength. All RCCs displayed compressive strength greater than 15.0 MPa at 28 days, splitting tensile strength above 1.9 MPa, flexural tensile strength above 2.9 MPa, and modulus of elasticity above 19.0 GPa. According to Brazilian standards, the RCA added to RCC could be used for base layers.

Roller Compacted Concrete (RCC) is a technology characterized mainly by the use of rollers for compaction. This construction method permits considerable reduction in costs and construction time of dams and roads. It is necessary to study the curing of RCC especially in hot weather because RCC has no slump and has low W/C ratio. Therefore the primary scope of this research is to study the effect of various curing methods (continuous watering, wet burlap, nylon, sprinkling, curing cycles, and curing compound) after 24 hrs from casting on the physical properties of roller compacted concrete. The mix proportion which was used in this investigation, was designed and laboratory tried on the basis of using 250 kg/m³ of Ordinary Portland Cement. This work involves preparing cylindrical specimens with (diameter of 150 mm and height of 300 mm) for measuring the compressive strength, splitting-tensile strength, and static modulus of elasticity. And it also includes prism specimens with (100×100×400 mm) for measuring the modulus of rupture (flexural strength). Results show that the curing of RCC with continuous watering clearly improved the RCC properties. The results also indicate that the RCC specimens without curing (left in air) suffered from permanent loss of strengths ranging between 20 to 25 % when compared with continuous watering at age of 28 days.

Experimental investigation on the properties of the interface between RCC layers subjected to early-age frost damage

Evaluation of roller compacted concrete for its application as high traffic resisting pavements with fatigue analysis