Compacted Concrete Research Articles

Two-lift concrete pavement with advanced fibre reinforced concrete as the top lift and roller compacted concrete as the bottom lift

Roller Compacted Concrete (RCC), developed for pavements and dams due to its low cement content, is constrained by limited fatigue resistance, making it suitable only for low-traffic pavements. This study aims to develop a high-fatigue-resistant Two-lift Concrete Pavement (TLCP) incorporating RCC, with three primary objectives: (i) constructing TLCP with a two-thirds RCC bottom layer and a one-third ultra-high-performance fiber-reinforced concrete (UHPFRC) or engineered cementitious composites (ECC) top layer, (ii) conducting fatigue testing on 225 specimens, and (iii) analyzing fatigue data using statistical methods to determine the best approach. Results showed that TLCP specimens had higher compressive and flexural strengths than RCC, though lower than UHPFRC or ECC. A graphical method was found most accurate for predicting fatigue life. TLCP with UHPFRC achieved 3.85–7.5 times greater fatigue life, while TLCP with ECC showed 2.63–5.96 times higher fatigue life than RCC, with ECC offering significant cost savings.

Two-Phase Flow Modelling Based on Roughness Surface Effect of Roller Compacted Concrete

One of the most important considerations that are interest to researchers on the stepped spillway in hydraulic structure is the location of the point at which the flow begins to transform into two phase-flow and the development of boundary layers. In this study, an unconventional rough surface was used (RCC materials), which has completely different properties from what is used in previous laboratory studies, which uses smooth surfaces in reality to represent the actual roughness of the surface. Benchmark mixes are evaluated as a reference standard concrete to determine the optimal combination proportions for RCC according to The U.S. Army Corps of Engineers Standard. A laboratory study of different models enhanced by a mathematical model CFD with VOF technics to described the two- phase interaction to investigate the location of the inception point and compare the results with the proposed equations assumed by different researchers in this topic. The results obtained from the study showed a clear effect of surface roughness on the location of the inception point and the formation of the boundary layer for laboratory models. It’s clearly found that the two-phase flow starts with closer locations than it is for conventional models and the ratios vary (10 % - 20 %) according to the discharge values (where the effect of surface roughness is evident in the low discharges compared to the high discharges in which the boundary Lear effect begins to fade.

Analyzing Lab and Field Compaction Methods for designing Roller Compacted Concrete Pavements (RCCP) with Different Curing Processes

Analyzing Lab and Field Compaction Methods for designing Roller Compacted Concrete Pavements (RCCP) with Different Curing Processes

Design of Two-Layer Roller Compacted Concrete with Joints by KENSLAB

Roller compacted concrete (RCC) is a type of rigid pavement that is designed in a similar way to conventional concrete pavements reflecting its mode of failure. The thickness design of RCC pavements is based on keeping the flexural stresses and fatigue damage in the pavement caused by wheel loads within allowable limits. As in all jointed concrete pavements, there is a greater effect from loads placed along edges and less at interior locations in the pavement. Joints in RCC pavement are clearly critical areas and form weak points. RCC is typically constructed with saw-cut joints to prevent random cracking, improve the appearance of the pavement surface, and maintain the highest possible load transfer across the joints. This paper presents an approach to designing the thickness of a two-layer RCC with induced cracks (i.e., joints) based on load transfer stiffness and fatigue damage, using the KENSLAB program to obtain pavement life, predict joint deterioration, and pavement damage.

Analytical Overview of the Methods of Controlling the Parameters of Vibratory Compaction of the Concrete Mixes

Introduction. A historical (retrospective) overview of the evolution and application of the methods of concrete mixture compaction by vibration, as well as an overview of the breakthrough scientific+ advancements in the studied field have been presented. The use of the dry concrete mixes that reduce cement consumption, accelerate the strength gain of concrete, reduce the shrinkage strain and heat emission and increase the strength and durability of products has been proposed. The theoretical and practical issues of vibratory compaction of the concrete mixes, the research on the effect reached by the various vibration modes of the vibrating tables, the issues of choosing an efficient mode of vibration impact during compacting the concrete mixes and optimisation of their parameters have been studied. The vibrating table design, the installation layout of the vibrator’s eccentric weights to obtain a given value of the exciting force and the layout of a vibration module with the directed vibrations have been studied in detail. The criteria of duration of the concrete mixture compaction have been defined, changes of the impact parameters during compacting the concrete mixes have been characterised and technical specifications of the vibrating tables have been defined. In the article considerable attention has been paid to the main parameters of the vibrocompacting machines: frequency, amplitude and acceleration of the working member. Most often, the parameter of intensity is used to assess the efficiency of the vibration impact received by the mixture during the compaction process.Materials and Methods. A mixture that turns into concrete after compaction, setting and hardening was selected for the research. The various methods and parameters of concrete mixture compaction to obtain the high-quality concrete were studied. The impact of the various vibration modes on the process of compaction of concrete mixes was investigated, the criteria for the efficient selection and optimisation of the vibration impact parameters were revealed. The paper presents the criteria for assessing duration of the concrete mixture compaction and describes the changes in the parameters during compaction of the concrete mixes. The technical specifications of the vibrating tables of different types and sizes were also presented. The choice of the vibration compaction mode for the concrete mixture is a complicated task, which includes many parameters.Results. Upon the research, the data on the process of concrete mixture compaction under the impact of vibration forces has been obtained. The process results in the destruction of the structural bonds and weakening the bonds between the particles, which leads to the emergence of a variable stress-strain condition. It has also been found that under such settings, the mineral particles get transferred and a denser packing is formed.Discussion and Conclusion. The resulting denser packing of the concrete mixture particles ensures the undoubted economic advantage due to reduced consumption of a binder without loss of the strength properties of concrete.

Experimental investigation on the frost resistance of RCC layers with various interface treatments

This research investigates the influence of various interface treatment methods on the frost resistance performance of Roller Compacted Concrete (RCC) layers. Freeze-thaw cycle tests were conducted on RCC with interfaces treated using cement mortar, expansion agent mortar, and nano-SiO2 mortar. The study evaluated shear failure modes, shear strength, crack expansion, pore structure, and liquid uptake of the RCC interface after freeze-thaw cycles under different treatment methods. Results reveal that expansion agent mortar and nano-SiO2 mortar improve the shear strength of RCC after freeze-thaw cycles more effectively than cement mortar. The freeze-thaw cycles increase the width and expansion rate of cracks at the RCC interface during the shear process, while mortar treatments help delay crack development. Additionally, the pore volume at the RCC interface gradually increases, and the uniformity of pore distribution decreases under freeze-thaw cycles. During liquid uptake, mortar treatments slow down the upward migration of liquids by improving the pore structure at the interface. The liquid uptake of RCC exhibits a distinct linear relationship with its shear strength and pore structure. As liquid uptake time increases, water first fills larger pores before gradually entering smaller ones. Freeze-thaw cycles cause an increase in pore volume and enlargement, which leads to greater liquid uptake. Based on the damage mechanism of the RCC interface under freeze-thaw conditions, a model of shear strength degradation due to freeze-thaw cycles was established, aligning well with experimental results. Mechanism analysis indicates that nano-SiO2 and expansion agents enhance frost resistance by filling interface pores and cracks through reactions with certain compounds, thereby improving the microstructure.

Improved probabilistic design method to quantify the fracture properties of roller compacted concrete

In this paper, the material parameters pertaining to fracture properties of Roller Compacted Concrete (RCC) were evaluated using the boundary element method (BEM). The fictitious crack growth length Δafic is determined by the relative size (T-a0)/di, while the individualized values of material parameters (KIC&ft) of RCC for different water-to-cement ratios were obtained. In this study, the three-parameter Weibull fracture statistical model was proposed for the first time to analyze the discreteness of these individualized values of material parameters (KIC&ft) of RCC. The statistical analysis minimum value of material parameters (KIC&ft) of each group is obtained. The failure curves of each group of RCC were predicted from the three-parameter Weibull fracture statistical model, and the simple calculation model for material parameters (KIC&ft) was validated. Further, a two-point design method was proposed for RCC material parameters (KIC&ft) with varying strengths and water-to-cement ratios.

Numerical analysis and experimental research on the vibration performance of concrete vibration table in PC components

Abstract Vibration table is the key equipment to realize high efficiency and high quality forming and compacting of concrete in prefabricated component (PC) production line, and its performance directly affects the shape quality and compressive strength of PC components. However, the operating parameters of the vibration table are difficult to match the rheology of the concrete during the construction process, which directly leads to a low molding efficiency or unqualified shape quality in the case of slab-type components. Therefore, it is crucial to accurately describe the concrete flow behavior during vibration to improve the construction performance and compaction effect. In this work, the coupled theory of computational fluid dynamics and discrete element is used to study the concrete vibration and compacting characteristics, and the influence of process parameters on vibration performance is analyzed in order to realize the adjustment and optimization of key parameters. First, the concrete solid-liquid two-phase model parameters are calibrated by V-shaped funnel experiments and slump experiments. Then, based on the simulation results, the homogeneity and compactness of concrete are discussed using the segmented sieving method and the slicing method, and the indexes for evaluating the working performance of the vibration table are proposed. Finally, the relationship between vibration frequency (20–30 Hz), vibration amplitude (3–4 mm), and vibration time (15–35 s) and concrete vibration compaction characteristics is investigated to provide a theoretical basis for improving the molding efficiency and mold quality of PC components.

Evaluation and optimization of red pine needle-reinforced roller-compacted concrete by bioinspired algorithms

This paper discusses the improvement of roller compacted concrete by the addition of red pine needle (PN) fibers optimized by bioinspired techniques. The purpose was to determine a perfect set of mechanical characteristics, such as flexural, compressive, and splitting tensile strengths, by determining proper correlations between the water-cement ratio, superplasticizer, and fiber volume. Based on the data obtained with the help of experiments, it was shown that optimizing the PN fibers added to RCC with nature-inspired algorithms (particle swarm optimization, genetic algorithms, simulated annealing and artificial neural networks) yields positive results in terms of improving a number of characteristics, including flexural strength, fracture toughness, and durability. In addition, adopting PN fibers has certain environmental benefits. All methods under analysis showed good results, with the artificial neural network (ANN) being superior in terms of predicting the parameters of RCC. The discussed research confirms the effectiveness of such optimization methods for determining the best proportions for RCC using PN fibers. At the same time, future studies could further develop sustainable and mechanically strong RCC formulations.

Sustainable Concreting: Optimization Modelling of the Strength Properties of Bio-Self Compacting Concrete Incorporating Sporosarcina Pasteurii, Calcined Clay and Limestone Powder

Sustainable concreting is prerequisite for infrastructural development in developing countries so as to meet up with the sustainable development goal of adequate mass housing and other critical infrastructure. Thus, research is ever ongoing aimed at developing cheaper and more durable concrete via the incorporation of bio-based by-products in concrete to improve its properties, as well as optimizing the quantities of these secondary materials for maximum and optimal concrete production. One such revolutionary concrete that is yet to find full application in the developing world is self-compacting concrete, because of the cost and attendant environmental effects. There is thus a need to arrive at optimal materials quantities that can maximize concrete properties without recourse to many trial and error experimentations that are both time and resources consuming. The application of modelling tools in concrete technology aids in the optimization of concrete constituents for optimal self-compacting concrete performance. This research uses optimization techniques to optimize the bacteria dosage as well as model the Compressive and Tensile strength properties of a calcined clay and Limestone powder blended ternary self-compacting concrete using sporosarcina pasteurii as Microbial induced calcite precipitation agent and calcium lactate as nutrient source. The Bacteria was incorporated into the concrete at a bacterial content of 1.5x108cfu/ml, 1.2x10 cfu/ml and 2.4x109cfu/ml corresponding to the McFarland turbidity scale of 0.5, 4 and 8 while the nutrient (calcium lactate) content was 0.5, 1.0 and 2.0% by weight of cement for each bacterial content. The Compressive strength and tensile strengths at 28 days were determined and the results used for both the model development, strength optimization and model validation, with the strengths as the dependent variable (y) and the bacterial content corresponding to a McFarland scale of and calcium lactate content as the independent variables, X1 and X2 respectively. The results show an improvement in the compressive strength from 32N/mm2 to 45.2N/mm2 at the optimal bacterial and nutrient content of 1.2x10 cfu/ml and 0.5% respectively, and tensile strength from 4.01N/mm2 to 5.0N/mm2. Also, the non-linear regression models proved adequate for optimizing the bacterial content for optimal self-compacting concrete performance. Journal of Engineering Science 15(1), 2024, 11-19

Effect of Production and Curing Methods on the Properties of Roller-Compacted Concrete: A Review

Roller Compacted Concrete (RCC) exhibits many characteristics of both asphalt and rigid pavements, but their use is restricted. Many reasons led to this decision, including the fact that RCC is a type of concrete mixture that requires a specific consistency. It should be firm enough to be compacted by a roller compactor but also have enough moisture to ensure even distribution. The lab-field performance difference of RCC is another reason for decreasing its use. The laboratory RCC mixes are prepared using the modified Proctor compaction method. Subsequently, specimens are fabricated utilizing a vibratory hammer (VH) to evaluate their strength properties. Nevertheless, in the construction industry, pavement is built utilizing static, pneumatic, and vibratory rollers. Consequently, quality control is carried out by acquiring pavement samples and comparing them to laboratory samples. Each of these procedures employs different processes and energies, resulting in variations in field and laboratory behavior. In this investigation, some studies will be discussed about the RCC behavior under field and lab conditions using various design methods, such as the vibrating table (VH), vibratory table (VT), gyratory compactor (GC), and modified proctor (MP). These studies showed a difference in RCC mechanical and macroscale properties between laboratory compaction methods. For instance, VH specimens led to a higher evaluation, while GY specimens produced a less favorable estimation of the hardened properties observed in the field. While the MP and VT compacted specimens had a comparable structural arrangement to the field, they exhibited notable differences in terms of porosity and strength. Other studies revealed the essence of the curing stage in terms of RCC mechanical properties and indicated that some curing processes, like compound curing, may improve RCC performance.

Temperature Control and Crack Prevention of High RCC Dam in Cold and Drought Area

A development process is introduced for a computation program to calculate the temperature and stress field of mass concrete based on the ANSYS® platform. The temperature control scheme of a high roller compacted concrete (RCC) dam in northern Xinjiang is optimized by using the simulation program. It is suggested that the concrete pouring temperature of the dam should not exceed 16°C and that water-pipe cooling should be adopted. The dam should be permanently heat preserved by 10 cm thick extruded polystyrene (XPS) extruded panels, and the top surface of the overwintering layer should be covered with an at least 14 cm thick thermal insulation quilt. During construction, the warehouse surface should be temporarily insulated with a 2 cm thick thermal insulation quilt. The causes of cracks in a particular dam section are simulated and analysed, and it is concluded that the cracks are mainly caused by the lack of thermal insulation of the warehouse surface during cold spells.

Performance Analysis Relevant to Primary Design Parameters of Pervious Concrete: A Critical Review

Pervious concrete (PC) is a structural element with environmental benefits. The industrial application is highly limited by restrictions in predicting performance owing to high uncertainties and issues in mass-producing with uniform characteristics. Primary performance indicators of PC are compressive strength, porosity, and permeability, where the porosity distribution and pore characteristics are crucial in its mechanical properties. Although compaction can improve uniformity in the properties of concrete, it is properly employed in PCs to ensure connectivity between pores and thereby enhance permeability. The compactability of fresh concrete predominantly depends on binder thickness dictated by aggregate-to-binder (A/B) ratio, water-to-binder (W/B) ratio, aggregate size, shape distribution of aggregates, and interfacial transition zone. In addition, the method of compaction, the compaction energy, and the distribution of compaction energy in the concrete matrix affect the above. The concrete compaction methods and their effectiveness vary between laboratory studies and field-scale installations. This state-of-the-art critical review of literature reviews the performance parameters of PC, compaction types and methods, compactability of PC, and models currently employed to optimize the mix design. It also highlights the potential trends for future studies to assist optimization of compaction in PC. The authors believe that this comprehensive review would assist professionals in developing a standard code of practice for using PC concrete.

Assessing Roller Compacted Concrete using GGBS as Partial Cement Replacing Material for Application in Low Traffic Volume Road

This paper reports most optimized mix derived from the roller compacted concrete (RCC) using ground granulated blast furnace slag (GGBS) as the partial cement replacing materials in the context of possible utilization of RCC in the construction of rigid pavements in the rural part of the country, especially subjected to low vehicular traffic volume. In the current study, various RCC mix compositions were developed by substituting ground granulated blast furnace slag (GGBS) for ordinary Portland cement (OPC) in varied percentages (0%, 20%, 40%, and 50%) and assessed for mechanical (strength) properties. All the three GGBS blended mix compositions are found to give early age compressive strength more than 20 MPa and 28 days compressive strength more than 30 MPa. Further, they are found to have split tensile strength in the range of 2.8-4.1 MPa. Moreover, they are found to yield the flexural strength more than 3.8 MPa. All the three mixes are found to comply with the requirements of compressive strength, splitting tensile strength and the flexural strengths as prescribed by Indian Roads Congress Specification and American Concrete Institute Standards for possible utilization in the construction of rigid pavements in the rural parts of the developing country like India. Further, the strength values of the GGBS blended mixes increases from 20% to 40% and decreases thereafter, at the higher GGBS contents such as 50%. In view of this, the RCC mix composition with 40% GGBS contents can be regarded as the most optimal mix to be used in the construction of rigid pavements in rural part of the country.

Eco-Friendly Roller Compacted Concrete: A Review

Sustainable evolution is vital to address miscellaneous issues, and experts are currently exploring the possibilities of Eco-Friendly concrete (Green concrete). This type of concrete involves using environmentally and economically viable substances that can act as entire or partial replacements for conventional materials. By doing so, it can assist in reducing the consumption of natural resources and energy, as well as minimize pollution. For example, several researchers have performed on incorporating sustainable approaches in roller compacted concrete RCC by replacing certain substances with eco-friendly alternatives. That is a favorable step toward devising more sustainable construction practices. Therefore, this study resorted to reapplying recycled plastic garbage (sustainable plastic) to construct environmentally eco-friendly concrete (green concrete). First, examine the possibility of using plastic as a partial substitute for fine-aggregates in RCC mixtures. Second, examination of the possibility of using plastic as a partial substitute for coarse-aggregates in RCC mixtures to enhance the performance of RCC. In early periods, a suitable RCC mix was designed in the lab to test the concrete strength, freezing-thawing, permeability, durability, erosion, and porosity of set concrete. The findings confirmed that RCC can maintain the same properties as traditional concrete using the known mixtures. Trial tests were designed and organized to evaluate the quality of pouring and compaction operations, suitable mix composition, and void specimens to accomplish testing on the constructed RCC. It has shown that RCC with prime ingredients and proper ratios can be performed with similar strength and durability as conventional concrete. However, RCC differs from ordinary concrete pavements. This technology provides a favorable economical alternative for many branches of civil engineering installations.

Dynamic response of Akcakoca RCC Dam including galleries

Dams are structures that demand a significant amount of concrete, making them costly constructions. Hence, various alternative methods are employed for dam construction, one of which is the use of Roller Compacted Concrete (RCC). This is a case study, which focuses on examining the behavior of RCC dams with and without galleries under seismic excitations, considering the Akçakoca RCC dam in Düzce Province. The seismic ground motion data from the 1999 Düzce earthquake were utilized. The impact of galleries inside the concrete dams was investigated through stress and displacement, considering both empty and full reservoir conditions. The Eulerian-Lagrangian coupled (CEL) approach was employed for two-dimensional fluid finite elements. This study revealed that reservoir water and galleries have a notable influence on the behavior of dams under seismic forces. In cases with reservoirs and galleries, stress and displacement values increased, and critical changes in stresses were observed around gallery areas. Therefore, careful design considerations are essential for dams with galleries under significant seismic forces.

Studying the effect of the ratio of water to binder and sand to aggregate on the hardness of concrete mixtures and compressive strength of roller-compacted concrete by experimental method

In roller-compacted concrete technology, withthe use of low water and cement content, the concrete mixture after kneading has high hardness and compaction equipment must be used to compact and shape the product.Therefore, the content of mixing water, binder, and aggregate are considered decisive factors, greatly affecting the properties of roller compacted concrete in both the fresh state and the hardened state.The paper uses the mathematical method of two-factor rotatable central compositional planning to simulate the effect of volumetric ratios of water-binder (VN/VCKD) and sand-aggregate (VC/VCL) on the objective functions of the test. The selected objective functions are the hardness of the concrete mixture and the compressive strength of the roller-compacted concrete at the age of 28 days.From the obtained objective functions, it is shown that both control variables VN/VCKDand VC/VCLhave a significant influence on the valuesof the experimental model. When the VN/VCKDratio increases, the water content contributes to increasing the plasticityand reducing the hardness of the concrete mixture. At the same time, excess water exists in the concrete mass in the form of air bubbles,pores,and magnetism. That reduces the compressive strength of the product. Furthermore, the VC/VCLratio of the aggregate that is too small or too large tends to cause the compressive strength of the concrete to decrease.

Experimental study of light transmitting concrete with ultra-high content of polymethyl methacrylate

Light Transmitting Concrete (LTC) is an innovative material for crafting unique and sustainable architectural and civil structures. Previous studies primarily utilized optical fibers with diameters below 1.5 mm, which did not exceed 10 % of the volumetric content in concrete. This study aims to develop LTC with ultra-high light transmission capabilities while preserving its mechanical strength. An important innovation is the use of polymethyl methacrylate (PMMA) with larger diameters than normal optical fibers. Specifically, PMMA fibers of 2.0 mm diameter and PMMA tubes of 10–20 mm diameter were employed to increase the spacing between these materials when arranged in an ultra-high volumetric content within the concrete, facilitating easier compaction of the fresh concrete. Experiments of the material's mechanical properties, microstructure, and optical performance were conducted. The findings suggest that although the increased PMMA content might reduce the concrete’s mechanical strength due to a smaller effective cross-sectional area, the LTC still achieves compressive strength exceeding 40 MPa. This underscores the viability of LTC with a substantially higher content of light transmitting functional materials compared to previous studies, while still maintaining a mechanical strength greater than normal concrete. The light transmission efficiency of LTC is nearly directly proportional to its PMMA content, and able to reach up to 30 % of the light source's intensity. Additionally, LTC with PMMA fibers provides uniform light distribution across its surface because of scattering, while LTC with larger-diameter PMMA tubes focuses light around the core areas due to direct lighting.

Assessment of Special Rubberized Concrete Types Utilizing Portable Non-Destructive Tests

Concrete is the second most common material demanded over the world. Recently, a trending issue is the vast tracking in constructing infrastructure to ensure traffic movement and life quality. Concrete types such as self and rolled compacted concrete offer magical solutions ensuring vast infrastructure and life quality. However, these structures must be assessed using non-destructive testing methods to observe the difference between the concrete types. Several studies have used recycled waste, specifically the crumb rubber extracted from old tires, as a potential replacement for natural aggregate in concrete manufacturing. However, limited research has been devoted to nondestructive testing of produced concrete to further evaluate existing concrete elements containing crumb rubber. This study investigates the self and rolled compacted concrete in comparison with normal ones, in addition to using chopped rubber as recycled materials. This study examines the concrete manufactured destructively by evaluating its compressive, tensile, and flexural strength, in addition to impact resistance, and correlates those results with the non-destructive such as Schmit hammer and Ultrasonic Pulse (UPV) for extended utilization of the concrete produced and data publication. The results showed unique performance and a high potential for data contribution to the extensive utilization of self-compacted rubberized concrete and rolled compacted concrete.

Effect of Different Steel Fibres on Strength Parameters of Self Compaction Concrete

Effect of Different Steel Fibres on Strength Parameters of Self Compaction Concrete