Durability Of High Performance Concrete Research Articles

Effect of Cement Dosing Without Additions (CPA) on High-Performance and Ordinary Concrete Based Glass Powder as Fine Partial Cement Replacement - A Comparative Study

Abstract The main objective of this paper research is a comparative study on the effect of the glass powder (GP) substitute from collected and recycled glass waste, as a fine partial cement replacement on the mechanical performance and durability of high performance concrete (HPC) and ordinary concrete (OC). For this two cement dosing were used of 400 kg/m3 to formulate OC and 450 kg/m3 to formulate HPC, and GP as considered binder like cement and not as fine addition, hence binder represent the sum of cement with GP (L=C+GP) with which will be made our two concretes formulation. Two ratios were used for the Water/Binder (W/B), the first W/B=0.35 for the HPC and the second W/B=0.5 for the OC, this ration is very important to fix the concentration of superplasticizer. A percentage of 10% and 20% substitution of cement CPA without additions noted CEM I 52.5 by the glass powder with fineness of 3600 cm 2/g are used. The evaluation of the compressive strength was followed from 7 to 365 days in order to study the behavior of the GP at different ages affected by the cement dosing and the ratio W/B compared to the reference concrete without GP for the two concretes HPC and OC. At 28 days the strengths of concretes with GP is affected by the replacement of a quantity of cement since the two reference concretes were superior but beyond this age an inverse behavior is noticed such that results obtained at age of 365 days seem to be advantageous in terms of savings in the quantity of cement used by interpreting the compressive strength, and the decrease in quantity of water in the mixtures offers a remarkable difference between the two concretes studied by using 20 % of GP as replacement of cement.

Strength and Durability of High Performance Concrete Using Local Materials

Strength and Durability of High Performance Concrete Using Local Materials

Enhancing Mechanical Behaviour and Durability of High Performance Concrete with Silica Fume, Ground Blast Furnace Slag, and Marble Powder

Abstract This study investigates the impact of waste additives on the behaviour of high-performance concrete and its environmental implications, with a specific focus on resource conservation. The research objectives were realised through the preparation of high-performance concrete specimens incorporating industrial waste materials and marble powder as partial replacements for cement and fine aggregates, respectively. Silica fume and ground blast furnace slag were introduced as substitutes for 8% of the cement’s weight. Powdered marble was volumetrically substituted at levels of 5%, 10%, and 15% of the fine aggregates. The physical and mechanical properties of both fresh and cured concrete specimens were evaluated at different ages, encompassing parameters such as density, compressive strength, impulse velocity, water absorption, and durability. The findings demonstrated that high-performance concrete formulated with silica fume and ground blast furnace slag exhibited superior properties compared to compositions relying exclusively on Portland cement. Furthermore, the inclusion of marble powder as an alternative building material constituent in high-performance concrete resulted in increased efficiency and improved resistance against chemical acid attacks. Significantly, this approach contributes to reduce aggregate demands, environmental preservation, and the production of environmentally sustainable concrete.

Comparative analysis of natural nanosilica versus commercial nanosilica on compressive strength and durability of high-performance concrete

Comparative analysis of natural nanosilica versus commercial nanosilica on compressive strength and durability of high-performance concrete

Study on the preparation of high performance water reducer by nano-micron monomer in the durability of high performance concrete

With the rapid development of economy, the scale of construction industry is gradually expanding, and the construction performance and comprehensive performance of each construction project are developing faster and faster. Compared with the traditional superplasticizer, nano-sized polycarboxylic acid superplasticizer has the advantages of high water reducing rate, small collapse loss and good cement adaptability. China’s polycarboxylic acid high performance water reducer is mainly used in high-speed railway, highway, bridge and other key projects, the market share of commercial concrete is relatively low. In this paper, the research of nano-sized large monomer polycarboxylic acid high performance water reducer in high performance concrete under microscope is studied. The effect of nano-sized large monomer polycarboxylic acid high performance water reducer on durability and compressive strength of high performance concrete is studied.

Effect of fiber synergy on strength & durability of high-performance concrete

The distinct fiber addition to concrete can improve weak performance in tension. Due to its higher performance, fiber hybridization is becoming more and more competitive. In this study, the hardened and durability characteristics of performance-based concrete reinforced with polypropylene, basalt and hooked end steel fibers are investigated. Total 12 mixes are prepared to evaluate the different characteristics of performance-based concrete. The influence of basalt fibers (0.2, 0.25, 0.5, 0.75 & 1%), polypropylene fibers ( 0.025, 0.03, 0.035, 0.05 & 1%), hooked end steel fibers (0.225, 0.475, 0.65, 0.75, 0.80 & 1%) to explore the impact of fiber synergy, various hybrid fibers with maximum volume fraction of 1% were used out of total concrete volume with and without copper slag (20% & 40%) replacement with fine aggregate are investigated on the hardened characteristics including; compressive strength, flexural strength, splitting tensile strength. Moreover, durability properties including; water absorption, electrical Resistivity, for performance-based concrete are also conducted. Out of the 12 mixes considered for this study, PP0.05B0.2S0.75CS40 performs better and exhibit excellent performance in terms of strength and durability.

The Effect of Tire-Rubber Pretreatment on the Physical–Mechanical Properties and Durability of High-Performance Concrete

The Effect of Tire-Rubber Pretreatment on the Physical–Mechanical Properties and Durability of High-Performance Concrete

Analysis of High Performance Concrete Mixed with Nano-Silica in Front of Sulfate Attack.

Nano-silica (NS) is an effective material to improve the strength and durability of high-performance concrete (HPC), but little information is available regarding its role in HPC response to long-term sulfate attack. In this study, six different dosages of NS (0%, 1%, 2%, 3%, 4%, and 5%) as cement partial replacement were mixed into HPC and the casted specimens were soaked in sulfate solution for different periods (0, 100, 200, and 300 days). The mass change, dynamic elastic modulus, compressive and splitting strength, microstructure morphology, and porosity characteristics of HPC specimens were measured by mass tests, mechanical properties tests, scanning electron microscopy (SEM), and nuclear magnetic resonance (NMR) tests. The results showed that the incorporation of NS decreased the mass loss, elevated the compressive and splitting strength, and reduced the porosity formation of HPC in front of sulfate attack. The percentage of 1% NS was among the most effective dosages as, after soaking for 300 days, it decreased the mass loss by 13.5%, elevated the elastic modulus as well as compressive and splitting strength by 50.4%, 31.7%, and 69.8% in comparison of unmodified HPC, respectively. The sulfate attack resistance was delayed in a higher (2-5%) mixed dosage, mainly due to the agglomeration of nano particles, especially after long-term reactions. This study can provide experimental references regarding the performance of HPC mixed with NS in front of sulfate attack.

Mechanical performance and autogenous and drying shrinkage of MgO-based recycled aggregate high-performance concrete

The high strength and durability of high-performance concrete (HPC) may be significantly reduced by shrinkage cracking. The use of reactive magnesium oxide (MgO) can reduce shrinkage of cement-based materials due to its expansive properties. This study intends to analyse the validity of MgO as shrinkage-reducing agent in recycled aggregate HPC. To do so, ten HPC mixes with 0%, 25%, and 100% of both early-age (7-days air curing) and matured (6-month air curing) RA were produced. In half of the mixes, 10% ordinary Portland cement was replaced with MgO. The use of MgO slightly worsened the mechanical behaviour of HPC, especially when combined with large amounts of RA. On the other hand, the expansion of MgO fully offset the autogenous shrinkage of HPC and reduced total shrinkage by around 20–40%. Water storage of RA, and its deferred release over time, produced a more efficient hydration of MgO, which in turn led to a further reduction of autogenous shrinkage. However, the increase of drying shrinkage caused by RA was greater than this decrease of autogenous shrinkage due to MgO, so the higher the RA content of HPC the lower the total shrinkage reduction when adding MgO. Thus, the decrease of total shrinkage caused by MgO was compensated by the shrinkage increase because of RA when adding amounts above 35% early-age RA and 42% matured RA. Therefore, despite the suitability of MgO as shrinkage-reducing agent in recycled aggregate HPC, its effectiveness was reduced with increasing amounts of RA.

Investigating embodied carbon, mechanical properties, and durability of high-performance concrete using ternary and quaternary blends of metakaolin, nano-silica, and fly ash.

Research for alternative binders has become a necessity due to cement's embodied carbon, climate change, and depletion of natural resources. These binders could potentially reduce our reliance on cement as the sole binder for concrete while simultaneously enhancing the functional characteristics of concrete. Theoretically, the use of finer particles in the cement matrix densifies the pore structure of concrete and results in improved properties. To validate this hypothesis, current research was designed to investigate how the value-added benefits of nano-silica (NS) and metakaolin (MK) in fly ash (FA)-blended cement affect the mechanical and durability characteristics of concrete when used asternary and quaternary blends. Additionally, the cost-benefit analysis and environmental impact assessment were conducted. It was observed that the synergy of MK and NS used in FA-blended cement had a greater impact on enhancing the functional characteristics of concrete, while 10% MK as ordinary Portland cement (OPC) replacement and 1% NS as an additive in FA-blended OPC concrete was the optimum combination which achieved 94-MPa compressive strength at the age of 91 days and showed more than 25% increment in the flexural and splitting tensile strengths compared to the control mix (MS00). The ultrasonic pulse velocity and dynamic modulus of elasticity were significantly improved, while a significant reduction in chloride migration of 50% was observed. In terms of environmental impact, MS100 (30% FA and 10% MK) exhibited the least embodied CO2 emissions of 319.89 kgCO2/m3, while the highest eco-strength efficiency of 0.268 MPa/kgCO2·m-3 with respect to 28-day compressive strength was exhibited by MS101. In terms of cost-benefit, MS00 was determined the cheapest, while the addition of MK and NS increased the cost. The lowest cost of producing 1 MPa was exhibited by MS01 with a merely 0.04-$/MPa/m3 reduction compared to MS00.

Methods of assessing the durability of high performance concrete

To ensure concrete durability in reinforced concrete structures is one of the main problems of modern concrete technology. In the State Standard (GOST 31384-2017) we can find the restrictions to concrete composition depending on the class and index of operating media, but there is no information on how they affect the durability, what kind of service life of concrete and reinforced concrete structures they guarantee. This articles shows that the restrictions to concrete composition are necessary but not sufficient to ensure concrete durability especially under harsh conditions of its operation. This is due to the fact that in the national standards the role of the basic concrete strength index, which is the microstructure of hydrated phases of cement stone, is not taken into consideration. The cement gel formed by calcium hydrocilicates and being the densest and strongest component of the structure, determines the concrete durability provided it is stable in specific environmental operating conditions. The proposed methods of assessing the stability of concrete microstructure make it possible to optimize technological parameters of production of reinforced concrete structures of high performance and durability.

Study on SAP with different absorption capacities and its effects on Self Curing HPC

Internal moist curing by Super Absorbent Polymer (SAP) plays an vital role in strength development and durability of High Performance Concrete (HPC). The aim of this study is to examine how the strength reduction happens by adding super absorbent polymer and rectification of strength reduction using micro fillers. The amount of SAP added to the concrete was calculated using the absorption capacity that was obtained as a result of tea bag test. The present study also involves the use of super absorbent polymer in gel and dry state to both mortar and concrete. First strength property was tested in mortar for both gel and dry state. It was found that SAP added in dry state to mortar has no adverse effect on compressive strength and tested. In the present work additional micro filler (silica fume) with different ratios: 0.0%, 10%, 15%, 20% of weight of cement is added to improve the mechanical properties of high strength concrete with SAP. The concrete samples are subjected to ambient curing and mechanical properties (compressive strength and modulus of rupture) were evaluated at different ages, up to 28 days. Durability property such as sorptivity, water absorption and carbonation was conducted on HPC. The effect of internally cured concrete was studied and compared with conventionally cured concrete.

Effect of Mineral Aggregates and Chemical Admixtures as Internal Curing Agents on the Mechanical Properties and Durability of High-Performance Concrete

In the present work, the effect of mineral aggregates (pumice stone and expanded clay aggregates) and chemical admixtures (superplasticizers and shrinkage reducing additives) as an alternative internal curing technique was investigated, to improve the properties of high-performance concrete. In the fresh and hardened state, concretes with partial replacements of Portland cement (CPC30R and OPC40C) by pulverized fly ash in combination with the addition of mineral aggregates and chemical admixtures were studied. The physical, mechanical, and durability properties in terms of slump, density, porosity, compressive strength, and permeability to chloride ions were respectively determined. The microstructural analysis was carried out by scanning electronic microscopy. The results highlight the effect of the addition of expanded clay aggregate on the internal curing of the concrete, which allowed developing the maximum compressive strength at 28 days (61 MPa). Meanwhile, the replacement of fine aggregate by 20% of pumice stone allowed developing the maximum compressive strength (52 MPa) in an OPC-based concrete at 180 days. The effectiveness of internal curing to develop higher strength is attributed to control in the porosity and a high water release at a later age. Finally, the lowest permeability value at 90 days (945 C) was found by the substitutions of fine aggregate by 20% of pumice stone saturated with shrinkage reducing admixture into pores and OPC40C by 15% of pulverized fly ash. It might be due to impeded diffusion of chloride ions into cement paste in the vicinity of pulverized fly ash, where the pozzolanic reaction has occurred. The proposed internal curing technology can be considered a real alternative to achieve the expected performance of a high-performance concrete since a concrete with a compressive strength range from 45 to 67 MPa, density range from 2130 to 2310 kg/m3, and exceptional durability (< 2000 C) was effectively developed.

Synergetic effect of a super-absorbent polymer and a calcium nitrite corrosion inhibitor in high performance concrete durability

In this research, the synergetic effect of a super-absorbent polymer in combination with a calcium nitrite corrosion inhibitor were evaluated as a combined technology to improve concrete durability in High Performance Concrete. For this purpose, Portland cement mortars with a water/cement ratio of 0.4 and a substitution of 9.5% of cement by silica fume were produced. The effect of this technologies was evaluated by measuring the following parameters: autogenous and drying shrinkage, surface electrical resistivity and the non-steady-state chloride migration coefficient. The results indicate that the synergistic effect of SAP + CNI improves autogenous shrinkage and surface electrical resistivity.

Influence of pumice on mechanical properties and durability of high performance concrete

High performance concrete (HPC) which combines Portland cement and other natural and artificial pozzolans mainly aims to extend the service life of concrete structures in harsh environments. Recently, volcanic pumice pozzolan (VPP) has been effectively used to enhance the performance of HPC. VPP is a natural environment friendly material of volcanic origin and it is found abundantly in western parts of the USA. This study explored thirty-seven various concrete mixtures, which includes ordinary Portland cement (OPC) and other binary and ternary mixtures integrating the ultrafine VPP as a major supplementary cementitious material (SCM) along with other cementitious materials namely fly ash, slag, silica fume and metakaolin. The research was conducted to evaluate two performance parameters namely the compressive strength and the durability due to chloride-induced corrosion. Two different non-destructive testing instruments, namely 4-point Wenner Probe and Merlin meter were utilized to investigate the surface resistivity (SR), the bulk resistivity (BR) and the charge passed within a very short time. These are important hardened concrete properties related to the corrosion resistance of reinforced concrete structures. The results indicated that the binary and ternary-based VPP mixtures have remarkably higher compressive strength and very low permeability compared to OPC and other SCM based binary mixtures from early ages to long-term period (up to 91 days). Further, the results showed the compressive strength has a strong correlation with SR and BR over long period. Overall, the ternary VPP based mixtures revealed promising outcomes by means of strength and corrosion resistance and possible implementation in future reinforced concrete bridges.

Studying the effect of low reactivity metakaolin on free and restrained shrinkage of high performance concrete

Producing high performance concrete with a low reactivity pozzolan such as metakaolin is challenging. On the other hand, high performance concretes could be more prone to shrinkage cracking due to their higher cement content. No consensus exists in the literature on how metakaolin affects concrete's shrinkage. In this study, the possibility of making high performance concrete with a low reactivity metakaolin was assessed. Moreover, the effect of using a low reactivity metakaolin on the mechanical properties, durability, and free and restrained shrinkage of high performance concrete was evaluated. The results showed that increase in the percentage of metakaolin replacement led to reduction in the mechanical properties and durability of high performance concrete. The effect of metakaolin on shrinkage of high performance concrete was observed to be dependent on the water to cement ratio. Overall, it is possible to produce high performance concrete with a low reactivity metakaolin (up to 20% replacement level) only at low water to cement ratios.

Strength Development and Durability of High Performance Concrete with Age

Strength Development and Durability of High Performance Concrete with Age

Drying Shrinkage and Suppression Technology of HPC in Extremely Arid Area

Supplementary materials Such As Slag (SG), Fly Ash (FA) and Silica Fume (SF) are necessary for reducing the drying shrinkage of High-performance Concrete (HPC) in arid environments and extremely arid area. This paper investigates the drying shrinkage of HPC with the composites of 10% Silica Fume (SF) and 20% Fly Ash (FA) additions and another HPC incorporated with 10% SF?20% FA and 20% slag (SG), which were exposed to the conditions of 30% Relative Humidity (RH) and 50% RH. The inhibitive mechanism of Aluminate Expansion Agent (AEA) on the drying shrinkage of HPC reveals that the dry shrinkage can be inhibited by the expansion agent as long as the high density of concrete structure and the internal “surplus water” can be ensured. Furthermore, the additions of the composites of SF, FA and SG, super-plasticizer, high modulus fiber (PF) and AEA, can reduce the drying shrinkage and improve the moisture sensitivity of shrinkage of the concrete. The drying shrinkage rate of HPC in extremely harsh environment decreased to about 300 × 10−6 and no shrinkage cracks appeared on the surface of the HPC incorporated with SF, FA and SG. The perfect combination of high volume stability and high durability of HPC was realized.

Durability performance of high-performance concrete made with recycled aggregates, fly ash and densified silica fume

This study intends to analyse the effects of the incorporation of recycled aggregates (RA) and densified silica fume (SF) on the durability of high performance concrete (HPC). Considering that the mortar adhered to the RA strongly influences the behaviour of the concrete made with it, the source of these aggregates was restricted to precast mixes with target compressive strengths of 75 MPa and subjected to a primary plus a secondary crushing process. With regard to SF, a certified commercial product was used, which was incorporated in the concrete as an additional material to cement. The experimental campaign included the production of 12 types of concrete, which were evaluated by means of water absorption by immersion, water absorption by capillarity, resistance to carbonation, resistance to chloride penetration and permeability to oxygen tests. The results show that it is possible to produce HPC with significant quantities of fine and coarse recycled aggregates (FRA and CRA) as replacement of traditional fine and coarse natural aggregates (FNA and CNA). Ultimately, considering the properties analysed, it seems possible to produce HPC without incorporating natural aggregates (NA). The incorporation of densified silica fume contributed to an increase of concrete's performance through the use of a mixing process developed by the authors that minimized the previously endured dispersion difficulties associated with this product.

Effect of Pharmaceutical Wastes Usage as Partial Replacement of Cement on the Durability of High-Performance Concrete

This paper reports an experimental study of the influence of ash produced from incinerated hospital wastes used as partial substitute for Portland cement (PC) on the mechanical properties and durability of high performance concretes. The analysis of the experimental results on concrete at 10% content of ash resulting from incineration of pharmaceutical wastes with a fineness modulus of 8000 cm2/g, in a chloride environment, showed that it contributes positively to the perfection of its mechanical characteristics, its durability with respect to migration of chloride ions and oxygen permeability. On the basis of the experiments performed, it can be concluded that the ash is suitable for formulation of high performance concretes (HPC) and their properties are significantly better compared to the reference concrete (RC). This paper points out the directions for the proper uses of ash of pharmaceutical wastes in concrete.