scholarly journals Performance Assessment of Waste Fiber-Reinforced Mortar

2012 ◽  
Vol 730-732 ◽  
pp. 617-622 ◽  
Author(s):  
Cristiana Gonilho-Pereira ◽  
Paulina Faria ◽  
Raul Fangueiro ◽  
Ana Martins ◽  
Pedro Vinagre ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Dynamic Modulus ◽  
Hydrated Lime ◽  
Capillary Absorption ◽  
Fibrous Materials ◽  
Fiber Reinforced ◽  
Through Flow ◽  
Flow Table ◽  
Lime Mortars ◽  
Binder Type

In this paper an experimental work is presented which main objective is the evaluation of the influence of different percentages of waste fibrous materials usage on the performance of fiber-reinforced mortars. Moreover, the influence of binder type is evaluated. Therefore mortars were produced with two different binders – cement and powder hydrated lime. Mortars performance evaluation was carried out through flow table and plunger penetration consistency, dynamic modulus of elasticity, flexural and compressive strength, capillary absorption, drying index and adherence tests. The benefits revealed in some characteristics of both mortars by the use of waste fibers are discussed.

scholarly journals MECHANICAL PERFORMANCE OF LIME-CEMENT MORTAR FOR STRAW-BALE CONSTRUCTION

2014 ◽  
Vol 9 (3) ◽  
pp. 100-115
Author(s):  
Colin MacDougall ◽  
Stephen Vardy
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Mechanical Performance ◽  
Failure Strain ◽  
Cement Mortar ◽  
Hydrated Lime ◽  
Empirical Equations ◽  
Curing Time ◽  
Lime Mortars ◽  
Straw Bale

Experimental data describing the mechanical performance of Portland cement- hydrated lime mortars used for straw bale construction is presented. Straw bale construction uses stacked straw bales plastered on each side to form load-bearing elements. Mortars used have slumps of approximately 50 mm, compared to slumps up to 279 mm for conventional masonry mortars. Cylinder and cube tests of a range of typical straw bale mortar mixes were carried out. The mortars had compressive strengths ranging between 0.3 MPa and 13 MPa. Empirical equations describing the relationships between compressive strength and curing time, w/cm ratio, proportions of lime, cement and sand, and modulus of elasticity are presented. The data show that cement-lime mortars for straw bale construction will have a higher modulus of elasticity and lower failure strain than a conventional mortar of equivalent compressive strength. The Modulus of Elasticity is on average 818 times the compressive strength of a straw bale mortar, compared to 100 to 200 times as reported in the literature for conventional mortar. The average failure strain for straw bale mortar is 0.00253 compared to 0.0087 to 0.0270 reported in the literature for conventional mortar.

scholarly journals Early-age compressive strength and dynamic modulus of FRC based on ultrasonic pulse velocity

2021 ◽  
Vol 71 (343) ◽  
pp. e257
Author(s):  
D. Castillo ◽  
S. Hedjazi
Keyword(s):  
Compressive Strength ◽  
Dynamic Modulus ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Fiber Reinforced Concrete ◽  
Experimental Program ◽  
Early Age ◽  
Fiber Reinforced ◽  
Different Types

Due to the increasing use of rapid construction methods and the challenges of maintaining construction schedules, a growing demand exists for procedures that can assure quality of work without sacrificing the pace of construction. The quality control of construction materials specifically, the mechanical properties of concrete are among the most important concerns in today’s construction industry. In the present study, the correlation between fiber-reinforced concrete’s compressive strength and dynamic modulus to its ultrasonic pulse velocity is investigated at early ages up to 7 days after mixing. An experimental program involving 189 FRC specimens were designed containing different types of structural fibers, fiber volume fractions, and water-to-cement ratios. Mathematical equations were developed to predict the early-age compressive strength and dynamic modulus of four different types of fiber-reinforced concrete based on ultrasonic pulse velocity. The predicted compressive strength and dynamic modulus from the proposed equations showed good agreement with the measured ones.

Effect of combined drink cans and steel fibers on the impact resistance and mechanical properties of concrete

2020 ◽  
Vol 14 (2) ◽  
pp. 6734-6742
Author(s):  
A. Syamsir ◽  
S. M. Mubin ◽  
N. M. Nor ◽  
V. Anggraini ◽  
S. Nagappan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Reinforced Concrete ◽  
Impact Resistance ◽  
Fiber Reinforced Concrete ◽  
Steel Fibers ◽  
Fiber Reinforced ◽  
Indirect Tensile ◽  
The Impact

This study investigated the combine effect of 0.2 % drink cans and steel fibers with volume fractions of 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the mechanical properties and impact resistance of concrete. Hooked-end steel fiber with 30 mm and 0.75 mm length and diameter, respectively was selected for this study.  The drinks cans fiber were twisted manually in order to increase friction between fiber and concrete. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the strength performance of concrete, especially the compressive strength, flexural strength and indirect tensile strength. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the compressive strength, flexural strength and indirect tensile strength by 2.3, 7, and 2 times as compare to batch 1, respectively. Moreover, the impact resistance of fiber reinforced concrete has increase by 7 times as compared to non-fiber concretes. Moreover, the impact resistance of fiber reinforced concrete consistently gave better results as compared to non-fiber concretes. The fiber reinforced concrete turned more ductile as the dosage of fibers was increased and ductility started to decrease slightly after optimum fiber dosage was reached. It was found that concrete with combination of 2% steel and 0.2% drink cans fibers showed the highest compressive, split tensile, flexural as well as impact strength.    

scholarly journals Towards Sustainable Concrete Composites through Waste Valorisation of Plastic Food Trays as Low-Cost Fibrous Materials

2021 ◽  
Vol 13 (4) ◽  
pp. 2073 ◽  
Author(s):  
Hossein Mohammadhosseini ◽  
Rayed Alyousef ◽  
Mahmood Md. Tahir
Keyword(s):  
Compressive Strength ◽  
Low Cost ◽  
Impact Resistance ◽  
Food Tray ◽  
World Population ◽  
Fibrous Materials ◽  
Palm Oil Fuel Ash ◽  
Waste Plastic ◽  
Compressive Strength Of Concrete ◽  
The Impact

Recycling of waste plastics is an essential phase towards cleaner production and circular economy. Plastics in different forms, which are non-biodegradable polymers, have become an indispensable ingredient of human life. The rapid growth of the world population has led to increased demand for commodity plastics such as food packaging. Therefore, to avert environment pollution with plastic wastes, sufficient management to recycle this waste is vital. In this study, experimental investigations and statistical analysis were conducted to assess the feasibility of polypropylene type of waste plastic food tray (WPFT) as fibrous materials on the mechanical and impact resistance of concrete composites. The WPFT fibres with a length of 20 mm were used at dosages of 0–1% in two groups of concrete with 100% ordinary Portland cement (OPC) and 30% palm oil fuel ash (POFA) as partial cement replacement. The results revealed that WPFT fibres had an adverse effect on the workability and compressive strength of concrete mixes. Despite a slight reduction in compressive strength of concrete mixtures, tensile and flexural strengths significantly enhanced up to 25% with the addition of WPFT fibres. The impact resistance and energy absorption values of concrete specimens reinforced with 1% WPFT fibres were found to be about 7.5 times higher than those of plain concrete mix. The utilisation of waste plastic food trays in the production of concrete makes it low-cost and aids in decreasing waste discarding harms. The development of new construction materials using WPFT is significant to the environment and construction industry.

scholarly journals Compressive Strength of Modified FRP Hybrid Bars

Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1898
Author(s):  
Marek Urbański
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Basalt Fiber ◽  
Test Method ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Free Length ◽  
Compression Properties ◽  
Reinforced Polymer ◽  
Frp Bars

A new type of HFRP hybrid bars (hybrid fiber reinforced polymer) was introduced to increase the rigidity of FRP reinforcement, which was a basic drawback of the FRP bars used so far. Compared to the BFRP (basalt fiber reinforced polymer) bars, modification has been introduced in HFRP bars consisting of swapping basalt fibers with carbon fibers. One of the most important mechanical properties of FRP bars is compressive strength, which determines the scope of reinforcement in compressed reinforced concrete elements (e.g., column). The compression properties of FRP bars are currently ignored in the standards (ACI, CSA). The article presents compression properties for HFRP bars based on the developed compression test method. Thirty HFRP bars were tested for comparison with previously tested BFRP bars. All bars had a nominal diameter of 8 mm and their nonanchored (free) length varied from 50 to 220 mm. Test results showed that the ultimate compressive strength of nonbuckled HFRP bars as a result of axial compression is about 46% of the ultimate strength. In addition, the modulus of elasticity under compression does not change significantly compared to the modulus of elasticity under tension. A linear correlation of buckling load strength was proposed depending on the free length of HFRP bars.

scholarly journals Predicting the behavior of reinforced concrete columns confined by fiber reinforced polymers using data mining techniques

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Sahar Y. Ghanem ◽  
Heba Elgazzar
Keyword(s):  
Compressive Strength ◽  
Reinforced Concrete ◽  
Compressive Stress ◽  
Compressive Strain ◽  
Concrete Columns ◽  
Steel Reinforcement ◽  
Fiber Reinforced Polymers ◽  
Stress And Strain ◽  
Fiber Reinforced ◽  
The Impact

AbstractFiber Reinforced Polymer (FRP) usage to wrap reinforced concrete (RC) structures has become a popular technology. Most studies about RC columns wrapped with FRP in literature ignored the internal steel reinforcement. This paper aims to develop a model for the axial compressive strength and axial strain for FRP confined concrete columns with internal steel reinforcement. The impact of FRP, Transverse, and longitudinal reinforcement is studied. Two non-destructive analysis methods are explored: Artificial Neural Networks (ANNs) and Regression Analysis (RA). The database used in the analysis contains the experimental results of sixty-four concrete columns under the compressive concentric load available in the literature. The results show that both models can predict the column's compressive stress and strain reasonably with low error and high accuracy. FRP has the highest effect on the confined compressive stress and strain compared to other materials. While the longitudinal steel actively contributes to the compressive strength, and the transverse steel actively contributes to the compressive strain.

scholarly journals Diagnosis and Assessment of Deep Pile Cap Foundation of a Tall Building Affected by Internal Expansion Reactions

Buildings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 104
Author(s):  
Fernando A. N. Silva ◽  
João M. P. Q. Delgado ◽  
António C. Azevedo ◽  
Tahlaiti Mahfoud ◽  
Abdelhafid Khelidj ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Reinforced Concrete ◽  
Modulus Of Elasticity ◽  
Dynamic Modulus ◽  
Structural Integrity ◽  
Gas Permeability ◽  
Ettringite Formation ◽  
Dynamic Modulus Of Elasticity ◽  
Pile Cap ◽  
Deterioration Process

Early deterioration of reinforced concrete foundations has been often reported in recent years. This process is usually characterized by an extensive mapping cracking process on concrete surfaces that results from several types of Internal Swelling Reaction (ISR). In this paper, a real case study of a tall reinforced concrete building with a severe deterioration process installed in its deep foundations is discussed. Laboratory tests were performed in concrete drilled cores extracted from a deep pile cap block 19 years after the beginning of construction. Tests to assess the compressive strength, the static and the dynamic modulus of elasticity, the gas permeability, and electron microscopy scanning to find out the primary mechanism responsible for the deterioration observed during in situ inspections. Chemical alterations of materials were observed in concrete cores, mainly due to Delayed Ettringite Formation (DEF), which significantly affected the integrity and durability of the structure. Dynamic modulus of elasticity showed to be a better indicator of damage induced by ISR in concrete than compressive strength. Procedures to strengthen the deteriorated elements using prestressing proved to be an efficient strategy to recover the structural integrity of pile caps deteriorated due to expansions due to ISR.

scholarly journals Preliminary Study on the Utilization of RHA as a Performance Enhancer for Rubber Mortar

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3216
Author(s):  
Jin Li ◽  
Peiyuan Chen ◽  
Haibing Cai ◽  
Ying Xu ◽  
Chunchao Li
Keyword(s):  
Compressive Strength ◽  
Mechanical Strength ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Capillary Absorption ◽  
Optimal Dosage ◽  
Positive Effects ◽  
Waste Rubber ◽  
Chloride Resistance ◽  
Preliminary Study

In this study, rice husk ash (RHA) was explored as a strength enhancer for mortars containing waste rubber. The effects of RHA on the flow, mechanical strength, chloride resistance, and capillary absorption of rubber mortar were investigated by substituting up to 20% cement with RHA. The experimental results showed that the incorporation of rubber into mortar could be safely achieved by adding RHA as a cement substitute by up to 20% without compromising the compressive strength of mortar. Moreover, the RHA also exerted positive effects on the enhancement of the chloride resistance as well as the capillary absorption of rubber mortars, for which 15% RHA was found to be the optimal dosage.

scholarly journals Effects of ring characteristics on the compressive strength and dynamic modulus of elasticity of seven softwood species

Holzforschung ◽  
2007 ◽  
Vol 61 (4) ◽  
pp. 414-418 ◽  
Author(s):  
Cheng-Jung Lin ◽  
Ming-Jer Tsai ◽  
Chia-Ju Lee ◽  
Song-Yung Wang ◽  
Lang-Dong Lin
Keyword(s):  
Compressive Strength ◽  
Statistical Analysis ◽  
Modulus Of Elasticity ◽  
Dynamic Modulus ◽  
Ring Width ◽  
Ring Density ◽  
Dynamic Modulus Of Elasticity ◽  
Wave Technique ◽  
Wood Strength ◽  
Softwood Species

Abstract The effects of ring characteristics on the compressive strength and dynamic modulus of elasticity of seven softwood species in Taiwan were examined. The results revealed good correlation between compressive strength and dynamic modulus of elasticity obtained using an ultrasonic wave technique (correlation coefficient r=0.77–0.86). Overall, compressive strength increased with decreasing ring width parameters and increasing ring density parameters. Ring density was related to compressive strength, but was not the sole factor affecting the wood strength. According to our statistical analysis, compressive strength was affected by various ring characteristics. Relationships between ring characteristics and compressive strength are influenced by the anatomic direction. Results revealed that earlywood density and minimum density in a ring are equally important variables for evaluating the compressive strength of wood.

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