The Study of Mechanical Properties of Structural Lightweight Concrete

2010 ◽  
Vol 97-101 ◽  
pp. 1620-1623 ◽  
Author(s):  
Hong Zhi Cui ◽  
Feng Xing
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Bond Strength ◽  
Modulus Of Elasticity ◽  
Lightweight Concrete ◽  
Experimental Studies ◽  
Lightweight Aggregate ◽  
Experimental Results ◽  
The Relationship

Many investigations have been conducted on compressive strength of lightweight aggregate concretes (LWAC), but there are few experimental studies on the relationship between compressive strength, bond strength and elastic modulus of LWAC. In this paper, the specimens of twenty kinds of LWACs with different mix proportions were made. Properties of compressive strength, bond strength and modulus of elasticity of the LWACs were tested. Based on the testing resulting, equations for relationship between bond strength and compressive strength of the LWAC were established. For LWAC modulus of elasticity, the experimental results of this study can fit well with predicted equation of ACI 318

The Relationship between Mechanical Properties and Shrinkage of the Concretes Used in Florida

2012 ◽  
Vol 204-208 ◽  
pp. 3799-3804
Author(s):  
Yan Jun Liu ◽  
Mang Tia
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Empirical Relationship ◽  
Lightweight Aggregate ◽  
Shrinkage Strain ◽  
Coarse Aggregates ◽  
Concrete Mixtures ◽  
The Relationship ◽  
Mineral Additives

This paper investigated the mechanical strength and shrinkage properties of the concrete mixtures frequently used in Florida. The concrete mixtures were proportioned with three different types of coarse aggregates, such as Miami Oolite limestone, Georgia granite and Stalite lightweight aggregate, and two mineral additives, including fly ash and slag. And fourteen concrete mixtures were evaluated on their characteristics of compressive strength, elastic modulus and shrinkage for 91 days. The empirical relationship between the mechanical properties of concretes and shrinkage strain was analyzed mathematically. The results indicate that the compressive strength and elastic modulus of concrete are exponentially related the shrinkage strain of concrete. The finding from this study is agreeable with that by Troxell et al [5]. Also, the effectiveness of ACI 209 and CEB-FIP models on predicting the shrinkage behavior of concretes used frequently in Florida was evaluated. The result indicates that CEB-FIP model gives more reliable prediction than ACI 209 model does.

scholarly journals Efficiency factor and modulus of elasticity of lightweight concrete with expanded clay aggregate

2010 ◽  
Vol 3 (2) ◽  
pp. 195-204 ◽  
Author(s):  
W.G Moravia ◽  
A. G. Gumieri ◽  
W. L. Vasconcelos
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Large Scale ◽  
Lightweight Concrete ◽  
Weight Ratio ◽  
Lightweight Aggregate ◽  
Normal Weight ◽  
Lightweight Aggregate Concrete ◽  
Empirical Methods ◽  
Normal Weight Concrete

Nowadays lightweight concrete is used on a large scale for structural purposes and to reduce the self-weight of structures. Specific grav- ity, compressive strength, strength/weight ratio and modulus of elasticity are important factors in the mechanical behavior of structures. This work studies these properties in lightweight aggregate concrete (LWAC) and normal-weight concrete (NWC), comparing them. Spe- cific gravity was evaluated in the fresh and hardened states. Four mixture proportions were adopted to evaluate compressive strength. For each proposed mixture proportion of the two concretes, cylindrical specimens were molded and tested at ages of 3, 7 and 28 days. The modulus of elasticity of the NWC and LWAC was analyzed by static, dynamic and empirical methods. The results show a larger strength/ weight ratio for LWAC, although this concrete presented lower compressive strength.

COMPRESSIVE STRENGTH EVALUATION OF LIGHTWEIGHT CONCRETE WITH EXPANDED GLASS AGGREGATE BY ULTRASONIC PULSE VELOCITY METHOD

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Christopher Collins ◽  
Saman Hedjazi
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Lightweight Concrete ◽  
Lightweight Aggregate ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Normal Weight ◽  
Unit Weight ◽  
Normal Weight Concrete

In the present study, a non-destructive testing method was utilized to assess the mechanical properties of lightweight and normal-weight concrete specimens. The experiment program consisted of more than a hundred concrete specimens with the unit weight ranging from around 850 to 2250 kg/m3. Compressive strength tests were performed at the age of seven and twenty eight days. Ultrasonic Pulse Velocity (UPV) was the NDT that was implemented in this study to investigate the significance of the correlation between UPV and compressive strength of lightweight concrete specimens. Water to cement ratio (w/c), mix designs, aggregate volume, and the amount of normal weight coarse and fine aggregates replaced with lightweight aggregate, are the variables in this work. The lightweight aggregate used in this study, Poraver®, is a product of recycled glass materials. Furthermore, the validity of the current prediction methods in the literature was investigated including comparison between this study and an available expression in the literature on similar materials, for calculation of mechanical properties of lightweight concrete based on pulse velocity. It was observed that the recently developed empirical equation would better predict the compressive strength of lightweight concrete specimens in terms of the pulse velocity.

Study on Mechanical Properties of Iron Wire Cement Mortar

2012 ◽  
Vol 594-597 ◽  
pp. 816-819
Author(s):  
Zhi Hao Liu ◽  
Chuan Xiao Liu ◽  
Dong Chen Huang ◽  
Long Wang
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Uniaxial Compression ◽  
Compression Test ◽  
Cement Mortar ◽  
Experimental Results ◽  
Uniaxial Compression Test ◽  
Mass Ratio ◽  
Iron Wire

Through the uniaxial compression test, the mechanical properties of different placements of iron wire cement mortar, e.g. compressive strength and elastic modulus, were studied, and the mass ratios of cement, sands and water influencing the mechanical properties were put forward, which provided the experimental results for reference for the wide use of the iron wire cement mortar material. From the study it is gained that: (1) The best placement of the iron wires in cement mortar is horizontal. (2) The best mass ratio of the cement, sands and water is 1:4.70:0.81.

scholarly journals Research on the Mechanical Properties and NMR Characteristics of Cement Mortar during Freeze-Thaw Cycles

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Taoying Liu ◽  
Yunmin Wang ◽  
Keping Zhou ◽  
Feng Gao ◽  
Shenghua Xie
Keyword(s):  
Mechanical Properties ◽  
Nuclear Magnetic Resonance ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Cement Mortar ◽  
Freeze Thaw ◽  
Low Field ◽  
First Time ◽  
The Relationship

Low-field nuclear magnetic resonance (NMR) technology has the characteristics of nondestructive, rapid, and accurate. In the present paper, the mechanical properties and the size and distribution of pores of cement mortar during freeze-thaw cycles were studied by using the NMR technology for the first time. The change law of surface and quality, compressive strength, splitting tensile strength, and elastic modulus of cement mortar under 0, 25, 50, 75, and 100 freeze-thaw cycles were studied. And the changes of T2 spectra of cement mortar under different freeze-thaw environments were analyzed; the change rule between freeze-thaw cycles and the size of the pore within the cement mortar were also obtained. Moreover, the relationship between the mechanical properties and the pore structure of cement mortar was studied.

scholarly journals PERFORMANCE OF HIGH STRENGTH LIGHTWEIGHT CONCRETE USING PALM WASTES

2018 ◽  
Vol 19 (2) ◽  
pp. 30-42
Author(s):  
Md. Nazmul Huda ◽  
Mohd Zamin Jumaat ◽  
A. B. M. Saiful Islam ◽  
Walid A. Al-Kutti
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Coarse Aggregate ◽  
Lightweight Concrete ◽  
High Strength ◽  
Splitting Tensile Strength ◽  
Palm Shell

The performance of high strength structural lightweight concrete (LWC) using the palm wastes, oil palm shell (OPS) as well as palm oil clinker (POC) has been reported. Existing literatures used either OPS or POC individually for production of LWC. Each concept has their own advantages-disadvantages. In this study, both OPS and POC have been put together as coarse aggregate on the way to see the improvement of mechanical properties of waste based LWC. To achieve this purpose, regular coarse aggregate has been fully replaced by OPS and POC in the concrete. This structural grade lightweight concrete is named as palm shell and clinker concrete (PSCC). Attempts have been made with the series of OPS and POC mixture aimed at identifying for better performance. The quantity of OPS and POC mix has been varied as 30%, 40%, 50%, 60% and 70%. Mechanical properties of PSCC like density, workability, compressive strength at different ages, flexural strength, splitting tensile strength as well as modulus of elasticity have been evaluated. It is revealed that the proposed PSCC has extensive potential in terms of high compressive strength and good material behavior to perform as a better LWC. The study could offer structural lightweight concrete of compressive strength up to 46 MPa that is 31% higher than the control mix. The usage of 50% OPS to 50% POC coarse aggregate by vol. in the concrete mix is found to be the optimum mix. Furthermore, simple correlations have been developed which can easily predict compressive strength, splitting tensile strength, flexural strength, modulus of elasticity and ultrasonic pulse velocity of lightweight concrete.

Performances of Artificial Lightweight Geopolymer Aggregate (ALGA) in OPC Concrete

2016 ◽  
Vol 673 ◽  
pp. 29-35 ◽  
Author(s):  
R.A. Razak ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Kamarudin Hussin ◽  
Khairul Nizar Ismail ◽  
D. Hardjito ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Water Absorption ◽  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Lightweight Concrete ◽  
Lightweight Aggregate ◽  
High Volume ◽  
Alkaline Activator ◽  
Geopolymer Paste

The non-availability of natural lightweight aggregate and demand are increasing in worldwide, thus new alternatives on producing artificial aggregate should be developed. This paper discussed on the mechanical properties of artificial lightweight geopolymer aggregate (ALGA) made from LUSI mud and alkaline activator in concrete. LUSI means Sidoarjo mud from Indonesia which erupted on 2006 with high volume and impacted an area of almost 770 hectare. The alkaline activator used was combination of sodium hydroxide and sodium silicate. The geopolymer paste formed need to be pelleted and sintered at 950 °C. The results showed that the compressive strength of OPC-ALGA concrete is 41.89 MPa at 28 days of testing with a density of 1760.1 kg/m3 which can be classified as lightweight concrete. The water absorption of ALGA concrete is 2.77%.

scholarly journals Experimental Analysis of the Mechanical Properties and Resistivity of Tectonic Coal Samples with Different Particle Sizes

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2303
Author(s):  
Congyu Zhong ◽  
Liwen Cao ◽  
Jishi Geng ◽  
Zhihao Jiang ◽  
Shuai Zhang
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Uniaxial Compressive Strength ◽  
Coalbed Methane ◽  
Coal Sample ◽  
Fine Particles ◽  
Particle Sizes ◽  
Tectonic Coal

Because of its weak cementation and abundant pores and cracks, it is difficult to obtain suitable samples of tectonic coal to test its mechanical properties. Therefore, the research and development of coalbed methane drilling and mining technology are restricted. In this study, tectonic coal samples are remodeled with different particle sizes to test the mechanical parameters and loading resistivity. The research results show that the particle size and gradation of tectonic coal significantly impact its uniaxial compressive strength and elastic modulus and affect changes in resistivity. As the converted particle size increases, the uniaxial compressive strength and elastic modulus decrease first and then tend to remain unchanged. The strength of the single-particle gradation coal sample decreases from 0.867 to 0.433 MPa and the elastic modulus decreases from 59.28 to 41.63 MPa with increasing particle size. The change in resistivity of the coal sample increases with increasing particle size, and the degree of resistivity variation decreases during the coal sample failure stage. In composite-particle gradation, the proportion of fine particles in the tectonic coal sample increases from 33% to 80%. Its strength and elastic modulus increase from 0.996 to 1.31 MPa and 83.96 to 125.4 MPa, respectively, and the resistivity change degree decreases. The proportion of medium particles or coarse particles increases, and the sample strength, elastic modulus, and resistivity changes all decrease.

scholarly journals Undergraduate Research Program to Recycle Composite Waste

2021 ◽  
Vol 11 (7) ◽  
pp. 354
Author(s):  
Waleed Ahmed ◽  
Essam Zaneldin ◽  
Amged Al Hassan
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Carbon Fiber ◽  
Undergraduate Students ◽  
Research Program ◽  
Modulus Of Elasticity ◽  
Undergraduate Research ◽  
Undergraduate Research Program ◽  
Structural Applications ◽  
Cfrp Composite

With the rapid growth in the manufacturing industry and increased urbanization, higher amounts of composite material waste are being produced, causing severe threats to the environment. These environmental concerns, coupled with the fact that undergraduate students typically have minimal experience in research, have initiated the need at the UAE University to promote research among undergraduate students, leading to the development of a summer undergraduate research program. In this study, a recycling methodology is presented to test lab-fabricated Carbon-Fiber-Reinforced Polymer (CFRP) for potential applications in industrial composite waste. The work was conducted by two groups of undergraduate students at the UAE University. The methodology involved the chemical dissolution of the composite waste, followed by compression molding and adequate heat treatment for rapid curing of CFRP. Subsequently, the CFRP samples were divided into three groups based on their geometrical distinctions. The mechanical properties (i.e., modulus of elasticity and compressive strength) were determined through material testing, and the results were then compared with steel for prompt reference. The results revealed that the values of mechanical properties range from 2 to 4.3 GPa for the modulus of elasticity and from 203.7 to 301.5 MPa for the compressive strength. These values are considered competitive and optimal, and as such, carbon fiber waste can be used as an alternate material for various structural applications. The inconsistencies in the values are due to discrepancies in the procedure as a result of the lack of specialized equipment for handling CFRP waste material. The study concluded that the properties of CFRP composite prepreg scrap tend to be reusable instead of disposable. Despite the meager experimental discrepancies, test values and mechanical properties indicate that CFRP composite can be successfully used as a material for nonstructural applications.

scholarly journals Effects of carbon nanotubes on expanded glass and silica aerogel based lightweight concrete

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Suman Kumar Adhikary ◽  
Žymantas Rudžionis ◽  
Simona Tučkutė ◽  
Deepankar Kumar Ashish
Keyword(s):  
Carbon Nanotubes ◽  
Compressive Strength ◽  
Silica Aerogel ◽  
Lightweight Concrete ◽  
Lightweight Aggregate ◽  
Cementitious Materials ◽  
Lightweight Aggregate Concrete ◽  
Multi Wall Carbon Nanotubes ◽  
Sem Image ◽  
Study Results

AbstractThis study is aimed to investigate the effect of carbon nanotubes on the properties of lightweight aggregate concrete containing expanded glass and silica aerogel. Combinations of expanded glass (55%) and hydrophobic silica aerogel particles (45%) were used as lightweight aggregates. Carbon nanotubes were sonicated in the water with polycarboxylate superplasticizer by ultrasonication energy for 3 min. Study results show that incorporating multi-wall carbon nanotubes significantly influences the compressive strength and microstructural performance of aerogel based lightweight concrete. The addition of carbon nanotubes gained almost 41% improvement in compressive strength. SEM image of lightweight concrete shows a homogeneous dispersal of carbon nanotubes within the concrete structure. SEM image of the composite shows presence of C–S–H gel surrounding the carbon nanotubes, which confirms the cites of nanotubes for the higher growth of C–S–H gel. Besides, agglomeration of carbon nanotubes and the presence of ettringites was observed in the transition zone between the silica aerogel and cementitious materials. Additionally, flowability, water absorption, microscopy, X-ray powder diffraction, and semi-adiabatic calorimetry results were analyzed in this study.

Sign in / Sign up

Export Citation Format

Share Document