scholarly journals Influence of Restrained Condition on Mechanical Properties, Frost Resistance, and Carbonation Resistance of Expansive Concrete

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2136
Author(s):  
Nguyen Duc Van ◽  
Emika Kuroiwa ◽  
Jihoon Kim ◽  
Hyeonggil Choi ◽  
Yukio Hama
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Frost Resistance ◽  
Total Porosity ◽  
Length Change ◽  
Ratio Test ◽  
Expansive Concrete ◽  
Restrained Condition ◽  
Carbonation Resistance ◽  
Compressive Strength Test

This paper presents the results of an experimental investigation of the effect of the restrained condition on the mechanical properties, frost resistance, and carbonation resistance of expansive concrete with different water–binder ratios. In this study, length change ratio test, expansion strain test, compressive strength test, mercury intrusion porosimetry test, underwater weighing test, freezing–thawing test, and accelerated carbonation test were performed to evaluate the mechanical properties, pore size distribution, total porosity, and durability of expansive concrete under both restrained and unrestrained conditions. The test results indicate that the length change ratio and expansion strain of the expansive concrete were controlled by the restrained condition. The compressive strength of expansive concrete was enhanced by the triaxial restraining when the amount of expansive additive was 40 kg/m3 of concrete. Two hypotheses were described to explain the change of pore structure change expansive mortar. The results also indicate that the carbonation resistance and frost resistance were improved by the uniaxial restrained condition. Furthermore, the effect of the restrained condition must be considered to evaluate not only the experimental results of the expansive concrete with a high EX replacement level but also the expansive concrete combining other cement replacement materials.

scholarly journals Carbonization Durability of Two Generations of Recycled Coarse Aggregate Concrete with Effect of Chloride Ion Corrosion

2020 ◽  
Vol 12 (24) ◽  
pp. 10544
Author(s):  
Chunhong Chen ◽  
Ronggui Liu ◽  
Pinghua Zhu ◽  
Hui Liu ◽  
Xinjie Wang
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Chloride Ion ◽  
Total Porosity ◽  
Recycled Concrete ◽  
Carbonation Depth ◽  
Aggregate Concrete ◽  
Recycled Coarse Aggregate ◽  
Carbonation Resistance ◽  
Two Generations

Carbonation durability is an important subject for recycled coarse aggregate concrete (RAC) applied to structural concrete. Extensive studies were carried out on the carbonation resistance of RAC under general environmental conditions, but limited researches investigated carbonation resistance when exposed to chloride ion corrosion, which is an essential aspect for reinforced concrete materials to be adopted in real-world applications. This paper presents a study on the carbonation durability of two generations of 100% RAC with the effect of chloride ion corrosion. The quality evolution of recycled concrete coarse aggregate (RCA) with the increasing recycling cycles was analyzed, and carbonation depth, compressive strength and the porosity of RAC were measured before and after chloride ion corrosion. The results show that the effect of chloride ion corrosion negatively affected the carbonation resistance of RAC, and the negative effect was more severe with the increasing recycling cycles of RCA. Chloride ion corrosion led to a decrease in compressive strength, while an increase in carbonation depth and the porosity of RAC. The equation of concrete total porosity and carbonation depth was established, which could effectively judge the deterioration of carbonation resistance of RAC.

Study on the Mechanical Properties and Frost Resistance of Recycled Concrete Prepared by Village Construction Wastes

2011 ◽  
Vol 418-420 ◽  
pp. 406-410
Author(s):  
Jun Liu ◽  
Yao Li ◽  
Dan Dan Hong ◽  
Yu Liu
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Frost Resistance ◽  
Cement Mortar ◽  
Strength Loss ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Replacement Rate ◽  
Concrete Mechanical Properties ◽  
Better Than

Abstract. Recycled aggregate—rural building material wastes pretreated by cement mortar—are applied into concrete with different replacement rates: 0, 25%, 50%, 75%, and 100%. Results from measurements of compressive strength, cleavage tensile strength, mass loss after fast freeze-thaw cycles, and compressive strength loss indicate that a different recycled aggregate replacement rate certainly influences concrete mechanical properties and frost resistance. Recycled aggregate replacement rates less than 75% performs better than common concrete. Data from the 100% replacement rate is worse than that of rates less than 75% but still satisfy the general demands of GB standard on C30 concrete.

The Influence of Pore-Strucrure on the Campressive Strength of Hardened Cement Paste

1984 ◽  
Vol 42 ◽  
Author(s):  
Huang Yiun-Yuan ◽  
Ding Wei ◽  
Lu Ping
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Pore Structure ◽  
Cement Paste ◽  
Total Porosity ◽  
Hardened Cement ◽  
Hardened Cement Paste ◽  
New Information ◽  
The Relationship ◽  
Empirical Constants

AbstractThe pore-structure strongly influences the carpressive strength of hardened cement paste (hcp) and other porous materials, as well as other mechanical properties. The simplest but most currently used expression representing the relationship between the pore-structure and compressive strength is fram Balshin: σ = σ0 (l-P)A, in which only the total porosity P is involved as a single parameter and σ0 and A are empirical constants. The influence of pore size distribution and pore shapes etc. are not considered.The authors introduce second parameter w - the factor of relative specific surface area of the pores other than the total porosity P into consideration and a new expression is proposed:σc=K11-p/1+2p(K2(1-p))K3w+K4 all the constants K1 - K4 can be determined experimentally. By using of this expression the new information relating the influence of pore-structure on the caopressive strength of hcp can be predicted.

Influence the Carbonation Resistance and Mechanical Properties of Shotcrete by Accelerated Carbonation Test

2014 ◽  
Vol 1065-1069 ◽  
pp. 1985-1989
Author(s):  
Jia Bin Wang ◽  
Di Tao Niu ◽  
Rui Ma ◽  
Ze Long Mi
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Steel Fiber ◽  
Splitting Tensile Strength ◽  
Construction Technology ◽  
Accelerated Carbonation ◽  
Carbonation Depth ◽  
Normal Concrete ◽  
Carbonation Resistance

In order to investigate the carbonation resistance of shotcrete and the mechanical properties after carbonation, the accelerated carbonation test was carried out. The results indicate that the carbonation resistance of shotcrete is superior to that of normal concrete. With the increasing of carbonation depth, compressive strength and splitting tensile strength of shotcrete grew rapidly. The admixing of steel fiber can further improve the carbonation resistance, reduce the carbonation rate, and increase the splitting tensile strength of shotcrete greatly. Besides, based on analyzing the effects of construction technology and steel fiber of concrete for the carbonation resistance, a carbonation depth model for shotcrete was established. Key words: shotcrete; carbonation; steel fiber; mechanical properties

scholarly journals Influence of Mullite Wool Waste on the Properties of Ceramics

1970 ◽  
Vol 17 (1) ◽  
pp. 80-85
Author(s):  
Jurgita MALAIŠKIENĖ
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Water Absorption ◽  
Firing Temperature ◽  
Frost Resistance ◽  
Effective Porosity ◽  
Flow Reserve ◽  
Optimum Quantity ◽  
Ceramic Samples ◽  
Porous Volume

In the paper, the influence of mullite wool waste additive on the properties of building ceramics is analysed. For that purpose four formation masses were prepared, dried and fired at the analogous regimes (maximum firing temperature 1080 °C). The fired samples were used to determine the structural and physical-mechanical properties. The values of these parameters are analysed: water absorption, total and effective porosity, rate of capillary mass flow, reserve of porous volume, compressive strength, density and estimated exploitation frost resistance. It has been determined that mullite wool waste can be applied to the production of building ceramics and the optimum quantity of waste in a formation mass is 10 % according to weight. Water absorption of those ceramic samples was less than 4 %, compressive strength was 28.6 MPa, density - 2033 kg/m3, forecasted resistance to frost about 400 cycles.http://dx.doi.org/10.5755/j01.ms.17.1.255

Experiment and Mechanism Study on Effect of Water/Binder and Fly Ash on Mechanical Properties of HPC

2011 ◽  
Vol 255-260 ◽  
pp. 3404-3410
Author(s):  
Shuang Xi Li ◽  
An Quan Xu ◽  
Xin Jun Tang ◽  
Quan Hu
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Fly Ash ◽  
Concrete Strength ◽  
Early Period ◽  
Point Of View ◽  
Mechanism Study ◽  
Compressive Strength Test ◽  
Large Water

It takes on the technical and economic double benefits that fly ash taking the place of cement. However, water/binder of modern concrete is generally low; the research on the concrete performance which is based on large water/binder is no longer suitable for analysis of modern concrete. As to this problem, using different proportions of W/B and FA dosage as influencing factors, specimen is compounded for the compressive strength test. Then, mechanical properties of HPC are studied systematically. Based on this, macro-performance is analyzed from a micro-mechanism point of view through taking the electron micrograph. As the study shows, strength of HPC mixed with fly ash has low characteristics at early period while high ones at later period. At later hydration, fly ash effect plays a significant role, the growth rate of concrete strength increases as the increase of FA dosage. Compressive strength of concrete decreases as the increase of W/B and FA dosage. When the W/B is high, compressive strength is not sensitive to the change of W/B and FA dosage; but when the W/B decreases from 0.30 to 0.25, the concrete strength transition occurs. The influence of W/B on concrete compressive strength is more significant than that of the FA dosage; in the preparation of HPC, fly ash can be added more and cement is added less relatively by decreasing the W/B, displaying the role of micro-aggregate filling and modification, improving the strength and other performance of concrete. The study on micro-mechanism proves well the macro-phenomena above.

Laboratory Experimental Research on Mix Ratio Test of Cement Soil

2013 ◽  
Vol 438-439 ◽  
pp. 197-201
Author(s):  
Xian Hua Yao ◽  
Peng Li ◽  
Jun Feng Guan
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Cement Content ◽  
Ratio Test ◽  
Curing Time ◽  
Curing Conditions ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Cement Soil

Based on the generalization and analysis of laboratory experimental results on mix ratio, the effects of various factors such as cement content, water-cement ratio, curing time, curing conditions and types of cement on the mechanical properties of unconfined compressive strength of cement soil are presented. Results show that the unconfined compressive strength of cement soil increases with the growing curing time, and it is greatly affected by the cement content, water-cement ratio, cement types and curing time, while the effect of curing conditions is weak with a cement content of more than 10%. Moreover, the stress-strain of the cement soil responds with the cement content and curing time, increasing curing time and cement content makes the cement soil to be harder and brittle, and leads to a larger Young's modulus.

Low Strength Self Compacting Concrete Compressive Strength Test

2013 ◽  
Vol 275-277 ◽  
pp. 2041-2044
Author(s):  
Feng Yan ◽  
Nan Pang
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Compression Strength ◽  
Strength Test ◽  
The Self ◽  
Concrete Compressive Strength ◽  
Self Compacting Concrete ◽  
Intensity Index ◽  
Compressive Strength Test ◽  
Low Strength

In this paper,the mechanical properties were studied,the self compacting concrete cubic compression strength,prismatic compressive strength test,discussed two kinds of relationship between intensity index.

scholarly journals PENGARUH CANGKANG KEMIRI SEBAGAI PENGGANTI AGREGAT KASAR TERHADAP SIFAT MEKANIK BETON (EFFECT OF CANDLENUT SHELL AS SUBTITUTE COARSE AGGREGATE TO THE MECHANICAL PROPERTIES OF CONCRETE)

2018 ◽  
Author(s):  
Erniati Bachtiar
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Coarse Aggregate ◽  
Concrete Mixture ◽  
Construction Technology ◽  
Concrete Compressive Strength ◽  
Coarse Aggregates ◽  
Volume Weight ◽  
Compressive Strength Test

Concrete construction technology is directed to be sustainable and ecofriendly. The waste of the candlenut shell as a substitute for the coarse aggregate of concrete mixture is known that the candlenut shell has a hard texture so it may be used as a substitute for coarse aggregates in concrete. The purpose of the research was to determine the effect of Candlenut shell as a substitute of coarse aggregate on physical properties (slump test, bleeding, segregation, volume weight) and mechanical properties (compressive strength and tensile strength) of concrete using Candlenut shell as replacement material of the coarse aggregate. The variation of the research was percentage of the Candlenut shell in the concrete mixture, that was 0%, 25%, 50%, 75% and 100% to the coarse aggregate volume in the concrete mixture. Number of specimens in reseach was each 5 pieces each variation. Testing of mechanical properties of concrete (compressive strength and tensile strength) was performed at 28 days. Testing of the concrete for compressive strength test and tensile strength on age 28 days. Concrete using candlenut shell as a substitute of coarse aggregates has decreased compressive strength respectively 11.72 MPa (37.71%) for 25% candlenut shell; 15.54 MPa (50.00%) for 50% candlenut shell; 18.35 MPa (59.02%) for 75% candlenut shell; And 18,85 MPa (60,66%) for 100% candlenut shell from of the 0% candlenut shell with compressive strength of 31.08 Mpa. Concrete using for 25% candlenut shell as a substitute for coarse aggregates decreased tensile strength respectively of 0.95 MPa (28.70%) for 25% candlenut shell; 1.21 MPa (36.56%) for 50% candlenut shell; 1.27 MPa (38.37%) for 75% candlenut shell; And 1.40 MPa (42.30%) for 100% candlenut shell from of the 0% candlenut shell with the tensile strength of BN of 3.31 MPa. The decrease in the value of compressive strength and tensile strength is strongly influenced by the increasing percentage of Candlenut shells on concrete

scholarly journals KARAKTERISTIK SELF COMPACTING CONCRETE (SCC) TANPA CURING

2018 ◽  
Author(s):  
erniati
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Fresh Concrete ◽  
Strength Test ◽  
Splitting Tensile Strength ◽  
Good Resistance ◽  
Self Compacting Concrete ◽  
Compressive Strength Test ◽  
Resistance Durability

Self Compacting Concrete (SCC) is one solution to get concrete construction which it has good resistance. Durability of concrete was obtained by the good concrete compaction to be done by a skilled workforce. However, one of the negligence that often occur in the field ie after casting they was ignoring curing of the hardening concrete. This study discusses the workability of fresh concrete and mechanical properties (compressive strength and splitting tensile strength) on SCC without curing. Testing of the concrete workability based on EFNARC standard. The mechanical properties test based on ASTM standards. The method Compressive strength test based on ASTM standards 39 / C 39M - 12a, whereas splitting tensile strength accordance standard ASTM C496 / C496M-11. The results of the study indicate that the SCC without curing effect on the reduction in compressive strength at ages 1, 3, 7, 28, and 90 days in a row at 4.11 MPa (16.1%); 4.90 MPa (13.9%); 6.64 MPa (13.1%); and 6, 72 MPa (12.75%). Splitting tensile strength decreased respectively by 0.1 MPa (3.25%); 0.26 MPa (7.99%); 0.4 MPa (9.52%); and 0.39 MPa (9.16%).

Sign in / Sign up

Export Citation Format

Share Document