Experimental Research on Compressive Strength and Storage Period for Dry-Mixed Material of Shotcrete

2010 ◽  
Vol 168-170 ◽  
pp. 1501-1505
Author(s):  
Jing Shuang Zhang ◽  
Qin Yong Ma ◽  
Xing Teng Han
Keyword(s):  
Compressive Strength ◽  
Water Content ◽  
Experimental Research ◽  
Loss Rate ◽  
Raw Materials ◽  
Engineering Application ◽  
Storage Period ◽  
Strength Loss ◽  
Mix Proportion ◽  
And Storage

According to dry-mixed materials of shotcrete which composed of raw materials in mix proportion the concrete quality as field mixing were included. Through the experimental research on the storage period of using dry-mixed materials in shotcrete, variations of compressive strength were obtained. In according with the studies on the storage period of dry-mixed materials in 7d, 11d, 15d, 20d and 28d, compared with 0d, the loss of compressive strength were obtained under different sand water content (0%, 0.5% and 1.0%). The results shown that strength loss rate of C30 concrete was 6.7% when the sand water content was 0.5% in the 28d and while strength loss rate was 12.0% when the sand water content was 1.0%. The studies on storage period provide supports to the using of dry-mixed shotcrete in engineering application.

scholarly journals Effect of washing time and storage of raw Material on Surimi and Kamaboko of Tilapia (Oreochromis sp.)

2020 ◽  
Vol 7 (3) ◽  
pp. 89
Author(s):  
Eka Saputra
Keyword(s):  
Water Content ◽  
Raw Materials ◽  
Frozen Storage ◽  
Storage Period ◽  
Raw Material ◽  
Minced Fish ◽  
Materials Used ◽  
And Storage

This study aim was to determine the effect of washing and raw materials on frozen storage on the quality of surimi and kamaboko from raw material of tilapia (Oreochromis sp). There were three types of raw materials used, namely minced fish, surimi, and surimi with addition of sorbitol, with three washing treatments and four weeks frozen storage period observed every week. The method used consisted of measurements of pH, water content, bite test, and folding test. Then the results obtained for the best kamaboko tilapia (Oreochromis sp) were obtained from fillet raw materials compared to the raw material of Minced fish and raw materials of Minced Fish + Sorbitol, with a frequency of washing once and frozen storage for 3 weeks.

scholarly journals Fiber-Reinforced Sand-Fixing Board Based on the Concept of “Sand Control with Sand”: Experimental Design, Testing, and Application

2021 ◽  
Vol 13 (18) ◽  
pp. 10229
Author(s):  
Bosong Ding ◽  
Jianjun Cheng ◽  
Duotian Xia ◽  
Xiao Wu ◽  
Li Gao ◽  
...  
Keyword(s):  
Loss Rate ◽  
Raw Materials ◽  
Mass Loss Rate ◽  
Engineering Application ◽  
Strength Loss ◽  
Fiber Content ◽  
Enhancement Effect ◽  
Aeolian Sand ◽  
Maximum Increase ◽  
Sand Control

Harsh conditions, such as the lack of raw materials and high transportation costs, impede the construction of desert railway sand control projects. Against this background, aeolian sand along the desert railway was used in a study on “sand control with sand.” According to the mechanical properties and durability tests, as well as field observations, the enhancement effect of fiber (cloth) on the performance of a sand-fixing board made of aeolian sand was analyzed. Based on the results, the mechanical strength of the sand-fixing board increased with increasing fiber content and length, and the maximum increase in compressive strength and flexural strength reached 2.15 and 0.59 times, respectively. The addition of fiber significantly improved the frost resistance, effectively reducing the mass loss rate of the board by an average of 60%. With increasing fiber content and length, the improvement effect of the freeze–thaw strength loss rate of the sand-fixing board first decreased and then increased. The results show that the performance of sand-fixing boards reached the engineering application standard under the reinforcement of the fiber (cloth), successfully establishing the concept of “sand control with sand.”

scholarly journals Experimental Study on Mechanical Properties of High-Ductility Concrete against Combined Sulfate Attack and Dry–Wet Cycles

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4035
Author(s):  
Lingling Li ◽  
Junping Shi ◽  
Jialiang Kou
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Loss Rate ◽  
Rapid Development ◽  
Engineering Application ◽  
Sulfate Solution ◽  
Strength Loss ◽  
Sulfate Attack ◽  
High Ductility ◽  
Chemical Attack

Concrete will deteriorate and damage under sulfate attack. In order to study the degradation characteristics of HDC under sulfate attack, the mechanical properties of high-ductility concrete (HDC) were investigated using the uniaxial compressive strength test of HDC specimens soaked in different concentrations of sulfate solution and subjected to different times of dry–wet cycles. The variations in the compressive strength, loss rate of compressive strength, and the max compressive strength under the action of sulfate attack and dry–wet cycles were analyzed. The analytical expressions of damage variables were given. SEM was used to observe the microstructure of the sample, and the microdamage mechanism of the HDC was explored. The deterioration of the HDC was found to be the result of the combined action of sulfate attack and dry–wet cycles and was caused by physical attack and chemical attack. PVA prevented the rapid development of deterioration. On the basis of the change of compressive strength, the damage variable was established to quantitatively describe the degree of damage to HDC. The experimental results showed that with the increase in the number of dry–wet cycles, the compressive strength of HDC generally increased first and then decreased. As the concentration of the sulfate solution increased, the loss rate of the compressive strength of HDC generally increased and the max compressive strength gradually decreased. With the increase in the number of dry–wet cycles, HDC first showed self-compacting characteristics and then gradually became destroyed. Compared with ordinary concrete (OC), HDC is superior to OC in sulfate resistance and dry–wet cycles. This study provided a test basis for the engineering application of HDC in sulfate attack and dry–wet cycles environment.

Fireproof Performance of Foam Concrete Insulation Board

2011 ◽  
Vol 250-253 ◽  
pp. 474-479
Author(s):  
Shui Jun Yu ◽  
Yu Long Wang ◽  
Ben Jie Duan ◽  
Jun Wei Zhou ◽  
Fei Yang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Water Content ◽  
Loss Rate ◽  
Strength Loss ◽  
Building Energy ◽  
Fire Performance ◽  
Foam Concrete ◽  
Calcination Time ◽  
Standard Specimens ◽  
Building Energy Saving

Foam concrete is used in building energy-saving insulation works, to study its fire performance is very important for further enhancing the fire performance of buildings. Under simulated fire conditions, by determining the compressive strength of foam concrete at different densities, different calcination time and different water content, this experiment studies the effect of these conditions on the fire performance of foam concrete. The results show that in case of fire, the compressive strength loss rate of foam concrete increases with the decreasing of density; to calcine the foam concrete standard specimens whose density are 300kg/m3 and 800kg/m3, their strength loss rates are 66.3% and 25.5%, the compressive strength of foam concrete in the same density increases with the calcination time decreasing, water content has different effects on different densities of foam concrete in the fire security. The foam concrete is non-flammable, but its compressive strength decreases due to the fire of combustible materials and high-temperature calcination.

Effect of Mica Content in Stone Powder of Manufactured Sand on Performance of Cement Mortar

2014 ◽  
Vol 1044-1045 ◽  
pp. 624-628
Author(s):  
Jie Quan Xing ◽  
Shu Lin Zhan ◽  
Xin Yu Li
Keyword(s):  
Compressive Strength ◽  
Loss Rate ◽  
Cement Mortar ◽  
Mass Loss Rate ◽  
Strength Loss ◽  
Freezing Resistance ◽  
River Sand ◽  
Manufactured Sand ◽  
Freeze Thaw ◽  
Different Content

This paper studies the influence on compressive strength, freezing resistance and microstructure of cement mortar with different content of mica in stone powder, in the tests, manufactured sand with high content of mica and natural river sand were mixed with different proportion, and the content of stone powder was the same in mixed sand. Experiment results indicate that, with the increasing of mica content in stone powder, 28d and 60d compressive strength of cement mortar decreases obvious, mass loss rate and strength loss rate with 50 freeze-thaw cycles increase a little. Microstructure of cement mortar with higher content of mica is not compactly by SEM, the internal defects of cement hardened pastes could be increased because of the flake mica which surface is smooth, and it will cause the spread of micro crack.

scholarly journals Mix Proportion of Lightweight Straw Ceramsite Concrete

CONVERTER ◽  
2021 ◽  
pp. 110-117
Author(s):  
Yanxia Huang
Keyword(s):  
Compressive Strength ◽  
Lightweight Concrete ◽  
Concrete Strength ◽  
Engineering Application ◽  
Volumetric Method ◽  
Comprehensive Utilization ◽  
Mix Proportion ◽  
Concrete Mix ◽  
Straw Burning ◽  
The Impact

To reduce air pollution of straw burning, and also to improve the ratio of straw comprehensive utilization, this paper presents a lightweight concrete with straw based on the mix proportion research. Firstly, the mix proportion of lightweight ceramsite concrete was designed by a volumetric method. Then, a series of lightweight ceramsite concrete mix proportion experiments were conducted to verify the validity of the design and to evaluate the effect of the admixtures on the performance of the concrete. Finally, the lightweight straw ceramsite concrete mix proportion experiments were conducted by adding straw to lightweight ceramsite concrete for studying the impact of the straw amount on the concrete strength and density. The experimental results show that the compressive strength of lightweight straw ceramsite concrete can reach the requirement of engineering application. The concrete strength and density were descended obviously with the increasing of straw amount. It was suggested that the straw amount should be limited in 20% of the concrete volume.

Experimental Study of Composite High Strength Self-Compacting Concrete

2017 ◽  
Vol 865 ◽  
pp. 289-294
Author(s):  
Xi Ri Kang ◽  
Guang Xiu Fang
Keyword(s):  
Compressive Strength ◽  
Engineering Application ◽  
High Strength ◽  
Cementitious Material ◽  
Self Compacting Concrete ◽  
Design Strength ◽  
Mix Proportion ◽  
Optimal Mix ◽  
Axial Compressive Strength ◽  
Compressive Strength Of Concrete

This test uses polycarboxylate superplasticizer by adding 15% quantitative fly ash, 10%, 15%, 20% of slag, and 5%,7.5%, 10% of silica fume of the total amount of the cementitious material to be an equivalent replacement for cement. Ordinary materials were used to make the C70 high strength self-compacting concrete. The concrete slump, expansion degree, and the axial compressive strength of concrete were studied. Through testing, the mix proportion of each group of concrete slump was determined to be above 250mm. And the expansion degree to be above 550mm. The axial compressive strength satisfied the design strength value. At the same time, the optimal mix ratio was proposed. And the economic performance of each group was analyzed. There are references for a similar experimental design and engineering application.

Optimizing Mix Proportion of Lightweight Concrete Containing Plastic Waste by Taguchi Method

2014 ◽  
Vol 931-932 ◽  
pp. 431-435 ◽  
Author(s):  
Nattakan Dulsang ◽  
Prinya Chindaprasirt ◽  
Patcharapol Posi ◽  
Salim Hiziroglu ◽  
Pattraporn Sutaphakdee ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Taguchi Method ◽  
Water Content ◽  
Vinyl Acetate ◽  
Orthogonal Array ◽  
Lightweight Concrete ◽  
Plastic Waste ◽  
Ethyl Vinyl ◽  
Cement Ratio ◽  
Mix Proportion

In this study, mix proportion parameters of lightweight concrete (LWC) containing ethyl vinyl acetate (EVA) plastic waste from footwear manufacture were investigated by employing Taguchis method and ANOVA statistics. The mixtures were designed in a L9 orthogonal array with four factors viz., water/cement, water content, EVA content and sand/cement. The results showed that EVA content and water/cement ratio had the significant effect on density and compressive strength of LWC. The density and compressive strength of the LWC containing EVA waste ranged from 1172 to 1441 kg/m3 and from 3.5 to 10.8 MPa, respectively. It can be concluded that the obtained LWC can be classified as masonry concrete. The best possible levels for mix proportions were determined to optimize density and compressive strength of the samples.

Utilization of Phosphorus Slag and Fly Ash for the Preparation of Ready-Mixed Mortar

2013 ◽  
Vol 423-426 ◽  
pp. 987-992 ◽  
Author(s):  
Xiu Wei Liu ◽  
Lin Yang ◽  
Bin Zhang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Raw Materials ◽  
Setting Time ◽  
Technological Parameters ◽  
Mix Proportion ◽  
Optimal Mix ◽  
Mixed Mortar ◽  
Chinese Standard ◽  
Phosphorous Slag

Phosphorous slag and fly ash were used as raw materials for the preparation of ready-mixed mortar, and a series of technological parameters, such as phosphorus slag content, fly ash content, and chemical activators were investigated based on the compressive strength and setting time of specimens in this paper and the performances of products were also tested. The results showed that the optimal mix proportion for preparing ready-mixed mortar (M10) is as follows: cement 5%, phosphorous slag 10%, fly ash 10%, sand 75%, water reducer 1% and chemical activator 1%. The consistency, water retaining, setting time, 28d compressive strength, 14d bond strength and 28d shrinkage meet the requirement of Chinese standard GB/T 25181-2010.

scholarly journals Development of a New Type of Alkali-Free Liquid Accelerator for Wet Shotcrete in Coal Mine and Its Engineering Application

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Gang Zhou ◽  
Weimin Cheng ◽  
Sen Cao
Keyword(s):  
Compressive Strength ◽  
Raw Materials ◽  
Setting Time ◽  
Engineering Application ◽  
First Grade ◽  
Dust Concentration ◽  
National Standard ◽  
Initial Setting Time ◽  
Initial Setting ◽  
New Type

In order to address issues such as large rebound rate, high dust concentration, and low compressive strength of shotcrete when adding liquid accelerator during wet spraying, the factors influencing the efficiency of liquid accelerator were experimentally analyzed. The single-admixture, combination, and orthogonal tests were conducted on the five fundamental raw materials required to develop the new liquid accelerator. The WT-1 type liquid accelerator, which had better adaptability to different kinds of cement, was developed with the mass concentration ratio of 55% aluminum sulfate octadecahydrate, 4% sodium fluoride, 2.5% triethanolamine, 0.5% polyacrylamide, 5% bentonite, and 33% water. Experimental investigation showed that the initial setting time of the reference cement with 6% mass content of this liquid accelerator was 2 minutes and 15 seconds, and the final setting time was 7 minutes and 5 seconds. The compressive strength after 1 day of curing was 13.6 MPa and the strength ratio after 28 days of curing was 94.8%, which met the first grade product requirements of the China National Standard. Compared with the conventional type liquid accelerator, the proposed type WT-1 accelerator is capable of effectively reducing the rebound rate and dust concentration while significantly increasing the compressive strength of the shotcrete.

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