scholarly journals Laboratory Study on the Effect of Water-Cement Ratio on Strength Characteristics of Jet Grouting Columns

2021 ◽  
Vol 27 (12) ◽  
pp. 33-49
Author(s):  
Fadhil W. AL-Malkee ◽  
Mahmood D. Ahmed
Keyword(s):  
Water Flow Rate ◽  
Soil Improvement ◽  
Dry Density ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Soil Cement ◽  
Jet Grouting ◽  
Water To Cement Ratio ◽  
Geotechnical Problems ◽  
Physical And Mechanical Characteristics

Jet grouting is one of the most widely applied soil improvement techniques. It is suitable for most geotechnical problems, including improving bearing capacity, decreasing settlement, forming seals, and stabilizing slopes. One of the difficulties faced by designers is determining the strength and geometry of elements created using this method. Jet grouted soil-cement columns in soil are a complicated issue because they are dependent on a number of parameters such as soil type, grout and water flow rate, rotation and lifting speed of monitor, nozzle jetting force, and water to cement ratio of slurry. This paper discusses the effect of the water-cement ratio on the physical and mechanical characteristics of soilcrete. In the laboratory, sandy soil mixed with cement grout with water-cement ratio varies from (0.7:1 to 1.4:1). To evaluate the characteristics of soilcrete, 96 specimens were prepared in the laboratory and tested at different curing times. The results indicate that the Uniaxial Compressive Strength (UCS) of soilcrete decreases with increasing the (W/C) ratio of the grout, where the soilcrete strength of W/C ratio of 0.7 is higher about 237% of W/C ratio of 1.4 at 28-day; the evolution of the (UCS) is proportional to the logarithm of the curing time; the ratio between the modulus of elasticity (Etg50) to the maximum UCS varies from 113 to 175; when the water-cement ratio increases, the dry density of soilcrete decreases, as a result, the (USC) of soilcrete decreases.

scholarly journals An Experimental Study on Unconfined Compressive Strength of Soft Soil-Cement Mixtures with or without GGBFS in the Coastal Area of Vietnam

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Son Bui Truong ◽  
Nu Nguyen Thi ◽  
Duong Nguyen Thanh
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Unconfined Compressive Strength ◽  
Soft Soil ◽  
Soil Improvement ◽  
Treated Soil ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Granulated Blast Furnace Slag ◽  
Soil Cement

Soft soil is widely distributed in Vietnam, especially in the coastal area. In engineering practice, soft soil cannot be used to build any construction and needs to be improved or treated before building construction. In addition, Vietnam has many pig-iron or thermal power plants, which annually produce a huge amount of granulated blast furnace slag (GBFS). Thus, the use of this material for soft soil improvement needs to be considered. This paper presents experimental results on the unconfined compressive strength (UCS) of three Vietnam’s soft soils treated with Portland cement and Portland cement with ground granulated blast furnace slag (GGBFS). Binder dosage used in this study is 250, 300, and 350 kg/m3 with the three different water/cement ratios of 0.8, 0.9, and 1.0, respectively. The research results showed that the UCS of soil-cement mixtures depends on soil type, water/cement ratio, cement type, and binder content. Accordingly, the unconfined compressive strength increased with the increase of binder contents, the decrease of the natural water content of soft soil, water/cement ratios, and clay content. The highest value of UCS of treated soils was found for the soil at Site II with the Portland cement content, cement GGBFS, and water/cement ratio of 873 kg/m3, 2355 kg/m3, and 0.8, respectively. Besides, for all the three soils and two binder types, the water/cement ratio of 0.8 was found to be suitable to reach the highest UCS values of treated soil. The research results also showed that the UCS of treated soil with cement GGBFS was higher than that of treated soil with Portland cement. This indicated the effectiveness of the use of Portland cement with GGBFS in soft soil improvement. There is great potential for reducing the environmental problems regarding the waste materials from pig-iron plants in Vietnam and the construction cost as well.

scholarly journals Effect of Phenolic Particles on Mechanical and Thermal Conductivity of Foamed Sulphoaluminate Cement-Based Materials

Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3596 ◽  
Author(s):  
Xiuzhi Zhang ◽  
Qing Yang ◽  
Qinfei Li ◽  
Heng Chen ◽  
Guofa Zheng ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Pore Structure ◽  
Dry Density ◽  
Mechanical And Thermal Properties ◽  
Foaming Agent ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Performance Indexes ◽  
Foamed Concrete ◽  
Inorganic Matrix

Foamed concrete materials based on sulpoaluminate cement were prepared by the chemical foaming method. The effects of water–cement ratio, foaming agent, and foaming stabilizer on the mechanical and thermal properties of foamed concrete were studied. Meanwhile, a portion of cement was replaced with foamed phenolic particles to further optimize the performance of foamed concrete; the results show that when the water–cement ratio was 0.53, the foaming agent content was 5%, the foam stabilizer was 1%, and the substitution of phenolic particles was 20%, the performance indexes of foamed concrete were the best. Methods, describing briefly the main methods or treatments applied: dry density was 278.4 kg/m3, water absorption was 19.9%, compressive strength was 3.01 MPa, and thermal conductivity was 0.072 W/(m·K). By the pore structure analysis of the foamed concrete suing Micro-CT, it was found that when the replacement amount of phenolic particles was 20%, the pore size of foamed concrete was relatively uniform, the minimum D90 was 225 μm respectively. The combination of organic and inorganic matrix and optimized pore structure improved the performance of foamed concrete.

Effect of Water Reducer and Cellulose Ether on Sulphoaluminate Cement-Based Lightweight Thermal Insulation Board

2014 ◽  
Vol 541-542 ◽  
pp. 273-276
Author(s):  
Xiao Nan Dong ◽  
Xi Chen ◽  
Ling Chao Lu ◽  
Shuai Yang
Keyword(s):  
Mechanical Strength ◽  
Thermal Insulation ◽  
Influential Factor ◽  
Cellulose Ether ◽  
Dry Density ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Sulphoaluminate Cement ◽  
Effect Of Water ◽  
Good Workability

The effects of two admixtures content i.e. water reducer, cellulose ether and water-cement ratio on mechanical strength and dry density of cement-based lightweight thermal insulation board are studied. The result indicates that the water-cement ratio is the important influential factor, which is easier to get good workability. And based on the mechanical strength and dry density, the best range of water reducer content and cellulose ether content are 0.3%-0.6% and 0.4%-0.6% respectively.

Preparation and Performance Testing of Foamed Concrete

2013 ◽  
Vol 743-744 ◽  
pp. 166-170
Author(s):  
Ting Song Yang ◽  
Ling Chao Lu ◽  
Shou De Wang ◽  
Chen Chen Gong
Keyword(s):  
Compressive Strength ◽  
Mixing Time ◽  
Performance Testing ◽  
Dry Density ◽  
Preparation Technology ◽  
Foaming Agent ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Foamed Concrete ◽  
And Performance

The key influences of foamed concrete and the optimum preparation technology were studied. The performance of foamed concrete was analyzed by the compressive strength testing, SEM. Results show that the flowability of cement paste is good when water-cement ratio is 0.4. The amount of foam added in sulphoaluminate cement is not able to exceed 3.5L/kg. However, the dilution multiple of foaming agent is near concentration and the mixing time depends on the foam quantity. When the water-cement ratio is 0.4, the foam quantity is 3 L/kg and the foaming agent is diluted 30 times. When the mixing time is 60s, the dry density is around 380kg/m3 and the 7d compressive strength reaches to 0.9MPa.

Study on the Physical and Mechanical Performance of Graphite Foamed Cement-Based Material

2015 ◽  
Vol 1089 ◽  
pp. 265-269 ◽  
Author(s):  
Jun Liu ◽  
Xiang Mei Meng ◽  
Hong Tao Mu
Keyword(s):  
Hydrogen Peroxide ◽  
Compressive Strength ◽  
Mechanical Performance ◽  
Sodium Sulfite ◽  
Orthogonal Test ◽  
Dry Density ◽  
Foam Concrete ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Influence Of Water

To figure out the physical and mechanical performance of graphite foam concrete，orthogonal test was applied to ascertain four factors for graphite foamed cement-based material (GFCBM). The influence of water cement ratio, graphite content, hydrogen peroxide content and sodium sulfite content on the dry density, porosity and compressive strength was also discussed. The results show that sodium sulfite has a relatively significant effect on the physical and mechanical performance. The dry density and compressive strength increases first and then decrease with the water cement ratio, adding of hydrogen peroxide and sodium sulfite increasing and increase with adding of the graphite. The trend of porosity is opposite to the dry density and compressive strength. The optimal scheme for this experiment is water cement ratio 0.68, 5% graphite, 8% hydrogen peroxide and 6% sodium sulfate.

scholarly journals Response Surfaces for Fresh and Hardened Properties of Concrete with E-Waste (HIPS)

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
K. Senthil Kumar ◽  
K. Baskar
Keyword(s):  
Response Surface ◽  
Coarse Aggregate ◽  
Response Surfaces ◽  
Partial Replacement ◽  
Contour Plot ◽  
Dry Density ◽  
Waste Plastic ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Hardened Properties

The fresh and hardened properties of concrete with E-waste plastic, that is, high impact polystyrene (HIPS), as a partial replacement for coarse aggregate were analyzed using response surface methodology (RSM). Face-centred central composite response surface design was used in this study. The statistical models were developed between the factors (HIPS and water cement ratio) and their response variables (slump, fresh density, dry density, compressive strength, spilt tensile strength, and flexural strength). The Design-Expert 9.0.3 software package was used to analyze the experimental values. The relationships were established and final mathematical models in terms of coded factors from predicted responses were developed. The effects of factors on properties for all variables were seen visually from the response surface and contour plot. Validation of experiments has shown that the experimental value closely agreed with the predicted value, which validates the calculated response surface models with desirability = 1. The HIPS replacement influenced all the properties of concrete than water cement ratio. Even though all properties show the decline trend, the experimented values and predicted values give a hope that the E-waste plastic (HIPS) can be used as coarse aggregate up to certain percentage of replacement in concrete which successively reduces the hazardous solid waste problem and conserves the natural resources from exhaustion.

scholarly journals Layered Grouting Technology Based on a Comprehensive Water-to-Cement Ratio for the Overlying Loess Stratum of Urban Shallow Tunnels

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Teng Yang ◽  
Jiaqi Zhang ◽  
Xiao Zhang ◽  
Qingsong Zhang ◽  
Zhanchao Yin
Keyword(s):  
Compressive Strength ◽  
Moisture Content ◽  
Strain Curve ◽  
Test System ◽  
Engineering Properties ◽  
Dry Density ◽  
Road Tunnel ◽  
Cement Ratio ◽  
Grouting Pressure ◽  
Water To Cement Ratio

Different from sand and clay, loess has special engineering properties; hence, existing soil grouting theories are not suitable for the disaster treatment of shallow loess tunnels. In this study, a fine grouting reinforcement test system was developed, and the Yuhan Road tunnel overlying loess was used as the injection medium. An orthogonal test based on slurry dry density, moisture content, water-to-cement ratio, and grouting pressure was conducted. Results revealed that the loess samples have high integrity after grouting, and the cohesion and compressive strength improved significantly. The stress-strain curve showed that the strengthened samples have greater ultimate and residual strengths than samples before grouting. Through a range analysis, it was determined that water-to-cement ratio and moisture content are the main factors affecting loess cohesion and compressive strength. Therefore, a comprehensive test of the water-to-cement ratio and moisture content as a single variable was conducted. It was found that their influence on loess cohesion and compressive strength is not a single linear relationship but a combined balance. To characterize the joint effect of water in loess and in slurry on reinforcement, the concept of a comprehensive water-to-cement ratio is proposed, and the cohesion and compressive strength curves with respect to this ratio were drawn. An optimal comprehensive water-to-cement ratio, which corresponds to the maximum cohesion or compressive strength, was found. Based on this ratio, we further propose a method to calculate the water-to-cement ratio of slurry and suitable grouting amount for the Yuhan Road tunnel reinforcement project, in which all solution parameters can be measured via field tests. In the project, a surface layered grouting scheme, based on the optimal comprehensive water-to-cement ratio, was designed. After grouting, loess strength was improved significantly, permeability was reduced greatly, and the overall reinforcement effect was suitable; these results provide a reference for similar projects.

scholarly journals Comparison of Single and Group Jet Grouting Columns Capacity Based on Field Load Test and Theoretical Methods

2019 ◽  
Vol 5 (6) ◽  
pp. 1353-1366
Author(s):  
Ali M. Al-Kinani ◽  
Mahmood D. Ahmed
Keyword(s):  
Bearing Capacity ◽  
Soft Soil ◽  
Water Flow Rate ◽  
Theoretical Method ◽  
Load Test ◽  
Theoretical Methods ◽  
Axial Capacity ◽  
Soil Cement ◽  
Jet Grouting ◽  
Pile Load Test

The evaluation of axial capacity of jet grouted soil cement columns in soft soil is a complicated issue because it depends according to the number of factors such as, soil type, influence mixture between soil and grouting materials, nozzle jet energy, jet grouting and water flow rate, rotation and lifting speed. These parameters related to the type of jet grouting methods (single, double and triple system). Most methods of design the bearing capacity of the jet-grouting column based on experience. Therefore, some designer calculates the bearing capacity of the jet grouting column based on jet grout section capacity. In this paper, different theoretical methods have been used to estimate of the jet grouting soil-cement capacity, such as Poulos and Davis, 1980 methods and then their comparison with the pile load test calculations based on the quick pile load test as presented in ASTM-D1143-07.  Therefore, the study describes a prototype test single and group jet grout soil-cement models of arrangement (1*1, 1*2 and 2*2) for total length to diameter ratios (L/D) is 13.33 and clear spacing three times of diameter has been constructed in soft clayey soils in the right bank of the Euphrates River, at Al- Nasiriyah city. As a result, the theoretical method for estimation the bearing capacity gives unfaithful values for the single and group jet grout column compared to the load- settlement calculations obtained from field pile load test data. On the other hand, the Hansen’s 90% and Butler and Hoy’s given closer results to each other and may be considered faithful interpretation methods to compute the bearing capacity of single and group jet grouting columns.

scholarly journals Investigations on Improving the Compressive Strength of Sand Column with Cement Grout and Chemical Admixture

2021 ◽  
Vol 12 (2) ◽  
pp. 1841-1847
Author(s):  
M. Samuel Thanaraj, Et. al.
Keyword(s):  
Compressive Strength ◽  
Internal Friction ◽  
Water Content ◽  
Soil Improvement ◽  
Cement Grout ◽  
Sand Column ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Angle Of Internal Friction ◽  
Chemical Admixture

Grouting is one of the most commonly adopted technique for soil improvement and strengthening. Adding super plasticizers, accelerators, antifreezes, air entraining agent improves the performance of the cement grout. The performance of the grout while injecting in the sand column mainly depends on its fluidity property.  Keeping it in mind about the water cement ratio, the strength of the sand column is studied in two sets of experiments one by sand column with cement grout only and another set by sand column with cement grout added with super plasticizers by varying the water cement ratios. Strength parameters like angle of internal friction and cohesion were obtained be direct shear test and unconfined compressive strength test on the specimens by varying the water content. An increase of 15.2kPa to 60.33 kPa was observed in the cohesion value for specimens with 10% water content and 13.8 kpa to 47.2kPa cohesion value observed in the specimens with 20% water content. The angle of internal friction was decreased from 360 to 160 for 10% water content whereas 300 to 100 for 20% water content.  A series of experiments were conducted on the sand column grouted with cement and for different water cement ratios as 1.5, 2.0 and 2.5. Another set of experiments were repeated by adding 2%super plasticizer Sulphonated Melamine Formaldehyde (SMF). The experiment results revealed that at lower water cement ratio higher value of compressive strength was observed. It was also observed that the strength increases with curing period. 

scholarly journals Improving the safety of railway subgrade when it is strengthened using soil-cement elements

2019 ◽  
Vol 294 ◽  
pp. 03006
Author(s):  
Vitalii Krysan ◽  
Volodymyr Krysan ◽  
Volodymyr Petrenko ◽  
Oleksii Tiutkin ◽  
Volodymyr Andrieiev
Keyword(s):  
Cement Content ◽  
Laboratory Studies ◽  
Weak Soil ◽  
Civil Structures ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Soil Cement ◽  
Access Road ◽  
The Difference

The article identifies the main parameters of the drilling-mixing technology, which is the most effective in fixing weak soil bases during the construction and restoration of transport, industrial and civil structures. The difference of the technology developed by the authors is that the strengthening process is carried out at low pressure (0.15 ... 0.25 MPa). The relevance of the research is that the proposed technology requires less cost with high rates of restoring the strength of soil foundations. To prove the high quality of the technology, laboratory studies were carried out to determine the optimal characteristics of the soil-cement element, as well as the proportions and composition of the fixing solution. The dependences of the strength of soil-cement elements in the air-dry condition with cement content from 7% to 23% with water-cement ratio in solution 1 / 0.3 and with cement content from 13% to 37.5% with water-cement ratio in solution 1/0,6. During the experimental-industrial studies of the author’s technology, the embankment was constructed with the soil-cement-reinforced elements for the access road approaches at one of the facilities in Kirovograd region, which ensured safety in the operation of a complex transport structure.

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