A pasty clay–cement grouting material for soft and loose ground under groundwater conditions

In this study, three different diameters of multi-walled carbon nanotubes (MWCNTs) dispersed by polyvinyl pyrrolidone (PVP) were used to reinforce superfine cement grouting materials. The effect of MWCNTs and polyvinyl pyrrolidone (PVP) on the rheological properties of grouting material were accordingly studied. It was found that the yield stress (τ0) and plastic viscosity (η) were slightly decreased when PVP content was low and increased when the PVP content increased. The effect of MWCNT diameter on τ0 was not found to be clear but was more significant on η. The smaller MWCNT diameter was, the more quickly η increase. It was also found that the thixotropic ring area was increased as the MWCNTs content increased. The addition of PVP and MWCNTs caused an increase in the number of entanglement points in different scales, which was the main reason for the viscosity and thixotropy increase. Therefore, the rheological properties of superfine cement grouting material should be adjusted when MWCNTs were added as a reinforcing component. Due to the wrapping of PVP on cement particles which isolates the contacting part between the water and the cement particles, it slows down the cement's hydration rate thus slows down the fluidity loss of the slurry.

Download Full-text

Study on Microfine Cement Grouting Material for Silty Fine Sand Stratum

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.838-841.1457 ◽

2013 ◽

Vol 838-841 ◽

pp. 1457-1462

Author(s):

Chun Lei Xia ◽

Ying Ye ◽

Guan Ming Wang ◽

Li Cui

Keyword(s):

Portland Cement ◽

Particle Diameter ◽

Fine Sand ◽

Cement Grouting ◽

Grouting Material ◽

Soluble Glass ◽

Microfine Cement ◽

Sand Flow ◽

Sand Stratum ◽

Grouting Materials

Silty fine sand is the second smallest sand with a particle diameter ranging from 0.0625 to 0.120 mm.This kind of sand exists in a large amount in Beijing subway excavation project. Due to the poor self-stabilization of this stratum,seeping , sand flow and collapse take place frequently. Grouting materials such as Portland cement and soluble glass (also called sodium silicate) are employed in most of excavation projects to reinforce this sand stratum. However, the reinforcement is not effective, leading to a large amount of accidents in the process of construction. The reason may be attributed to the fact that Portland cement is unable to penetrate into the stratum and the strength of soluble glass (0.6MPa) is too weak to resist the stratum pressure. To solve this problem, a modified microfine cement grouting material able to penetrate into silty fine sand stratum is developed in this paper. A combination of suspension and diluent is used to increase the penetration extension of the grouts,and the experimental results reveal that the addition of the mixture of suspension and diluent in microfine cement grouting materials improves the penetration property substantially.

Download Full-text

Effects of Coal Gangue on Cement Grouting Material Properties

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/359/1/012023 ◽

2018 ◽

Vol 359 ◽

pp. 012023 ◽

Cited By ~ 1

Author(s):

J Y Liu ◽

H X Chen

Keyword(s):

Material Properties ◽

Coal Gangue ◽

Cement Grouting ◽

Grouting Material

Download Full-text

High-Fluidization, Early Strength Cement Grouting Material Enhanced by Nano-SiO2: Formula and Mechanisms

Materials ◽

10.3390/ma14206144 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6144

Author(s):

Jiaolong Ren ◽

Zedong Zhao ◽

Yinshan Xu ◽

Siyuan Wang ◽

Haiwei Chen ◽

...

Keyword(s):

Functional Requirements ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Rapid Repair ◽

Nano Sio2 ◽

Civil Infrastructures ◽

Cement Grouting ◽

Grouting Material ◽

Early Strength ◽

Grouting Materials

Cement grouting material is one of the most important materials in civil construction at present, for seepage prevention, rapid repair, and reinforcement. To achieve the ever-increasing functional requirements of civil infrastructures, cement grouting materials must have the specific performance of high fluidization, early strength, and low shrinkage. In recent years, nanomaterials have been widely used to improve the engineering performance of cement grouting materials. However, the mechanisms of nanomaterials in grouting materials are not clear. Hence, a high-fluidization, early strength cement grouting material, enhanced by nano-SiO2, is developed via the orthogonal experimental method in this study. The mechanisms of nano-SiO2 on the microstructure and hydration products of the HCGA, in the case of different curing ages and nano-SiO2 contents, are analyzed through scanning electron microscopy tests, X-ray diffraction tests, differential scanning calorimetry tests, and Fourier transform infrared spectroscopy tests.

Download Full-text

Research on Grouting Materials for Underground Construction Projects

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1036.319 ◽

2021 ◽

Vol 1036 ◽

pp. 319-326

Author(s):

Hao Ran Duan ◽

Peng Zhao ◽

Lei Qin ◽

Feng Jiao Shi

Keyword(s):

Environmental Pollution ◽

Large Scale ◽

Raw Materials ◽

Development Trend ◽

Engineering Practice ◽

Underground Engineering ◽

Chemical Grouting ◽

Cement Grouting ◽

Grouting Material ◽

Grouting Materials

The engineering practice shows that the application of grouting technology to treat underground engineering has strong applicability and is one of the most commonly used technical means at present. Based on the underground engineering, this paper introduces the research achievements of grouting materials in recent years, including cement-based grouting materials, mixed grouting materials, anti-scouring grouting materials, and ultra-fine cement grouting materials. Current demand of grouting materials in underground engineering, there exists large dosage of cement, high content, high cost, serious environmental pollution problems, such as looking for alternatives or mixed with other raw materials for preparation of cementation material become the development trend, compared with the cement grouting material, chemical grouting material with higher performance, but in smaller projects within the scope of application. How to reduce the production cost of chemical grouting materials, simplify the production process, overcome the existing toxicity, reduce environmental pollution and improve the durability of solidified body has become the bottleneck of its popularization and application. Some achievements have been made in the modification of cement or chemical materials by nanometer components, but there is still a long way to go before the large-scale application of grouting engineering.

Download Full-text