Grouting Technology Research Articles

Enhanced gas production from clayey-silt hydrate reservoirs based on near-well reservoir reconstruction using the high-pressure jet grouting technology

Over 90% of the global hydrate resource is accumulated in the fine-grained sediments with very low permeability. Gas production from the low-permeability hydrate reservoirs is significantly restricted by the effective transport of fluids into the production well. To improve gas production from the low-permeability hydrate reservoirs, the high-pressure jet grouting (HPJG) technology is first proposed that involves construction of an artificial jet grouting column (JGC) with relatively high-permeability around the production well using the cellular concrete. In this work, the main target is to investigate the feasibility of this proposed method for enhancing gas production by numerical simulation, aiming at the clayey-silt hydrate reservoirs in the Shenhu area of South China Sea. It is demonstrated that the hydrate dissociation efficiency and the gas productivity greatly improved by about 157% and 110%, respectively, by constructing an artificial JGC with radius of 0.5 m around the production well. The results suggest the proposed method is a promising strategy for enhancing gas production from the low-permeability hydrate reservoirs. This is mainly because the artificial JGC significantly promotes the advance of depressurization and the transport of gas and water within the reservoir. In addition, gas production performance of the proposed strategy mainly depends on JGC radius and JGC height, while the JGC porosity has less effect. For the specified clayey-silt hydrate reservoirs in the Shenhu area, the artificial JGC radius, height, and permeability are recommended as 0.5 m, 30 m, and 1.0 × 10 −12 m2, respectively.

Research on Grouting Materials for Underground Construction Projects

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.

Discussion on Grouting Technology in Civil Engineering Construction of House Building

Discussion on Grouting Technology in Civil Engineering Construction of House Building

Research on Control of Rib Spalling Disaster in the Three-Soft Coal Seam

Rib spalling disaster at the coal mining faces severely restricted the safe and efficient output of coal resources. In order to solve this problem, based on the analysis of the current status of rib spalling in the three-soft coal seam 1508 Working Face of Heyang Coal Mine, a mechanical model of sliding-type rib spalling was established and the main influencing factors that affect rib spalling are given. The mechanism of grouting technology to prevent and control rib spalling has been theoretically analyzed. A similarity simulation experiment is used to analyze the change law of roof stress under the condition of three-soft coal seam mining. The optimal grouting pressure is determined by a numerical simulation experiment. And, silicate-modified polymer grouting reinforcement materials (SMPGMs) are used in field experiments. After twice grouting operations in the 1508 Working Face, the coal wall was changed from the original soft and extremely easy rib spalling to a straight coal wall and the amount of rib spalling has been reduced by 57.45% and 48.43, respectively. And, the mining height has increased by 0.16 m and 0.23 m, respectively. The experimental results show that the rib spalling disaster of the three-soft coal seam has been effectively controlled.

Mechanism and Control of Cable Breakage in a Roadway with Thick Top Coal in a Rockburst Mine

Because top coal is not stable, a roadway with thick top coal often appears to mine pressure problems, such as bolt failure, cable breakage, and roof caving. In particular, these problems are more serious in rockburst mines. Based on a cable breakage case of No. 3 roadway in Xingcun coal mine, the paper analyzed the stress and elastic energy evolution law of surrounding rock and stress state of cable in the 3# roadway by means of the numerical simulation method. Thus, the cable breakage mechanism of the roadway with thick top coal in rockburst mine was revealed. Then, because surrounding rock grouting can reduce the stress concentration of surrounding rock and cable, surrounding rock grouting technology was proposed as control technology of cable breakage. Finally, parameters of surrounding rock grouting were designed and applied in the No. 3 roadway. The field results showed that surrounding rock grouting technology can be one of the solutions for cable breakage of roadway with thick top coal in rockburst mine. The research results of this paper can provide certain theoretical and practical value for mine pressure control of roadway.

Application and Development Trend of Grouting Technology in Prevention and Control of Ordovician Limestone Water Disaster in North China Type Coalfields

The hydrogeological conditions of North China type coalfields are complex. With the large-scale development of deep resources, the probability of Ordovician limestone water inrush from coal seam floor increases. Ordovician limestone water disaster has become a serious safety threat to deep mining in North China type coalfields. Since the application of grouting technology can quickly block the water inrush passage and eliminate potential floods, it has obvious advantages in the prevention and control of Ordovician limestone water disasters in North China type coalfields. Equipment progresses, such as working face grouting, downhole directional drilling grouting and surface directional drilling grouting, promote the sustainable development of grouting technology for prevention and control of Ordovician limestone water disaster in North China type coalfields. This paper analyzed the development process of grouting technology in the prevention and control of Ordovician limestone water disaster in North China type coalfields, analyzed the problems encountered for surface directional drilling grouting in practice based on advanced Ordovician limestone water disaster treatment project cases, and pointed out the development direction of surface directional drilling grouting technology for regional water disaster prevention and control. This paper is of important reference significance for prevention and control of Ordovician limestone water disaster in deep mining floor of North China type coalfields.

Numerical investigation of flow control technology for grouting and blocking of flowing water in karst conduits

AbstractA sequential flow and solidification method was applied to the numerical investigation of flow control technology for grouting and blocking of flowing water in karst conduits. This method accounted for the temporal‐ and spatial‐evolution characteristics of the viscosity. It achieved the visualization of grouting in flowing water in a conduit, and was used to explore a reasonable and effective method for grouting through flow‐control technology. Firstly, the responses of different water tables and flow‐control intensities were studied by establishing a generalized model of flow control at the outlet of a conduit. Secondly, the initial sedimentation location and the distance of down‐flow and counter‐flow of slurries with different intensities of flow control were compared and analyzed. The outlet flow, the loss rate of the slurry, and the distribution laws of velocity and pressure inside the conduit during plugging were further analyzed. In addition, the mechanism of flow control for the grouting and plugging of large‐flow conduits was revealed. The results showed that the most direct effect of flow control on grouting was to decrease the flow rate of flowing water, and the most essential role was to improve the retention rate of slurry. Moreover, the results were applied to the large‐scale water inrush control project of Hejing Limestone Mine, China. The slurry stop devices improved the retention rate of slurry and optimized the grouting technology, which had a certain guiding significance in the treatment of water‐inrush disasters in karst areas.

Seepage in Water-Rich Loess Tunnel Excavating Process and Grouting Control Effect

The tunnel passing through the loess stratum with high moisture content can easily lead to the seepage and mud burst accident and the instability and collapse of the tunnel face. Under the condition of high groundwater level, the seepage situation is more complicated, it is difficult to control the groundwater seepage, and the excavation progress is very slow. In order to solve the various disasters when the tunnel passes through the water-rich loess stratum, taking a water-rich loess tunnel in Gansu Province as an example, the method of comprehensive prevention and control of seepage and mud inrushing disaster by basement grouting and curtain grouting was introduced. Firstly, the basic situation of the Yulinzi tunnel is introduced, including site conditions, seepage collapse accident, and its cause analysis. On this basis, the design and construction methods of basement grouting and curtain grouting are introduced, and the effect of grouting reinforcement is evaluated in detail through on-site monitoring. The results show that the basement grouting and curtain grouting can effectively control the deformation of surrounding rock and the surface settlement, the decrease of the deformation of surrounding rock can reach 36%-71%, and the decrease of the surface settlement can reach 55%. After grouting, the deformation of the surface and surrounding rock can be controlled within the allowable value in the code. Grouting plus solid can effectively block the seepage of groundwater and prevent the surface cracks, water gushing, mud gushing, collapse, and other disasters in the process of tunnel excavation. It can be seen that the basement grouting combined with curtain grouting technology has a good reinforcement effect, which has significant engineering value for quickly and efficiently passing through high moisture content loess strata.

Quality evaluation method of water isolating curtain in roadway of Gushan Iron Mine and its application

In water-rich metal mines, the roadway can encounter various water inrush risks in the process of excavation, in which case the advanced curtain grouting technology should be carried out to isolate water and ensure the safety of driving. In view of the inadequacy of the quality evaluation system of water isolating curtain in the roadway, a new evaluation method with three evaluation indexes was proposed. In order to study the pre-evaluation index “Minimum effective thickness,” the pore water pressure field, stress field, and plastic zone of surrounding rock were calculated under different conditions of curtain thickness based on the fluid–structure interaction theory by COMSOL Multiphysics. It can be concluded that the “Minimum effective thickness” of water isolating curtain in Gushan Iron Mine is 2.5 m. Then, “Ratio of curtain to grout in roadway” and “Double value of roadway” were proposed to be the post-evaluation indexes of water isolating curtain. At the same time, their calculation formulas were put forward based on the firsthand data recorded in the construction field. Finally, this new evaluation method was applied to the curtain grouting section of −300 m level roadway in Gushan Iron Mine, which can provide a reference for similar underground engineering applications.

Discussion on grouting construction method and technology in civil engineering

With the rapid economic development in recent years, the development of civil engineering has become more and more rapid. Therefore, in order to ensure the quality of civil engineering construction, it is necessary to reasonably modify the grouting construction method of civil engineering construction. By improving the grouting construction method, the quality of civil engineering can be guaranteed as much as possible. Therefore, this article mainly analyses and discusses the application of grouting technology in civil engineering construction. Through the analysis of the importance of grouting technology in civil engineering construction, we can further enhance the construction unit’s attention to grouting technology and promote the effective development of grouting construction technology in civil engineering.

Unsteady Approximate Model of Grouting in Fractured Channels Based on Bingham Fluid

It is of great significance for the improvement of grouting technology and engineering practice to master the flow law of grout between parallel plates. However, the traditional calculation model ignores the influence of the inertia term and only considers the stable flow of slurry, so there is a big error in some cases. It is difficult to solve the motion equation of a Bingham fluid considering the inertial force term directly. Combined with the relationship between the steady-state flow equation of a Bingham fluid and a Newtonian fluid, the approximate unsteady-state flow equation of a Bingham fluid suitable for describing slurry flow is constructed. In addition, according to the unsteady flow equation, the relationship between the time and distance of slurry flow in parallel plate fractures can be obtained, and the simplified conditions of the Bingham fluid unsteady flow model are given. Finally, the accuracy of the flow equations and the simplified conditions are verified by experiments and numerical calculations.

Research on Grouting Construction of Icebreaking Cone Structure of Single Pile in Dalian Offshore Wind Power Project

Introduction The icebreaking cone structure is a unique structure of the offshore wind power single pile foundation structure in north. The installation of the icebreaking cone is one of the key points and difficulties in the construction of the single pile foundation. The grouting connection technology solves this problem through assembled construction successfully. For the first time in China， a single pile icebreaking cone structure is used in an offshore wind power project in Dalian. Method Supported by the engineering practice of the project’s icebreaking cone grouting construction he critical technique of single pile icebreaking cone grounding construction was studied including installation preparation， grouting material selection， grouting pipeline design and optimization， grouting plugging and grouting construction quality control etc. Result In this study， by using Ugrount® SKG-V， self-developed high-strength grouting material， the small-scale containerized integrated marine wind power grouting equipment and the self-developed underwater grouting technology， the material and construction performance had met the requirements， and the grouting connection between single pile icebreaking cone structure and single pile was successfully completed for the first time. Conclusion This material and technology are expected to be widely applied in the single pile foundation structure of offshore wind power in northern China.

Bond Behavior between Concrete and Self-Expansion Polymer Material under Normal Pressures

Self-expansion polymer grouting technology is a new rapid trenchless method for repairing leakage and subsidence of underground concrete structures. The bond between polymer and concrete is critical to determine the ultimate conditions of repaired concrete. In this paper, a series of direct shear tests were performed to investigate the influence of normal pressure on the shear bond properties between self-expansion polymer and concrete with different polymer density and concrete strength. Results indicate that failure modes and bond strength are greatly influenced by the normal pressure for specimens with a lower polymer density. For a given normal pressure, the bond strength linearly increases with the increasing polymer density. As the polymer density increased up to 0.43 g/cm3, the increased ratio decreases with the polymer density. Moreover, the displacement at the peak point reduces with an increase in polymer density. Finally, a finite element model is proposed to evaluate the bond strength for specimen failure in concrete and verified with the test results.

A Numerical Simulation of Bolt Grouting Reinforcement for Reducing the Optimum Dimensions of Jointed Hard Rock Pillars in Faryab Chromite Mine (Iran)

The maintaining needed for underground mining operations is satisfied by installing a support system or leaving an ore pillars. These pillars need to have enough stability to bearing the overburden loading. Designing a pillar with optimum dimensions is the most significant issues in room and pillars underground mining method. The purpose of this paper is to determine the optimum dimensions of rock pillars in Faryab mine and reducing their dimensions using grouting technology based on a numerical simulation. The modeling results, before grouting operation, show that in the area where the pillars height is 12 m, the pillars with a width of 8 m are stable and the pillars with a width of 7 m are unstable and are on the verge of destruction. So a pillar with a width of 7 m is considered in order to stabilization. 2D and 3D numerical modeling results show that using bolt grouting in jointed rocks, improved the strength properties and as a result increase the strength of pillars and make it completely stable. Accordingly, in the rock masses that can be injected, the grouting operation can reduce the pillars width and increase the extraction recovery.

Theoretical Research and Numerical Simulation on Water Resistance Mechanism of Textile Bag in Water Passage

It is an important problem in the mine water disaster prevention and control to control the large passage moving water. Traditional grouting technology is to put coarse aggregate and fine aggregate downward first and then grouting treatment. But the aggregate and cement flow distance is long, consumption is large, cost is high, and easy to appear secondary water inrush. Centering on the technical difficulties in the rapid construction of the blocking body of the moving water passage, a water-blocking textile bag was invented. The purpose of blocking the tunnel water inrush was achieved by grouting inside the bag body, which fundamentally realized the rapid blocking of the large passage through water under the condition of moving water. However, the mechanism, water plugging law, and design parameters of water blocking roadway with textile bag are still unclear. In this paper, the slip law and stability of the textile bag in the moving water and the deformation characteristics caused by the dynamic water pressure are theoretically analyzed and simulated. Through theoretical analysis, the ultimate antihydraulic stress value of a textile bag of a certain specification is calculated, and the parameters of the textile bag that affect the stability of the bag body are also determined. Xflow was used for numerical simulation analysis to study the deformation characteristics of the textile bag under water and the law of water barrier. The simulation analysis focuses on the water resistance effect and flow field distribution characteristics of the textile bag in the water passage under the condition of low flow rate and low pressure, as well as the stability and self-deformation characteristics of the textile bag under the condition of high flow rate and high pressure. The accuracy of the limit resistance to water pressure of the textile bag obtained from theoretical analysis is verified. The results show that the theoretical analysis is consistent with the simulation results. The textile bag can realize the fast controllable plugging of the large water passage of moving water within the limit of the antihydraulic stress.

Mechanical Characteristic Analysis of Buried Drainage Pipes after Polymer Grouting Trenchless Rehabilitation

The application of polymer grouting in underground pipeline rehabilitation is increasing gradually. The leakage and subsidence of buried pipelines could be repaired by polymer grouting technology. In order to analyse the calculation theory of the pipeline repairing process, the Winkler model and the Vlazov model of the pipe-soil-polymer interaction based on the elastoplastic theory are established, the calculation formulas of the pipe-soil interaction under polymer grouting are derived, and the MATLAB calculation program based on the transfer matrix method is compiled. Then the calculated values are compared with the pipeline experimental values, and the influence of different factors on the internal force and deformation of the polymer-repaired pipeline under different work conditions is discussed. The results show that the values and trends of the pipe deformation and circumferential bending moment calculated by the models are consistent with the experimental results, and the results obtained by the Vlazov model are closer to the experimental values. In addition, the void at the bottom of the pipeline has a large impact on the mechanical properties of the pipeline. However, polymer grouting can repair disengaged pipelines effectively and restore their mechanical properties. The proposed methods and calculation results are valuable for pipeline polymer repairing analysis and pipeline void repairing design.

Grouting Mechanism in Water-Bearing Fractured Rock Based on Two-Phase Flow

Grouting is always used in mine water plugging, reinforcement, and other disaster prevention projects. The diffusion mechanism of slurry in fractured rock is affected by geological environment and slurry performance, which should be revealed and characterized better. Based on the two-phase flow diffusion theory, a slurry diffusion model considering flowing water condition was established for a blocking area of a fracture zone in one case from China. The feasibility of two-phase flow model in grouting diffusion calculation was analyzed. The diffusion model in dynamic water environment was studied, and the diffusion range varying with time in the grouting area of Zhangji Coal Mine was explored. The optimization method of multi grouting holes was put forward, and the influence of water flowing was discussed. The results show that the slurry diffusion calculated by the two-phase flow model was feasible and consistent with the experimental study. The dynamic water can change the conventional circular diffusion state of slurry, but its pattern was oval and leaf type. There were different penetration distances in directions, and typical grouting voids were made on the side and upstream. When the single-hole grouting was carried out, the predetermined value can be achieved in the height range, but it was only about 15 m on the side because of the water flowing, which cannot meet the requirements. The optimization scheme of grouting was put forward, which adopted multiple grouting holes in the long side, and grouting in different directions and periods to avoid the possible problems of multihole intersection. The rationality and effectiveness of the proposed optimization method were verified through the calculation of water yield and analysis of cement composition from the drilling core in the grouted zone. In the grouting process, the water flowing has double effects, which has a significant role in promoting and scouring along the flow direction, but there is a significant weakness in the side diffusion. It is very important to realize the rational use of the dynamic water through the optimization scheme. This study is an important basic work of grouting mechanism, and it is expected to promote the development of grouting technology and application of two-phase fluid-solid coupling theory.

Study on dynamic viscoelastic properties and constitutive model of non-water reacted polyurethane grouting materials

Polyurethane grouting materials are new repairing and impermeable materials for infrastures especilly in rush to repair. Aiming at dynamic viscoelastic properties of the new-type mateials, firstly, the dynamic viscoelastic properties of polyurethane grouting materials was studied by Dynamic Mechanical Thermal Analysis. Then the influential factors for these properties were studied and the mechanism behind their changes were analysed from a microscopic perspective. In addition, the high and low temperature performance and application areas of polymer materials were also studied for their application region. Then, a viscoelastic constitutive model of new-type mateials based on the generalised Maxwell model (GMM) was established for further dynamic structure analysis and the model was verified by a dynamic centrifuge test. Furthermore, the accuracy of the model was compared with that of a linear elastic model. The results of this study provide a scientific basis for the application and development of polyurethane grouting technology for applications.

Application and Analysis of Curtain Grouting in Seepage Prevention and Reinforcement of Masonry Dam

At present, the number of masonry dam in China is still relatively large. Due to various reasons, many of the dam body appears aging, degradation and other phenomena, and leakage is one of the common problems. Now grouting technology is the main technical means of anti-seepage treatment. Curtain grouting technology has wide adaptability to strata. With the gradual improvement of grouting technology, it has been widely applied in engineering and water conservancy projects. In order to ensure the safety of the dam and improve the grouting effect, this paper summarizes the rules of anti-seepage treatment based on the actual grouting treatment methods, and provides technical guidance for the anti-seepage treatment of other similar masonry dams.

基于注浆技术的沥青路面病害综合处治方法研究

基于注浆技术的沥青路面病害综合处治方法研究