scholarly journals Temperature Field Variation Law of Low Exothermic Polymer Grouting Material in Repairing Void Damage of Frozen Soil Subgrade

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Bei Zhang ◽  
Baolin Wang ◽  
Yanhui Zhong ◽  
Shuangjie Wang ◽  
Xiaolong Li ◽  
...  
Keyword(s):  
Temperature Field ◽  
Lower Boundary ◽  
Negative Temperature ◽  
Frozen Soil ◽  
Field Variation ◽  
Monitoring Point ◽  
Curing Reaction ◽  
Grouting Material ◽  
Void Area ◽  
Peripheral Temperature

In this study, the self-developed grouting mold was used to study the heat release characteristics of different density polymer grouting material under different temperature conditions. The spatial distribution characteristics of the frozen soil subgrade temperature field under the effect of polymer grouting repair were analyzed. Further, the rules governing the temperature change of a frozen soil subgrade monitoring point under the effect of polymer grouting repair were studied. The heat transfer mechanism of polymer grouting material in frozen soil subgrade was revealed. The results showed that in the void region of the frozen soil subgrade, a discontinuity zone appeared in the temperature field distribution isotherm due to the effect of voids; this zone exhibited a layered radioactive distribution along the two sides of the void area. Furthermore, during the exothermic stage of the curing reaction, the temperature distribution isotherms changed from a layered radioactive distribution to a ring distribution that decreased from the inside to outside. During the natural cooling process, the peripheral temperature of the ring isotherm first decreased and a negative temperature ring-shaped isotherm gradually formed. Finally, the upper boundary of the influence of the heat energy released by the curing reaction on the frozen soil subgrade temperature field was determined to be 30 cm, and the lower boundary was 20 cm.

scholarly journals Experimental Study on Reducing the Heat of Curing Reaction of Polyurethane Polymer Grouting Material

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Bei Zhang ◽  
Baolin Wang ◽  
Yanhui Zhong ◽  
Shuangjie Wang ◽  
Xiaolong Li ◽  
...  
Keyword(s):  
Temperature Rise ◽  
Boiling Point ◽  
Frozen Soil ◽  
Temperature Threshold ◽  
Foaming Agent ◽  
Curing Reaction ◽  
Grouting Material ◽  
Thermal Disturbance ◽  
High Boiling Point ◽  
The Common

Polyurethane polymer grouting material has been effectively applied and promoted in the repair of road damages in nonfrozen areas. However, this material undergoes an exothermic reaction in the curing stage, which can cause a thermal disturbance in the frozen soil subgrade. To minimize the influence of the thermal disturbance of the polyurethane polymer grouting material in the repair of the frozen soil subgrade, an experiment was conducted to reduce the heat of the curing reaction under the influence of different proportions of a foaming agent, high-boiling point solvent, catalyst, and prepolymer. According to these test results, a proportioning scheme for the low exothermic polymer grouting material was formulated. The results indicated that the curing reaction temperature threshold of the polyurethane polymer grouting material was negatively related to the proportion of physical foaming agent (HCFC-141b) and high-boiling point solvent and positively related to the proportion of water weight. In the three stages of rapid temperature rise, slow temperature rise, and constant temperature, the rate of the temperature rise of the low exothermic polymer grouting material was lower than that of the common polymer, and the curing temperature threshold was 30.34% lower at a value of 101°C. At a density of 80 kg/m3, the compressive strength and tensile strength of the low heat release polymer grouting material were lower than those of the common polymer grouting material, thereby ensuring the excellent performance of polyurethane foam and providing a theoretical reference for the rapid repair of frozen soil roadbed diseases.

Heat Effect Analysis of Buried Oil Pipeline in the Qinghai-Tibet Plateau

2014 ◽  
Vol 501-504 ◽  
pp. 211-217
Author(s):  
Wei Bo Liu ◽  
Wen Bing Yu ◽  
Xin Yi ◽  
Lin Chen
Keyword(s):  
Temperature Field ◽  
Frozen Soil ◽  
Operating Conditions ◽  
Tibet Plateau ◽  
Soil Mechanic ◽  
Insulation Layer ◽  
Effect Analysis ◽  
Oil Pipeline ◽  
Permafrost Table ◽  
Qinghai Tibet Plateau

The Geermu-Lasa oil pipeline was located in the Qinghai-Tibet Plateau permafrost regions. The building and operating of pipeline will change the temperature field of soil around it, which can lead to changes of frozen soil mechanic properties, and this will induces deformation or even fracture of pipeline. These phenomena will affect the normal transportation of oil. In this paper, temperature field around the pipelines were analyzed due to different pipe diameters and different insulation layer thicknesses in the way of finite element method. The rule of thawing and freezing of soil around the pipeline in an annual cycle was obtained. Artificial permafrost table variations under the pipeline were also obtained due to different operating conditions. For 30cm diameter pipeline with 7cm insulation layer, its artificial permafrost table depth change value is just 0.48m after 30-year running. These analysis results can provide references to the construction of the new Geermu-Lasa oil pipeline.

Investigation of the Constitutive Modle of Saturated Frozen Soil Based on Damage

2013 ◽  
Vol 353-356 ◽  
pp. 221-224
Author(s):  
Shuang Zhang ◽  
Chun An Tang ◽  
Lei Li ◽  
Shuai Li
Keyword(s):  
Phase Transition ◽  
Temperature Field ◽  
Stress Field ◽  
Constitutive Model ◽  
Internal Structure ◽  
Damage Mechanics ◽  
Frozen Soil ◽  
Unfrozen Water ◽  
Freezing And Thawing ◽  
Water Field

Saturated frozen soil is composed of soil, unfrozen water and ice, whose subgrade deformation is due to the weakened of internal structure which coursed by damage of the materials in the process of the cycle of freezing and thawing. Considing of the heterogeneity of saturated frozen soil and the phase transition between water and ice, and using of the damage mechanics theory, thermodynamics theory, filtration mechanics theory, a constitutive model of saturated frozen soil is setted up, which is of the coupfing problem of temperature field, water field and stress field. The rationality and validity of the model is verified by the experiment. It is also provided a new method for the study of frozen soil.

Experimental and numerical investigation of the thermomechanical load on a turbine housing in a radial turbocharger

2021 ◽  
pp. 095440702110521
Author(s):  
Shaolin Chen ◽  
Hong Zhang ◽  
Liaoping Hu ◽  
Guangqing He ◽  
Fen Lei ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Temperature Field ◽  
Fatigue Life ◽  
Simulation Analysis ◽  
Simulation Method ◽  
Testing Temperature ◽  
Experimental Results ◽  
Maximum Temperature ◽  
Monitoring Point ◽  
Turbine Housing

The fatigue life of turbine housing is an important index to measure the reliability of a radial turbocharger. The increase in turbine inlet temperatures in the last few years has resulted in a decrease in the fatigue life of turbine housing. A simulation method and experimental verification are required to predict the life of a turbine housing in the early design and development process precisely. The temperature field distribution of the turbine housing is calculated using the steady-state bidirectional coupled conjugate heat transfer method. Next, the temperature field results are considered as the boundary for calculating the turbine housing temperature and thermomechanical strain, and then, the thermomechanical strain of the turbine housing is determined. Infrared and digital image correlations are used to measure the turbine housing surface temperature and total thermomechanical strain. Compared to the numerical solution, the maximum temperature RMS (Root Mean Square) error of the monitoring point in the monitoring area is only 3.5%; the maximum strain RMS error reached 11%. Experimental results of temperature field test and strain measurement test show that the testing temperature and total strain results are approximately equal to the solution of the numerical simulation. Based on the comparison between the numerical calculation and experimental results, the numerical simulation and test results were found to be in good agreement. The experimental and simulation results of this method can be used as the temperature and strain (stress) boundaries for subsequent thermomechanical fatigue (TMF) simulation analysis of the turbine housing.

Study of Temperature Field Distribution and Deformation of Chain Link Based on Pro/E

2014 ◽  
Vol 490-491 ◽  
pp. 836-840
Author(s):  
Bing Ma ◽  
Li Zhen Liu ◽  
Xue Feng Bai ◽  
He Wang ◽  
Li Wei Yang ◽  
...  
Keyword(s):  
Temperature Field ◽  
Thermal Conduction ◽  
Heat Recovery ◽  
Maximum Stress ◽  
Hot Forging ◽  
Field Variation ◽  
Temperature Field Distribution ◽  
Chain Link ◽  
Temperature Filed ◽  
Stress And Deformation

This paper studies the temperature field variation of the chain link as well as the stress and deformation distribution of the pin which works in hot forging and stamping production line with heat recovery function. The approach is to build the model of the chain link with Pro/Engineer and apply it to the simulation with Pro/Mechanica. To be specific, it is to stimulate the thermal conduction of the chain link and the stress state of the pin under high temperature with Pro/Mechanica-Thermal and Pro/Mechanica-Structure module, respectively. The results are the temperature filed nephogram of the chain link as well as the stress and deformation nephogram of the pin. The simulation shows that:1) the temperature reaches 420°C at the contacts of the outer and inner plates at 600s, 2) the maximum stress of the pin is 112Mpa at the ends where the pin meets the outer and inner plates,3) the pins max deformation is 0.0159mm at the middle of the pin. Comparing the simulation to the actual temperature at the contacts of the outer and inner plates,which is measured ten times in advance with average of 439°C ,the simulation is favorable. According to the results above, graphite lubrication should be chosen for the chain and the pin can work properly with deformation rate of 0.795. By this way of simulating with Pro/Mechanica, complicated calculations and repeated tests can be reduced largely, meanwhile, useful parameters and mathematical model can also be provided for manufacturing and process control.

Experimental Study of the Effect of Different Well Flow Quota on Groundwater Thermal Flow Transport Variation

2012 ◽  
Vol 204-208 ◽  
pp. 4239-4244
Author(s):  
Xue Zhi Zhou ◽  
Qing Gao ◽  
Chun Qiang Ma ◽  
Xiao Wen Zhao
Keyword(s):  
Heat Transfer ◽  
Temperature Field ◽  
Flow Rate ◽  
Cold Water ◽  
Experimental System ◽  
Energy Utilization ◽  
Field Variation ◽  
Thermal Flow ◽  
Transport Characteristic ◽  
Flow Transport

In earth energy utilization, different multi-well flow match modes determine the different groundwater thermal flow transport characteristic. In this study, a laboratory experimental system was designed and set up to study the aquifer heat transfer performance and temperature field variation in different multi-well flow match modes. The experimental results show that under the condition of certain total flow rate, different multi-well flow match modes have great effects on the change of groundwater seepage field and temperature field. The bigger the flow rate, the greater the heat transfer per unit time and temperature field variation, and the closer the occurrence time between cold water frontal and cold water effect frontal, which is not conducive to the active control of aquifer temperature field.

Analysis of Model Test Data for CFG Group Piles in Permafrost Areas

2014 ◽  
Vol 501-504 ◽  
pp. 16-19
Author(s):  
Zhao Jian Luan ◽  
Qiang Xin ◽  
Yan Min Jia
Keyword(s):  
Temperature Field ◽  
Heat Effect ◽  
Frozen Soil ◽  
Hydration Heat ◽  
Measured Temperature ◽  
Geological Conditions ◽  
Soil Temperatures ◽  
Concrete Hydration ◽  
Group Piles ◽  
Model Temperature

In this paper, the author simulates geological conditions of permafrost areas, establi-shes CFG group piles indoor model, observes the pile and frozen soil temperature field, then compares the calculated results of the group piles and frozen soil temperatures under concrete hydration heat effect by using ABAQUS with the measured temperature data, thus determines the applicability of ABAQUS for analysis of CFG group piles temperature in permafrost areas, in order to analyze temperature distribution regularities of group piles and frozen soil under concrete hydration heat effect, thermal perturbation range of CFG group piles in permafrost areas, and effects of different concrete molding temperature on model temperature field.

Sign in / Sign up

Export Citation Format

Share Document