Study On Ventilation And Dust Removal Technology And Optimization Of Single Channel Cavern Group Construction

With the continuous development of tunnel engineering in China,the construction of urban underground caverns has become more and more common.The number of operating personnel required for underground caverns construction is much higher than that of traditional single tunnel,and the construction environment becomes more complicated.In order to ensure the normal construction work and the physical and mental health of the construction personnel in the tunnel group,and provide a good construction environment,it is very important to ventilate and reduce dust problem of the underground caverns.In the case of construction work,the tunnel ventilation system is also an important guarantee for maintaining the normal operation of various mechanical facilities in the tunnel.And for the construction of complex large underground cavern group construction,the construction ventilation system is often the entire cavern group construction progress and construction organization design plays a crucial impact.This chapter relies on the numerical simulation of the discrete phase model by using fluent fluid software to analyze the numerical simulation of the project.Based on the actual monitoring and measurement data,the distribution size and regularity of the airflow field in the caverns of the caverns during the ventilation process are analyzed,and the distribution of the dust in the caverns is analyzed.The dust is different in the caverns And then put forward the reasonable optimization scheme of the ventilation shaft,and the following results are obtained:1.Through the study of the theoretical mechanism of ventilation and dust removal during the construction of the cavern group,the types of ventilation and the influencing factors of the dust in the construction are analyzed,and the air demand of the single hole in the 7th hole is determined.2.From the site of the measured data can be seen,the cavern group construction operations,the resulting dust will be through the channel to the adjacent channel flow,the other chamber caused secondary pollution,thus affecting the normal construction of other caverns;The dust concentration is basically the highest in the next step,the work surface but relatively low,the other area from the face of the farther away,the lower the concentration of dust distribution law;in the construction process of dust concentration are mostly exceeded,the construction staff Physical health caused serious harm,it is necessary to take reliable measures to reduce the dust concentration in order to carry out normal operations to ensure the progress of construction.3.The velocity distribution of the wind flow in the cavity is obtained by numerical analysis of the physical model by fluent software.It can be seen that the wind velocity is more obvious when the wind flow field is more than a certain distance from the working face when the tunnel is ventilated.4.The numerical simulation of the distribution of dust flow in the caverns of the 7th chamber face shows that the dust concentration near the working face is relatively low,and the farther away from the working face,the higher the dust concentration and the The allowable value,consistent with the test data values;ventilation alone can not meet the ventilation requirements of the chamber group.5.After the optimization of the shaft is added to the model,it can be seen that the operation environment of the most of the area in the cave of the silo is obviously improved,and the pollutants such as dust and dust are reduced by the shaft.Most of the areas can be normal construction,To meet the safety construction standards.