Study On Construction Technology To Soft Surrounding Rock Highway Tunnels Mechanized Drill-blasting

With the rapid development of highway traffic construction in China,the construction of highway tunnels is booming.However,the construction of soft surrounding rock and highway tunnel is still constructed by artificial drill-blasting method.It completes by using a lot of artificial that equip the simple equipment.In order to improve the construction efficiency and promote the technical level,it is necessary to study the equipment and technologies that are suitable for the mechanized drilling and blasting methods of the soft surrounding rock tunnels.Firstly,the current construction state of highway tunnel in domestic is analyzed.Analysis the reasons and technical difficulties that the tunnels in soft surrounding rock use artificial drill-blasting method instead of mechanized drilling and blasting.Then,according to the construction difficulties that develop the mechanized drilling and blasting in the soft surrounding rock tunnel,a corresponding construction scheme was researched and proposed.And the application research was carried out in the based on project tunnel.That is,combined operation jumbo matching the vertical arch trolley can realize the mechanized drilling and blasting construction in the weak surrounding rock tunnel.Based on the follow-up investigation of the actual situation,it is found that jumbo matching the vertical arch trolley can realize the mechanized drilling and blasting method in the soft surrounding rock tunnel.Finally,combined with the actual situation of based on project and the construction characteristics of the soft surrounding rock tunnel,an evaluation system was established.In addition,the comparative evaluation of three construction schemes of soft surrounding rock highway tunnel was conducted.The evaluation system was established in terms of construction progress,quality and cost.The results show that in the construction progress,jumbo matching the vertical arch trolley has a significant improvement than that of artificial drill-blasting method.And the construction progress of the mechanized drill-blasting using the double-jumbo matching vertical arch trolley is the fastest.In terms of construction quality,the two construction methods accord with the code requirements.In addition,the mechanized construction of explosion using jumbo matching the vertical arch trolley has better control effect on over-break,which improves the quality of tunnel construction.In terms of construction cost,jumbo matching the vertical arch trolley is lower than that of artificial drill-blasting method on the artificial and material cost.And the mechanical cost has increased.Thus the mechanization degree of tunnel construction is improved.It greatly reduces the labor intensity of the operating personnel,improves the engineering construction quality and working security.