Recently, at the metro construction site in the Pidu District section of the Phase I and II works of Line 6, invested and constructed by China Railway Construction Kunlun Investment Group, two pieces of good news arrived at once: the right line of the running tunnel between Pitong Station and Heping Street Station was successfully holed through, becoming the first running tunnel in the Pidu District to be completed; the main structures of Heping Street Station, Luxiao Station, and Zhonghe Station were also capped on the same day. At this point, apart from Xipu Station, the main structures of the remaining seven stations in the Pidu District section of the line have all been capped.

As one of the "governing meridians" of the Chengdu metro network, the Phase I and II works of Line 6 start from Wangcong Temple Station in Pidu District in the north, pass through Gaoxin West District, Jinniu District, Chenghua District, and Jinjiang District, and end at Guandong Road Station in Gaoxin District in the south, running overall north-south with a total length of about 47.0 km. Within Pidu District there are a total of one depot and eight stations.

The area lies in a large-grain boulder-cobble stratum geology, and also faces difficulties such as complex underground pipelines and dense buildings. In order to fulfill the construction milestones of each station and running tunnel with guaranteed quality and quantity, and to connect Juanrong and shorten the distance between urban and suburban areas as early as possible, the Kunlun Group Metro Company organized all participating parties to increase investment and ensured the smooth lowering of all 14 shield machines in the district. Heping Street Station needed to provide conditions for the shield machine to pass through the station and had to be capped by the end of 2017, so the schedule pressure was extremely great. To ensure the milestone was met, the Kunlun Group Metro Company intensified organization and coordination; the main structure of the station was capped in only 73 days, setting the fastest construction record for a standard station on the entire line and creating favorable conditions for the shield machine to pass through the station.

Pidu District is located in a large-grain boulder-cobble stratum. Under such stratum conditions, shield construction has the characteristics of high requirements for earth chamber pressure control and muck conditioning, high wear on the cutterhead, and great construction difficulty. The Kunlun Group Metro Company attached great importance to this, successively organizing several shield construction management experience exchange meetings, and at the same time organizing technical management personnel from all participating units to study the tunneling experience in similar strata on other lines and the relevant management measures of Chengdu Rail Transit Group, and organizing shield operators to learn on the job in advance at sister units. During launching, in response to the stratum characteristics, process control was strengthened, and the joint duty system of all units during launching, arrival, and crossing of major hazard sources was strictly implemented; geological survey was intensified and active drilling was carried out; 23 expert meetings were held, the chamber was opened to remove stones 21 times, 475 ground reinforcement holes were drilled, and 272 cutting tools were replaced, safely and efficiently achieving the holing-through of multiple running tunnels.

Up to now, the main structures of 17 stations in the Phase I and II works of Chengdu Metro Line 6 have been capped, 21 stations are undergoing structural construction, and 29 shield machines have been lowered, creating ample conditions for the holing-through of the entire line next year.