At the end of 2023, the diaphragm wall retaining structure works at Ma'anshan Park Station in Work Zone 8 of the Guangzhou East–Huadu Tiangui Intercity Railway project (referred to as the "Guanghua Intercity Railway"), general-contracted by Guangzhou Construction Co., Ltd., were successfully closed. The Guanghua Intercity Railway starts at Guangzhou East Station on Guangzhou Metro Line 18, runs north through Jingxi Road, Baiyun Dongping, and Baiyun City Center, connects Fangshi, Fenghuang South Road, and Ma'anshan Park, and terminates at Huadu Huacheng Street Station. It comprises 7 newly built stations, with a line length of 39.6 km and a design speed of 160 km/h. As part of the Guangzhou metropolitan area intercity network and a major north–south rail transit artery of the Guangdong–Hong Kong–Macao Greater Bay Area, once completed the project will link with the future Nanzhongzhu Intercity Railway via Guangzhou Metro Line 18, greatly shortening travel times for north–south connections within Guangzhou as well as cross-city travel to Zhuhai and Zhongshan.

Ma'anshan Park Station is 265 m long and 24.5 m wide, with a foundation pit excavation depth of 26.9–28.8 m. The diaphragm wall serving as the retaining structure is divided into 144 panel sections, with a wall thickness of 1 m and a wall depth of 29.0–34.7 m, using the double-wheel trench cutter with the overlap (chained) joint type; in addition, there are 7 unreinforced panels at the north end and 5 panels for Shafts No. 1 and No. 2 in Work Zone 7, totaling 156 panels. The diaphragm walls were jointly completed by specialized subcontractors Guangzhou Yuesheng Construction Industry Co., Ltd. and Guangdong Zhengmao Technology Engineering Co., Ltd.

The total quantity of the diaphragm wall works is approximately 16,900 m³, of which the soil and sand layers total approximately 9,600 m³, moderately weathered rock approximately 7,000 m³ (maximum rock strength 64.4 MPa), and slightly weathered rock approximately 300 m³ (maximum rock strength 134.6 MPa). Rock accounts for 43.2% of the total diaphragm wall quantity, and the rock portion was constructed using a combined "drilling and milling" process. Ma'anshan Park Station is an interchange with the existing Guangzhou Metro Line 9. The site reveals karst caves (cave encounter rate 12.7%) and thick sand layers (maximum thickness 16.3 m), posing risks such as excessive horizontal displacement, ground settlement, and collapse.

Guangdong Zhengmao deployed one Bauer MC 86 trench cutter on this project. According to the project department's arrangements, construction was carried out in two phases (13 panels had already been completed by another company in the earlier stage). The first phase ran from March 1 to June 27, 2023 (including a 14-day suspension in March due to project arrangements), with no night work, and a total of 49 panels were completed. The second phase ran from September 8, 2023 to January 2, 2024; with the Bauer MC 86 trench cutter operating almost 24 hours a day, a total of 98 panels were completed. Over nearly 4 months, the MC 86 trench cutter operated consistently and stably, completing an average of 24 panels per month.

The MC 86's advanced cabin design and layout keep overall equipment noise low, providing favorable conditions for night construction. Under complex working conditions, the MC 86 trench cutter's energy consumption is relatively low; according to the user's records, the project's overall average fuel consumption was only about 52 liters/hour. Despite rock accounting for a high proportion of 43.2%, the average fuel cost of the double-wheel trench cutter was less than 90 yuan per cubic meter of output. The MC 86 trench cutter's efficient construction capability, low fuel consumption, and stable production output helped better control costs for the overall diaphragm wall construction.

Through the meticulous early-stage planning of the project department of the general contractor Guangzhou Construction Co., Ltd., and months of close collaboration between the subcontractors Guangzhou Yuesheng Construction Industry Co., Ltd. and Guangdong Zhengmao Technology Engineering Co., Ltd., the diaphragm wall retaining structure works at Ma'anshan Park Station in Work Zone 8 were ultimately completed 5 days ahead of schedule, laying a solid foundation for the smooth implementation of subsequent phased works such as foundation pit excavation and station construction.