Next-level Technology

By Zhu Mengxiao

When the sun rises, high-speed trains are already lined up for departure from Halim Station of the Jakarta-Bandung High-Speed Railway (HSR)in Indonesia. After seven years of preparation, the first Chinese-built high-speed railway in Indonesia and the Southeast Asian region finally set off, ending ages of anticipation.

“Traffic jams won’t be a problem any more,” said Dinie, a Bandung resident who works in Jakarta. “My journey home just became very easy.” She celebrated the opening of the high-speed rail after years of brutal commutes. In the past, a bus ride could take up to seven hours if a traffic jam happened. Even the old train took more than three hours. The Jakarta-Bandung HSR cuts the trip down to a mere 40 minutes.

The No. 6 tunnel, the longest of the Jakarta-Bandung High-Speed Railway, is completed on February 18,2022. (CHINA NEWS SERVICE)

Dahv, a businessman who frequently shuttles between Jakarta and Bandung, pledged to share the comfortable and convenient highspeed train experience with business partners and family.

Completing the 142.3 km-long high-speed railway required Chinese companies and Indonesian partners to overcome myriad world-level challenges to make technological breakthroughs. Construction showcased the latest achievements of Chinese high-speed rail technology.

Challenging Project

Most of Indonesia’s railways were built when the country was under Dutch colonial rule from the 1600s to early 1900s. When the country gained independence in 1945, the Indonesian government took over the railway facilities and made them a state-run service. However, a lack of funding and technological support left Indonesia’s railway system lagging for decades. Ignasius Jonan, a former minister of transportation, expressed concerns over slow development of Indonesia’s railways. “Personally, I think the government and Indonesian people have ignored trains for a long time,” he said. “Instead, they focused on developing road transportation.”

“At the end of 2021, the total length of railways in operation in Indonesia was 6,466 kilometers, only 11.4 percent of which was electrified,” said Zhang Chao, executive director of KCIC, a China-Indonesia railroad joint venture.For years, only a single railway line connected Jakarta and Bandung. Laid about a century ago, it run at a speed of only 50 km/h.

The natural environment posed a challenge for building a highspeed railway. Java Island, where the Jakarta-Bandung HSR is located, is vulnerable to volcanic eruptions and earthquakes. The ground foundation in Bandung is soft, and it receives abundant rainfall and volatile weather in complicated geological conditions.To tackle these difficulties, higher technological standards were required.

Intelligent sensors and earthquake warning systems are installed in the trains.

Customized Solutions

Plentiful tunnels were necessary to build a high-speed railway across mountainous Java Island. The Jakarta-Bandung HSR includes 13 tunnels with a total length of 16.69 kilometers. The N0. 2 tunnel was the most difficult to dig. It is 1,052 meters in length through a geologically sensitive area.The situation was complicated even further by an existing railway line and nearby mosques and residential areas.Ma Jinchi, deputy general manager and chief engineer of the Jakarta-Bandung HSR project, recalled construction of the No. 2 tunnel.The rainy season there was long. The surrounding rock featured a high liquid limit, high compression ratio,high water content, and high porosity,which meant digging was likely to cause mud outbursts and collapse.Disasters were natural when boring the tunnel.

In October 2021, a sudden mud outburst hit. Muddy water surged and gushed out, instantly filling the tunnel. Ma Jinchi was on site and successfully mitigated the crisis.

Builders conducted endless surveying and measuring and experienced multiple collapses, ground surface subsidence incidents, and sudden mud outbursts.Based on early experience,the project team customized a solution for tunnel digging which combined ground grouting with in-tunnel grouting and used a double-side pilot tunnel method on the upper section.Led by Ma Jinchi, the technical team developed three tunneling machines with utility patents. Application of the machines made the tunnel solid, stable, and more resistant to collapses.Another difficulty was construction of 56 bridges. The design team innovatively designed simplysupported box girders for them.With the weight reduced by around 12 percent, the box girders helped make the bridges more resistant to earthquakes.

No. 17 long-span bridge over the Citarum River, the longest on the route, is vulnerable to flooding during the wet season. Zhang Jinke,head of the project construction team, admitted that alongside geological disasters, they faced a series of difficulties like shortage of filling materials for construction of roads and other supplies. Zhang optimized the work flow and adopted new construction procedures to complete as much construction work as possible during the dry season,successfully shortening construction time from six to four months.

Allan Tandiono, an Indonesia director of KCIC, reported that more than 600 public facilities had to be relocated during the construction of the Jakarta-Bandung HSR, 300 of which involved major efforts. This posed unprecedented challenges for construction. Thanks to efficient coordination between Chinese and Indonesian managers, every problem was eventually solved.

China’s Innovation Going Global

By slashing the journey from three hours to 40 minutes, the HSR solved intercity transportation problems affecting Jakarta and Bandung and facilitated enhanced communication between the two cities. The trains serving the line are based on the key technology of the Fuxing bullet train independently developed by China but adapted specifically for the local environment and railway conditions.Intelligent sensors and earthquake warning systems are installed in the trains, which can move as fast as 350 km/h. Indonesia adopted such transportation technology for the first time as China’s high-speed rail took a big step towards going global.

Technicians from China Railway Electrification Engineering Group Co., Ltd.inspect the equipment before power transmission at the Walini Station of the Jakarta-Bandung High-Speed Railway on May 18, 2023. (VCG)

The Jakarta-Bandung HSR project was China’s first attempt at bringing the whole system, every factor, and the entire industrial chain of its high-speed rails to a foreign country. “Whole system” means that all subsystems of the HSR including its roadbeds, rails,bridges, tunnels, overhead lines,communication signals, train controls, and customer service follow Chinese standards. “Every factor” means that the entire process from surveying and design to construction,equipment manufacturing, operation management, and commercial development is implemented in accordance with China-made protocols. And “entire industrial chain” implies that all equipment used by the railway including engineering machinery, overhead lines, steel tracks, trains, and equipment for communication signals and train controls were manufactured by Chinese companies.These critical independently developed technologies and their corresponding commercialization demonstrate the innovation capabilities of China’s high-speed rail system. China tackled many world-level challenges and set new international standards for the industry.

From follower to pacemaker,China’s high-speed railway technology transcended industry norms by pursuing excellence. The train control system has been the focus of international competition in railway technology. Jiang Ming,deputy chief engineer of the China Railway Signal & Communication Co., Ltd., recounted the R&D team’s efforts to independently develop train control systems. The team spent three years developing and testing new systems and achieved technological breakthroughs that took Western countries decades.

The CTCS3-400T ATP on-board units, independently developed by China State Railway Group Co., Ltd.,is adopted as the core control system to ensure the safety of trains moving at high speeds on the line. The units can effectively lower the probability of equipment failures and ensure safe and highly-efficient operation of the high-speed railway. This technology leads the world.

The opening of the Jakarta-Bandung HSR marks Chinese standards again going global. Via the Belt and Road Initiative, China’s home-developed high-speed rail technologies are injecting new momentum into global infrastructure development.