BEIJING－Chang Benhong felt thrilled as he stood on a parking apron at the top of the China World Trade Center. He could not help but look back on all the impressive changes he has witnessed over the years.

"In those days (1970s and 1980s), China's construction industry was far behind the developed world, and even behind some developing countries," said Chang, one of the construction workers who built the landmark complex located in Beijing's bustling central business district.

He recalled that when China started seeking bidders for the CWTC construction in 1985, no domestic construction firm qualified for the bidding.

"We didn't even know how to handle many of those engineering devices foreign workers had brought here then," Chang said.

Two decades later, when the complex was about to kick off construction of a new tower in 2005, which was once the Chinese capital's tallest building, all bidders were Chinese.

The decades-long story of CWTC is the epitome of China's rapidly growing construction industry.

Official data showed that the total output value of the industry was 26.4 trillion yuan ($4.1 trillion) last year, while in 1952 the figure was only 5.7 billion yuan.

The expansion of the industry also generated job opportunities. The number of employees in the construction sector was less than 1 million in 1952, and by the end of 2020, the number had reached around 54 million, according to the Ministry of Housing and Urban-Rural Development.

Behind such progress were the country's continuous efforts in technological innovation to transform and upgrade the traditional construction sector.

The recent proof is the guideline released last July by 13 central departments to coordinate the intelligent transformation and industrialization of the construction sector.

It calls for efforts to integrate intelligent construction technologies into the whole industrial chain, and sets short and long-term targets for the industry's high-quality development.

To promote the digitalization of the industry, the State-owned Assets Supervision and Administration Commission of the State Council also issued a guideline last year, which urges the use of digital construction models and artificial intelligence technologies.

Through years of persistent efforts in carrying out similar measures, various technologies in China's construction industry have reached world-leading levels.

Construction projects launched by Chinese companies, such as the Mohammed VI Bridge in Morocco and the Mombasa-Nairobi Standard Gauge Railway in Kenya, are gaining international recognition.

According to a 2020 list of top 250 international contractors released by Engineering News-Record, an information provider for the engineering and construction industries, 74 Chinese companies were on the list. They ranked as the largest in terms of business volume, which accounted for over a quarter of the 250 contractors' total.

Fang Qiuchen, chairman of the China International Contractors Association, said the international infrastructure projects contracted by Chinese contractors are rapidly improving in terms of scale, technology and added value.

The role of Chinese contractors has been transformed from solely a contractor to a comprehensive service provider of infrastructure, Fang said.