BEIJING (Reuters) - China will set up a state infrastructure investment fund worth 500 billion yuan ($74.69 billion) to spur infrastructure spending and revive a flagging economy, two people with knowledge of the matter told Reuters on Tuesday.

China's economy has started a slow recovery from the supply shocks caused by extensive lockdowns since the second quarter, although headwinds to growth persist, including from a still subdued property market, soft consumer spending and fear of any recurring waves of infections.

The fund is expected to be set up in the third quarter, the sources said.

China has unveiled a raft of economic support measures in recent weeks, although analysts say the official gross domestic product target of around 5.5% for this year will be hard to achieve without doing away with its strict zero-COVID strategy.

Much of the economic support has come from fiscal stimulus to counter the impact from COVID-19 this year, with the central bank steadily easing liquidity conditions to lower financing costs.

Authorities are doubling down on an infrastructure push, dusting off an old playbook to revive the economy, pledging 800 billion yuan in new credit quota and 300 billion yuan in financial bonds for policy banks to support big projects.

Sources told Reuters that China will issue 2023 advance quota for local government special bonds in the fourth quarter, with the new quota likely bigger than 1.46 trillion yuan for 2022.

The Ministry of Finance and the National Development and Reform Commission did not immediately respond to Reuters' requests for comment.

The cabinet has told local governments to ensure 3.45 trillion yuan in special bond issuance for infrastructure - part of the 2022 special bond quota of 3.65 trillion yuan - is completed by the end of June.

($1 = 6.6939 Chinese yuan renminbi)