The government said that the measures may make attending the games less comfortable for visitors but they would result in greater security.
The Games are expected to attract as many as 500,000 foreign visitors.
"The attack in Nice is worrisome for us too. We will review procedures, make more barriers, more spot-checks on visitors and roadblocks", said Defence Minister Raul Jungmann.
The authorities had previously declared public holidays and banned trucks from certain areas of Rio during the Olympics to ease congestion and improve emergency response capabilities.
Rio`s mayor, Eduardo Paes, said security would be beefed up for Olympic delegations from countries which have been targeted.
Mr Paes did not give any further details, but the head of French military intelligence said France had been informed of a planned terror attack on its team at the Rio Games.
Gen Christophe Gomart told a parliamentary commission in May that a "partner agency" warned of the plot by a Brazilian Islamist militant.
The transcript of the hearing was made public this week.
"Brazil is confident about its preparations. We are employing the most modern security and defence techniques", Sports Minister Leonardo Picciani told Reuters news agency.
Earlier this week, Mr Picciani said the armed forces would get an extra $24m (£18m) to help them meet security needs.
The military would begin patrolling sports venues from 24 July, he added.
More than 80,000 police and soldiers will patrol the streets of Rio for the duration of the games.
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