Women's rugby sevens appears at the Olympics for the first time and Joyce, 20, is the only Welsh player to make the otherwise all-English GB squad.
"We're coming out here to achieve a medal and hopefully gold," she said.
"Sevens is a game anything can happen, anyone can win. You might be up top and five seconds later you're losing."
On the prospect of facing Brazil in their opening Pool C game, Joyce said: "We're just going to take it like it's any other team, go out there fighting. It's going to be one of our hardest games."
Team GB also face Japan on Saturday, before a match against Canada on Sunday with the quarter-finals to follow.
The only non-English member of the squad, Joyce says she has settled in well and is enjoying the experience.
"The facilities here are amazing, we are loving every second of it," she said.
"We get free time and chances to play monopoly, cards and we're all loving Mario Kart [a video game].
"It's honestly amazing and one of the best experiences I can ever imagine."
The Team GB squad have now arrived in the athletes' village in Rio after a training camp in Belo Horizonte.
"I think it's going to be completely different level of excitement in the athletes' village. It will be amazing to get to be with everyone else," said Joyce.
"Imagine just walking past Usain Bolt, Mo Farah and Andy Murray. It would be a dream come true."
Joyce, from St David's in west Wales, is the first Welsh women's rugby player to compete in the Olympics, something which she says is "pretty insane".
"I'm getting so much support," Joyce added.
"When I went home a couple of weeks ago to my parents' house they had the GB flags and the Welsh flags all around the house.
"I live in a little city and they're all cheering for me and wishing me good luck, giving me cards. I've had amazing support."
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Some £85,000 was spent by the council to improve a nine mile (14.5km) section of the A4059, between Aberdare and Abercynon, which is prone to flooding.
It was part of a £23m scheme to improve roads in the area.
Council leader Andrew Morgan said road improvements "continue to be a key priority when it comes to allocating our financial resources".
The road, known locally as the "Letty Turner's bends" has also had its drainage system improved.
Councillor Morgan said: "We will be investing over £23m in highways improvements, infrastructure and strategic projects over the next three years - this is on top of the £53m we have already invested since 2011 meaning that by 2018/19 we will have invested over £76m in these key areas in recent years."

The 35-year-old victim was attacked outside Barclays Bank in London Road, North End, Portsmouth at about 15:20 BST on Saturday.
The men, aged 41 and 42, were arrested on suspicion of murder and conspiracy to murder. They are both in police custody.
It is understood the victim's injuries are not thought to be life-threatening.
Police said they are appealing for witnesses.

Christopher Colegate, 69, was found in the road at the junction of Heath Avenue and Darby's Lane in Poole, at about 19:30 GMT on Friday 13 December.
He suffered significant injuries and later died at Poole Hospital.
Despite numerous appeals and rewards of £11,000 being offered, the driver of the car has never been found.
Dorset Police have renewed their appeal for witnesses.
Officers believe a light-coloured VW Golf Mark 4, made between 1998 and 2005, was involved in the collision.
Mr Colegate, from Poole, walked with a "distinctive stoop" and used two walking sticks.
Inspector Matt Butler, of the Dorset Police traffic unit, said: "We still do not know exactly what happened to Mr Colegate.
"We know that a number of cars were in the area at the time of the collision.
"Some we have traced but we have not been able to identify a Golf driver that travelled along Heath Avenue toward Wimborne Road at around the time of the incident."
Dorset Police and Crimestoppers are still offering a £10,000 reward, while Oakdale Conservative Club, which Mr Colegate regularly attended, has offered an extra £1,000.
Team GB rugby sevens wing Jasmine Joyce says her side are aiming for an historic gold in Rio as they prepare to take on hosts Brazil on Saturday.
[NEXT_CONCEPT]
Work to help prevent flooding on a main road in Rhondda Cynon Taff has been completed.
[NEXT_CONCEPT]
Two men have been arrested after a woman was stabbed in the back as she walked in a busy shopping street.
[NEXT_CONCEPT]
A hit-and-run driver who fled a collision in which a man was killed in Dorset is still being hunted a year on.