Source: HS2HS2 announced plans to refine the Grimshaw-designed scheme last yearHS2 has submitted a planning application to Birmingham City Council for an amended design for Grimshaws new Curzon Street station.Consent for an outline scheme was secured from the council in 2020, but HS2 announced intended refinements to the scheme in September last year.The amended scheme has now been submitted for consideration, with a total of 14 changes proposed.Source: HS2 LtdWork has already begun on the Curzon Street siteThe roof cassette and roof edge, previously meant to be made from timber and concrete respectively, will now be aluminium.Five concourse areas will be reconfigured to improve accessibility and passenger experience.Curzon Street is already under construction by a joint venture of Mace and Dragados.Elsewhere on the scheme, the giant HS2 box structure under the A46 in Warwickshire is approaching the final phase of construction.Balfour Beatty Vinci has installed 120 gigantic concrete beams using three giant cranes to form a major part of the top of the structure.The box structure near Kenilworth is due for completion later this year.