Photo credits - Concrete Takeoff Pro site (all from Wikimedia Commons; resized/compressed for web)

hero-concrete-pour.jpg
  Source: https://commons.wikimedia.org/wiki/File:US_Navy_070515-N-0938M-005_Seabees_attached_to_Naval_Mobile_Construction_Battalion_(NMCB)_133_pour_concrete_into_a_concrete_pad_located_inside_the_expansion_area_of_Camp_Lemonnier.jpg
  Author: U.S. Navy photo by Lt. Edward Miller
  License: Public domain (U.S. federal government work)

rebar-slab.jpg
  Source: https://commons.wikimedia.org/wiki/File:Rebar_framework_in_preparation_of_pouring_a_concrete_slab_at_the_Metro_North_express_level._08-08-2019_(48497323626).jpg
  Author: MTA Capital Construction Mega Projects (https://www.flickr.com/people/59595815@N03)
  License: CC BY 2.0 - https://creativecommons.org/licenses/by/2.0/ (attribution required; resized/cropped)

foundation-formwork.jpg
  Source: https://commons.wikimedia.org/wiki/File:Foundation_formwork.webp
  Author: Wikideas1
  License: CC0 1.0

concrete-pump-truck.jpg
  Source: https://commons.wikimedia.org/wiki/File:Concrete_pump_truck_-_Arlington,_MA.jpg
  Author: Daderot
  License: CC0 1.0

concrete-building.jpg
  Source: https://commons.wikimedia.org/wiki/File:Concrete_car_park_(51486365671).jpg
  Author: Alex Liivet (Chester, UK)
  License: CC0 1.0