two arches

arc arch architecture archway arrangement assembly bend bow build caked calcified cast cement compact composition compressed conception congealed conglomerated consolidated constitution construction contour curvature cut development disposition dome dried edifice elevation erecting erection fabric fabricating fabrication figuration figure firm form format formation foundation improvisation indurate invention makeup making manufacture mold monolithic origination outline petrified plan planning poured precast prefab prefabrication raising roadwork semicircle set shape solid solidified span strong structure system systematization turn type unyielding vault