<；P>；PROBLEM TO BE SOLVED: To provide a torsion-preventing structure for arch members in a hothouse structure enabling firm fixation of arch pipes in a hothouse structure even when power is applied to the arch pipe in a direction corresponding to a torsional position. <；P>；SOLUTION: The torsion-preventing structure for arch members in a hothouse structure is as follows: two arch pipes 4, 5 different in a curvature from each other are connected with a transverse pipe 2 set up in a ridge direction； a chin-propped member C almost in an isosceles triangular shape in a plan view is set up between the larger arch pipe 4 and the transverse pipe 2 while the smaller arch pipe 5 of the two arch pipes and the transverse pipe 2 are connected in an intersecting condition； the chin-propped member C includes a holding-over part 50 having an almost U-shape in plan view which holds over the larger arch pipe 4, and an arm part 51 which extends to the holding-over part 50 as an ending point； and the arm part 51 is set up to the member C so as to stride over the fixation part where the smaller arch pipe 4 and the transverse pipe 2 are connected. <；P>；COPYRIGHT: (C)2010,JPO&INPIT
