| 摘要 |
1. Process for altering a roof truss, the said truss (1) being situated between two gable walls (20, 21) - possibly pointed - and comprising a series of gable trusses (2) extending from one front wall (3) to another (4), being disposed at a short distance ("D") from each other between the said front walls so as to form the necessary supports for the roof, and consisting principally of a horizontal beam (5) called a "tie-beam" and two inclined wooden members (6, 7) called "principal rafters", which, in non-convertable rooves, are connected to each other by means of triangular elements such as braces (8, 9, 10, 11) supporting the principal rafters so that the latter can resist the bending stress to which they are subject on account of the weight of the roof, this alteration process being characterised in that, before the triangular elements of each principal rafter are removed, - a vertical slide (12) is firstly secured between the principal rafter (6, 7) and the tie-beam (5) of at least a plurality of gable trusses (2), - beams (15) are simultaneously introduced into the roof and engaged in the slides (12), the said beams having first been divided into a plurality of sections (16, 17, 18 and 19) and the ends of the beam (15) are secured in the gable walls (20, 21) respectively, the sections (16, 17, 18, 19) of the beam being joined by joining means (22, 23 and 24), under each of which is secured a strut (25, 26 or 27), - the base of each of the struts (25, 26 or 27) is then secured by one of the ends of two beam ties (31 and 32) the other ends of which are connected, at least indirectly, to those of the beam sections situated on both sides of the strut in question, - finally, the beam ties are brought into action and, by acting on the strut with which they form a triangle, support the beam, which in turn at least indirectly supports the principal rafters and the roof, which thus allows for the removal of the original triangle of the gable trusses (2) and then for the lining of the roof. |
