GB665280A - Improvements in or relating to the underpinning of buildings - Google Patents

Abstract

665,280. Underpinning buildings; foundations. PRYKE, F. Jan. 2, 1950 [Jan. 4, 1949], No. 186/49. Addition to 599,317. Class 20(ii) The method of underpinning buildings described in the parent Specification is modified in that, instead of threading the reinforcing rods longitudinally through the aligned passages through the supporting piers, shoring piers are first erected, each including at least one pair of load-carrying shoring members E, E<SP>1</SP>, Fig. 1, held spaced apart by removable wedge-shaped spacers F, so that when the whole of the damaged substructure has been removed the reinforcing rods J, J<SP>1</SP>, J<SP>2</SP> are inserted laterally from the front of the substructure into the spaces between the members E, E<SP>1</SP> and, by such substitution of the spacers F, one for another as may be necessary, the rods are moved into positions for subsequent embedding in concrete. The shoring piers may themselves be embedded in the concrete but preferably supporting piers, e.g. formed as described in the parent Specification or Specification 629,355, are erected between the shoring piers around the reinforcing rods, the original shoring piers or the parts E, E<SP>1</SP>, F thereof being then removed and the supporting piers embedded in concrete. As shown in Fig. 1, each shoring pier comprises lower and upper plates B, D, a central block C of cruciform shape, all of reinforced concrete, together with two pairs of solid steel plates E, E<SP>1</SP> held apart by steel spacers F, the arrangement being such that on subsequent removal of the plates E. E<SP>1</SP> and spacers F, the plates B, D and block C remain to form part of two supporting piers which have previously been completed by the erection of channel-shaped blocks L between the side limbs C' of the block C and the plates B, D. The wedge spacers F, F<SP>1</SP>, Fig. 4, are shaped to fit against the bevelled side edges of the plates E, E<SP>1</SP> for movement therealong and are each bored with a hole F<SP>2</SP> to receive a bolt G having a nut G' for forcing them towards one another into engagement with the plates E, E<SP>1</SP>. The hole F<SP>2</SP> is screw-threaded to receive the bolt of a releasing tool which after removal of the bolt G is adapted to force the spacers F, F' out of engagement with the plates E, E' while under load. 'The rods J. J<SP>1</SP>, J<SP>2</SP>, Fig. 1, are inserted laterally into the front ends of the spaces between the plates E, E', and further spacers F are then fitted in front of the rods to take the load and permit the spacers behind the rods to be removed so that the rods can be pushed further into the desired positions. This is repeated as necessary. The blocks L are then inserted and mortared in position so that the main rods J pass through their channels whilst the rods J', J<SP>2</SP> lie behind and in front of the pier. Reinforcing loops M, M<SP>1</SP> are also provided together with bent rods K, Fig. 2 (not shown). The spacers F and plates E, E' are then removed and the concrete filled in. In the case of light buildings, the shoring' piers may be made entirely of reinforced concrete and may be embedded in the concrete, in which case, the erection of supporting piers is unnecessary; in such case also the shoring plates may be formed integral with the top or base plates or intermediate plates or blocks. Cast-iron or steel supporting piers may be used in the case of very heavy buildings.