GB731262A - - Google Patents

Abstract

731,262. Piles. LEE, D. H. March 28, 1952, No. 7976/52. Class 68(2). A pre-stressable reinforced concrete pile has the head portion 3 provided with one or more deep recesses 13 parallel to the pile axis each of which terminates in a transverse floor 16 to provide a shoulder against which the end anchorage means 15 of a prestressing member 9 can bear, the axial depth of the or each recess being sufficient to accommodate the anchorage means 15 and the projecting end 14 of member 9 below the head surface of the pile and the zone which may deform under driving blows. As shown the pile comprises the head portion 3, intermediate portion 2 and shoe section 1, the portion 2 being hollow and receiving cylindrical portions 10 formed on the head and shoe. Metal ties 11 may secure the portions together by embedding in transverse portions 12 within the hollow section 2. The pile portions are of square cross section with one pre-stressing member 9, such as a steel bar, in each corner, the lower ends being either threaded into the metal driving shoe or point 5 or, as shown, are secured by a nut 20 abutting a thrust plate 21 embedded in the concrete and spaced from the surface 22 of section 1 by a ferrule 23. The upper ends of each bar 9 is tensioned by a nut and washer 15 bearing against an apertured thrust plate 17 embedded in the floor 16 and spaced from the lower face 25 of section 3 by a ferrule 24. In a modification each bar is in threaded engagement with its corresponding plate 71 and the stressing up is done from the shoe end of the pile, the nuts 20 and plate 21 being readily accessible.