*
22
Per-
missible
pressure on concrete.
BUILDING (CONSTRUCTION) REGULATIONS, 1956
Gravel,
Kand.
Compact.
Lonxe.
a mixture of mineral grains one quarter inch or more in diameter, and without clay.
a mixture of mineral graina less than one quarter inch in diameter, but retained on a 200 mesh screen.
(a) Coarse sand, Sand consisting chiefly of grains retained
on a 52 mesh screen.
(0) Fixe sand, Band consisting chictly of graine passing a
12 mesh wereon.
a soil which requires the use of a pick for removal.
a soil which is readily removable by shovelling only.
(3) Where the foundation rests on non-cohesive soils, (Type + of Table VIII), the maximum pressure specified in the Table-- (c) shall if the foundation is less than 3 feet in least lateral dimension, be of the pressure specified therein multi- plied by the least lateral dimension in feet, and
(b) may be increased by 5 per cent for each foot of depth below the lowest ground surface immediately adjacent. but shall not in any case exceed twice the pressure specified therein.
(4) Soil tests where required shall be carried out in accord- ance with the requirements of paragraph 860 of the Civil Engineering Code of Practice No. 1-1950-Site Investigation.
29. The pressure on plain or reinforced concrete in founda- tions shall not exceed those specified in Table IX.
TABLE IX.
Pressure on camerate or reinforced concrete foundationa.
Designation as specified in
regulation 19.
Grate IA
IIA
[IA
Grade
I
ΤΙ
III
TV
Maximum pressure in tons per sq. ft.
94
80
H
$ & I 2 8 6 2
441
39
20
16
BUILDING (CONSTRUCTION) REGULATIONS, 1966
30. (0) All piling used in connexion with the foundations of Piling. any building shall to the satisfaction of the Building Authority, be of adequate load bearing capacity; and each pile shall-
(a) be strong enough to carry its load;
(0) transfer its load to the soil in a satisfactory manner;
(c) not cause stresses in the soil, taken in combination with all the piles in the foundation, greater than the proved safe bearing capacity of the soil as determined by tests.
(a) (a) The permitted pile loading shall be such that the vertical pressures in the soil at or below the points of the piles, produced by the loads on all piles în a foundation, shall not exceed the proved safe hearing capacity of such soil as determined by tests.
(b) Piles or pile groups shall be assumed to transfer their loads to the soil by spreading the load uniformly at an angle of 60 degrees with the horizontal, starting at the top of the satisfactory bearing stratum in which they are embedded, and the area considered as supporting the load shall not extend beyond the intersection of the 60 degree planes of adjacent piles or pile groups.
(3) The permissible pile loading shall not be such as to cause excessive movement of the pile relative to the soil. Where any doubt exists, proof of this load shall be obtained from load tests, up to at least twice the proposed working toad.
(4) Every pile shall be driven in such a manner as not to damage the material of the pile.
(5) All piles shall be capped with plain or reinforced
concrete.
(6) Wood piles shall be cut to sound wood before the capping is placed, and the cut-off level shall be below the probable per- manent ground water level.
(7) The authorized architect shall keep or cause to be kept accurate records of materials and principal dimensions of each pile, of the weight and fall of the hammer together with the average penetration of each pile for at least the last five blows and the levels at the bottom and the cut-off of the pile. He shall submit a copy of these records to the Building Authority.