18.—(1) This paragraph applies to determine the maximum weight that may be transmitted to the road surface by the wheels of any engineering plant that is a wheeled vehicle or a wheel-track combination vehicle.
(2) The wheel weight of the plant must not exceed 11,250 kilograms.
(3) The weight transmitted to any strip of road surface on which the wheels of the plant are resting must not exceed the following limits (measuring the strip of road surface referred to in those limits as the distance contained between any two parallel lines drawn on the road surface at right angles to the longitudinal axis of the plant)—
(a)if the strip of road surface measures a distance of 0.5 metre or less, the weight must not exceed 45,000 kilograms;
(b)if the strip of road surface measures a distance that lies between 0.5 metre and any greater distance up to, and including, 2 metres, the weight must not exceed the sum of—
(i)45,000 kilograms; and
(ii)an additional weight allowance which is to be calculated by reference to the difference between 0.5 metre and the overall measurement of the strip of road surface, with additional weight being allowed in respect of that difference at a rate of 30,000 kilograms per metre;
(c)if the strip of road surface measures a distance of more than 2 metres, the weight must not exceed the sum of—
(i)the weight determined in accordance with paragraph (b), as calculated in respect of the first 2 metres of the measurement of the strip of road surface; and
(ii)a further additional weight allowance which is to be calculated by reference to the difference between 2 metres and the overall measurement of the strip of road surface, with further additional weight being allowed in respect of that difference at a rate of 10,000 kilograms per metre.
(4) But where the plant has one or more wheels that are not fitted with a pneumatic tyre, the total weight transmitted to the road surface by—
(a)any such wheel (if no other wheel is in the same line transversely); or
(b)all such wheels as are in line transversely;
must be such that the average weight per 25 millimetres width of tyre in contact with the road surface does not exceed 750 kilograms.
19.—(1) This paragraph applies to determine the maximum weight that may be transmitted to the road surface by the tracks of any engineering plant that is a track-laying vehicle or a wheel-track combination vehicle.
(2) The weight transmitted to any strip of road surface on which each track of the plant is resting must not exceed the following (measuring the strip of road surface referred to in those limits as the distance contained between any two parallel lines drawn on the road surface at right angles to the longitudinal axis of the plant)—
(a)if the strip of road surface measures a distance of 0.5 metre or less, the weight must not exceed 11,500 kilograms;
(b)if the strip of road surface measures a distance that lies between 0.5 metre and any greater distance up to, and including, 2 metres, the weight must not exceed the sum of—
(i)11,500 kilograms; and
(ii)an additional weight allowance which is to be calculated by reference to the difference between 0.5 metre and the overall measurement of the strip of road surface, with additional weight being allowed in respect of that difference at a rate of 7,500 kilograms per metre;
(c)if the strip of road surface measures a distance of more than 2 metres, the weight must not exceed the sum of—
(i)the weight determined in accordance with paragraph (b), as calculated in respect of the first 2 metres of the measurement of the strip of road surface; and
(ii)a further additional weight allowance, which is to be calculated by reference to the difference between 2 metres and the overall measurement of the strip of road surface, with further additional weight being allowed in respect of that difference at a rate of 2,500 kilograms per metre.