1950-, Civil Engineering The Runway Job,3

STEALING STONEThere is a road in Belfast known as The Limestone Road and many years ago, long before the Hitler War, limestone was quarried in the hills above the Horseshoe Bend on the North side of Belfast. It was ground up, and taken by that road to the docks in bogey trucks. The ‘road’ was really a sort of railway, and until recently there was a short narrow street just off the Limestone Road, near North Queen Street, called Tramway Street, where the trucks were parked in a siding when not in use.. At the docks the limestone, which was of a soft nature was loaded to be shipped to England – I’m told, to mix in chicken feed to improve the egg shells. What was unsuitable, contaminated with clay or overburden, had been stacked to one side in the quarries until they were so full of waste they became unusable as quarries and closed down. I found this material one day when we were looking for a source of filling and amazingly it turned out to be the most useful and satisfactory filling of all. The very clay content which made it unsuitable in the first place, when mixed with the limestone which also was so soft in part, made up the whole material when crushed down tight into a homogeneous mass. When it had dried out it was like concrete. I mention this purely out of interest.
The other stone we used was for making concrete was just as difficult to find. We needed a stone which crushed down into pieces as near cubic in shape as possible, but unfortunately, in the Belfast area most of the stone while being basalt is more like slate and crushes into a flatter section. In the end we were successful, but thereby hangs a tale. One of my jobs was to check on materials and this day I could not make the amount of concrete agree with the amount of stone we had paid for to make the concrete. As we were using a very sophisticated method of making concrete where the quantities of the various materials were accurately measured, there was no way the discrepancy of having bought some thirty percent more stone than we should have used could be accounted for. Others checked the books with the same result, – something serious was amiss. First we checked the weigh-bridge which we had installed at the edge of the site.
There are stories throughout the building industry of lorries defeating the system. With sand it is a matter of spraying with water just near the site so the buyer is buying useless water at the price of sand. The solution, if that is suspected, is to refuse to weigh the lorry until water has stopped dripping. A certain amount of moisture is essential to stop the sand blowing during transport and this is what unscrupulous contractors sometimes play on.
Then there is the old chestnut of the lorry going in one gate, being checked, going out another gate and then going round again to be checked yet again. It was with this in mind we set up our own weigh bridge and checking system and it was therefore impossible to believe we had been hoodwinked. We filled one of our own lorries, sent it to the Town weigh bridge and then checked it on our own. It was fine, so there was nothing wrong with our equipment.
It is usual on a site to weigh the contractors’ lorries empty and to note the weight which is known as the ‘tare weight’. This saves having to weigh the lorries full and empty every trip and provided nothing has changed, the system works, except when the initial weight has been fiddled by removing all the surplus weight such as the jack, and the spare wheel and then subsequently carrying it If a lorry is making a great number of trips something as simple as that can amount to quite a sum on a big job. We checked that too, then we set our boxer friend to sit near the weigh bridge with a novel, and look like someone unemployed enjoying the sun.
It paid off. The weighbridge was level in itself but had been built on sloping ground. The lorries were very long with two axles at the back. The system we had agreed with the contractor was that the weigh bridge man would see the front wheels of the lorry onto the weigh bridge, go into his office and press a button, the weight would then be recorded automatically, he would then wave through the window and the lorry would slowly move forward until the back two sets of wheels were on the bridge and the front ones off. He would then weigh again and the sum of the two weights less the tare weight was what we paid for.
Our boxer friend found that unfortunately this was not the case. When the bridge man had seen the lorries onto the bridge and was on his way into the hut, the lorries would ease that little bit more forward until half the back wheels were on the bridge as well as the front ones, then, when the bridge man waved, the lorry would ease forward again and the two back axles were weighed. What was happening was that we had been unwittingly weighing one set of back wheels twice.
Nothing could convince us that after all the money we had paid out, the stone supplier was not surprised at his profit margin, it was too large to escape notice.

Categorized as General

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