Anton Matthews, maker of the Stone-Safe memorial fixing system that he demonstrated against a ground anchor fixing system near his premises in Bognor Regis earlier in the year (see bit.ly/fixing-test), contends that the ground at Towcester Road cemetery, where the National Association of Memorial Masons (NAMM) has carried out tests on memorial fixing systems that have led to the approval of several ground anchor fixing systems, contains obstacles that make the systems seem more secure than they are in the worst conditions.
BS 8415 requires fixing systems to be tested in soil conditions of medium sand and gravel into which a 50mm square, sharpened wooded stake can, with some difficulty, be driven using a hammer with a mass not exceeding 5kg.
NAMM criticised Anton's demonstration of his and a NAMM-approved fixing system earlier in the year, saying the ground conditions were unrealistic and in such conditions masons would not use a single ground anchor. Anton says he has since carried out the test again under the conditions he created using three ground anchors and the system still failed to stand up to a 150kg loading, as required by BS 8415.
Anton says the ground conditions in his demonstration, created by digging a hole and filling it with medium coarse sand, removed any possibility of rocks or roots influencing the results. He believes the ground conditions where NAMM has carried out its tests include such obstacles close enough to the surface to influence the result of the tests. He obtained permission to examine the soil at Towcester Road cemetery in the area where NAMM has carried out its tests. The video above shows him doing this.