Weed control in joints of concrete block and other paving stone

摘要

The present weed reducing material reduces the necessary weed control work by making joint filling sand a hostile substrate for plant and fungus growth by using an environmentally acceptable slow release mineral additive. The additive, having similar grain size distribution, mechanical and rheological properties, forms an integral part of the joint filling sand. The specific gravity of the additive is lower than quartz sand imparting a tendency for the additive to migrate towards the top part of the joint. The additive leads to pore waters rich in sodium and at high pH, both qualities being maintained over long periods. The mixture of additive and sand is handled and applied using conventional laying techniques and equipment, observing usual precautions for mortar or cement mixes with sand. In the environment, reaction with CO2 in the air or in the soil porosity inactivates the causticity, yielding harmless carbonate salts.

主权项

1. A herbicidally effective weed control pavement joint filling loose granular sand mixture, which is not a mortar or cement mixture, consisting essentially of a granular sand mixture of quartz sand and at least one sodium containing substance selected from sodalite or silicate containing glass, wherein a concentration of sodium formed in an aqueous phase of the sodium containing substance for providing sustained release of sodium in the aqueous phase and filling pores of the joint filling granular mixture when wetted by rain water, wherein a ratio of a mass of sodium containing substance mass of sand is between 0.5/99.5 and 10/90, wherein the pavement joint filling loose granular mixture retains loose granularity after application to desired pavement joints.