2010 Guatemala City sinkhole and donation centers for victims of the storm were opened across the country. According to the Office for the Coordination of Humanitarian Affairs (OCHA), schools in Guatemala were to be closed until at least June 4. Immediately after the sinkhole's collapse, there were plans to fill it in with a soil cement made from cement, limestone, and water known locally as "lodocreto" ("mudcrete"). This substance was also used to fill in the 2007 Guatemala City sinkhole. However, another technique, which geologists call the graded-filter technique, in which the sinkhole is filled with successive layers of boulders, smaller rocks, and gravel,
Void (composites) void content of approximately 1% is appropriate for performance while other grades of composites can have between 3%-5% void content. A small change in the percentage of void content may not seem like a large problem however for a loaded carbon fiber laminate composite, a 1%-3% increase in void content can reduce the mechanical properties of the composite by up to 20% Void content in composites is represented as a ratio, also called void ratio, where the volume of voids, solid material, and bulk volume are taken into account. Void ratio can be calculated by the formula below where e