Explain does why:
• On the basis of qual workability the surface characteristicsof aggregate have a limited impact on the ultimate strength ofconcrete.
• the surface characteristics of aggregate have a clear impacton ultimate strength of concrete on the basis of qual watercontent.
• The cylinder strength is higher than that of cube's.
• The aspect ratio of concrete cylinders has no impact oncompressive strength obtained in compression testing machine withbrush platens.
• Concrete bridges should not be subjected to stress levelshigher than 0.55 of ultimate strengths.
• the maximum aggregate size of aggregate have two opposingeffects on concrete strength.
