TABLE P6.36 Cylinder no. Water submergence (days) 3 4 5 3 7 14 28 Compressive strength of plain concrete (psi) Compressive strength of concrete with accelerator (psi) 1197 2437 3243 124 4120 3696 954 2272 3097 4122

Note:hand written solution should be avoided.

Working on major construction project that requires considerable amounts of concrete to be used,you are asked to design a concrete mix following the BRE methodology. All the necessary tables forthis can be found in the Appendix. The concrete mix specifications are:o Characteristic compressive strength of 35 N/mm 2 at 28 days.o Failure rate of 2%o Previous control data yielded a standard deviation of 10 N/mm 2o CEM-I 42.5o Air-entraining is not requiredo Maximum water to cement ratio 0.40o Minimum cement content 390 kg/m 3o Required slump 50 mmo Coarse aggregate: Crushed maximum size 20mmo Fine aggregate: Uncrushed with 90% passing 600 μm sieveo Relative density of aggregates: 2.5o Coarse aggregate has 4% moistureo Fine aggregate is dry and has 1.2% absorption.o Volume of the required trial mix: 0.090 m 3Following the BRE step-by-step process estimate the water content of the mix estimate the content of aggregates, provide the estimated mix quantities

A concrete test cylinder with a cross-sectional area of 28.3 in squared is to be tested in axial compression. Before loading two marks are scribed on the cylinder precisely 8 in apart (as shown in the figure below) when the load is 40,000 lb the marks are measured and found to be 7.997 in apart determine the E value for this concrete. Assume an approximately linear relationship between stress and strain.