The width of the bridge which has a 6-lane carriageway (3 lane vehicular traffic in each direction) is 24m. The reinforced concrete abutment on each bank of the river is 28m long and 4m wide with an average height of 4m. For the construction of the abutments (cast in several sections in-situ) initially two different concrete mixes need to be designed. The following requirements have to be met: The characteristic strength of the concrete in the abutments is 40MPa The maximum internal temperatures, monitored by thermocouples embedded in the abutments should not be exceed The mix should have a minimum slump of 100mm a) Design two mixes, one with flyash/cement as a binder and the other with slag/cement as the binder. Give proportions of all ingredients per m3 of concrete. b) Compare the two mixes in relation to heat of hydration and recommend a mix for the final construction. c) The structure is located in a coastal zone. What are the design considerations you need to ensure durability against chloride induced corrosion d) Prepare a material specification for the above project considering strength and durability requirements (One page)