Question

please help with this concrete design mix problem

(40 points) Design the concrete mix according to the following conditions. Perform the necessary computations to determine all ingredients in (kg) per unit volume of mix, and state resources and cite references used for each step. Summarize your design in the table at the bottom, and answer the questions beneath the table. Application Environment Area 52, airport location Idaho, (150m x 50m) runway test section Exposures: freeze-thaw, deicers Design Environment Concrete Requirements: Air-entrained Design compressive strength 27.6 MPa Compressive strength standard deviation 2.1 MPa (more than 30 samples) Runway thickness 457 mm Minimum space between rebar 75 mm Minimum clearance rebar to surfaces 75 mm Admixtures: only shrinkage reducer and accelerant allowed Available Materials Admixtures Shrinkage reducer, at 0.55 kg/m2 Accelerant, CaCL2 at 1% of cement weight Coarse Aggregate Nominal maximum size 63mm, subangular Bulk oven-dried specific gravity 2.85, absorption 3.0% Oven dry-rodded density 1821 kg/m3 Stockpile moisture contents 2.5% Fine Aggregate Bulk oven-dried specific gravity 2.66, absorption 0.5% Stockpile moisture content 2% Fineness gradations (% retained): #100-696; #50-34%; #16-64%, #4-7196, 3/8 in 86% Amount (kg) Ingredients Course Aggregate Fine Aggregate Cement Water Mix density (kg/m3)... Admixtures: Reducer Accelerant

Answer 1

= 27.6 MPa tandard deiatisnm 22I MPa 3 4 75 = 56.25 mm uutis key nemょ2 165 kg/m3, da Contant 26% ere ratioっ0.534 165 /o-S34ュ30 8、98 kg1㎡

cla il Cenuent 3og. 98丿@wxim) ,, , 0.098 m.i air 2 006 water 6s- 563 12 (o 025-0 005) - 1022 S (0 050 03) 130 S3 k1m Amount (l edinb C-R F- A C- A wLzl 30 1 121 9408 A dmiulire 310 k3im Job X1m2 Reduie e lonerよ