"If we knew what it was we were doing, it would not be called research, would it?"  -  Albert Einstein (1879 - 1955)

Objective

The purpose of this assignment is twofold: first, to continue to develop your engineering spreadsheet skills; and second, to develop a complete analysis tool for your reinforced concrete beam project. Basically, this spreadsheet will combine your work from the ACI mix design (Assignment #6) and rectangular reinforced concrete beam (Assignment #7) with an estimate of the reinforced beam cost to predict a cost-adjusted strength-to-weight ratio (ASWR).

Part 1: Compute the ASWR for each beam from the Week 1 data. Average the results for each beam type (the set of beams with no reinforcement, 1 rebar, 2 rebar and 3 rebars) and plot the average ASWR as a function of the number of reinforcing bars.

Part 2: Develop a spreadsheet to predict the ASWR of a rectangular reinforced concrete beams in bending without considering shear reinforcement in the beam weight or beam cost. Use the spreadsheet to predict the ASWR for the reinforced concrete beam displayed in the sample interface sheets shown below.

• Input parameters should include: the height and length of the beam, the amount of reinforcement material (both tension and shear), the compressive strength of the concrete, the yield stress of the reinforcement, the unit weight of the concrete, the minimum concrete cover for the reinforcement, the minimum spacing between rebars, and the shear reinforcement spacing.
   

• From these inputs, you should compute the minimum width of the beam b, the depth to the center of the reinforcement d, the area of steel in tension A_s, the area of steel is shear A_v, the b₁ constant, The height of the Whitney stress block a, and depth to the neutral axis c, the c/d, the predicted  strength in tension, shear, and compress, the weight of the beam, the SWR, the cost of a single beam, and the Adjusted SWR.  
   

• In addition, check to see if the reinforcement yields before the concrete crushes (see class notes) and that the reinforcing bars fit into the proposed beam. 
   

• Develop an interface for your spread sheet similar to the shown below. Note the addition of the cost per beam and the ASWR.

• Compute the cost of the reinforced concrete beam on the "ACI Mix" sheet of your workbook. Use the format shown below. Note the costs of concrete materials and steel rebars is included (see cost sheet for details). Also notice that this sheet includes the new values for the material parameters. Values for the concrete compressive strength, the dimensions of the beam, and the volume of steel are available from the "Rectangular Beam Analysis" sheet.

Use your spreadsheet to predict the ASWR for the following reinforced concrete beam: 

Requirements

Lastly, a web page describing the CIVL 1112 homework policy is available. Read it before you turn in this assignment. You will be graded throughout the semester according to the policy outlined in it.

Coversheet for homework

This website was originally developed by Charles Camp for CIVL 1112.
This site is maintained by the Department of Civil Engineering at the University of Memphis.
Your comments and questions are welcomed.