The bond behavior of reinforcing bars is an important determinant of strength and stability. The article “Experimental Study on the Bond Behavior of Reinforcing Bars Embedded in Concrete Subjected to Lateral Pressure” (J. of Materials in Civil Engr., 2012:125–133) reported the results of one experiment in which varying levels of lateral pressure were applied to 21 concrete cube specimens, each with an embedded 16-mm plain steel round bar. and the corresponding bond capacity was determined. Due to differing concrete cube strengths (fcu, in MPa), the applied lateral pressure was equivalent to a fixed proportion of the specimen’s (0, .1fcu, … , .6fcu). Also, since bond strength can be heavily influenced by the specimen’s fcu, bond capacity was expressed as the ratio of bond strength (MPa) to .
Pressure | 0 | 0 | 0 | .1 | .1 | .1 | .2 |
Ratio | 0.123 | 0.100 | 0.101 | 0.172 | 0.133 | 0.107 | 0.217 |
Pressure | .2 | .2 | .3 | .3 | .3 | .4 | .4 |
Ratio | 0.172 | 0.151 | 0.263 | 0.227 | 0.252 | 0.310 | 0.365 |
Pressure | .4 | .5 | .5 | .5 | .6 | .6 | .6 |
Ratio | 0.239 | 0.365 | 0.319 | 0.312 | 0.394 | 0.386 | 0.320 |
- a. Does a
scatterplot of the data support the use of the simple linear regression model? - b. Use the accompanying Minitab output to give point estimates of the slope and intercept of the population regression line.
- c. Calculate a point estimate of the true average bond capacity when lateral pressure is .45fcu.
- d. What is a point estimate of the error standard deviation σ, and how would you interpret it?
- e. What is the value of total variation, and what proportion of it can be explained by the model relationship?
The regression equation is
Ratio = 0.101 + 0.461 Pressure
Predictor | Coef | SE Coef | T | P |
Constant | 0.10121 | 0.01308 | 7.74 | 0.000 |
Pressure | 0.46071 | 0.03627 | 12.70 | 0.000 |
Analysis of Variance
Source | DF | SS | MS | F | P |
Regression | 1 | 0.17830 | 0.17830 | 161.37 | 0.000 |
Residual Error | 19 | 0.02099 | 0.00110 | ||
Total | 20 | 0.19929 |
Trending nowThis is a popular solution!
Chapter 12 Solutions
PROBABILITY & STATS FOR ENGINEERING &SCI
- The article "Effect of Granular Subbase Thickness on Airfield Pavement Structural Response" (K. Gopalakrishnan and M. Thompson, Journal of Materials in Civil Engineering, 2008:331-342) presents a study of the effect of the subbase thickness (in mm) on the amount of surface deflection caused by aircraft landing on an airport runway. Two landing gears, one simulating a Boeing 747 aircraft, and the other a Boeing 777 aircraft, were trafficked across four test sections of runway. The results are presented in the following table. Section 3 4 Boeing 747 Boeing 777 4.01 3.87 3.72 3.76 4.57 4.48 4.36 4.43 Can you conclude that the mean deflection is greater for the Boeing 777?arrow_forwardThe article "Gypsum Effect on the Aggregate Size and Geometry of Three Sodic Soils Under Reclamation" (I. Lebron, D. Suarez, and T. Yoshida, Journal of the Soil Science Society of America, 2002:92-98) reports on an experiment in which gypsum was added in various amounts to soil samples before leaching. One of the outcomes of interest was the pH of the soil. Gypsum was added in four different amounts. Three soil samples received each amount added. The pH measurements of the samples are presented in the following table. Gypsum (g/kg) pH 0.00 7.88 7.72 7.68 0.11 7.81 7.64 7.85 0.19 7.84 7.63 7.87 0.38 7.80 7.73 8.00 Can you conclude that the pH differs with the amount of gypsum added? Provide the value of the test statistic and the P-value.arrow_forwardThe article " The Ball-on-Three-Ball Test for Tensile Strength: Refined Methodology and Results for Three Hohokam Ceramic Types" (M. Beck, American Antiquity, 2002:558-569) discusses the strength of ancient ceramics. Several specimens of each of three types of ceramic were tested. The loads (in kg) required to caack the specimens are as follows: Ceramic Loads (kg) Type Sacaton 15, 30, 51, 20, 17, 19, 20, 32, 17, 15, 23, 19, 15, 18, 16, 22, 29, 15, 13, 15 27, 18, 28, 25, 55, 21, 18, 34, 23, 30, 20, 30, 31, 25, 28, 26, 17, 19, 16, 24, 19, 9, 31, 19, 27, 20, 43, 15 20, 16, 20, 36, 27, 35, 66, 15, 18, 24, 21, 30, 20, 24, Gila Plain Casa Grande 23, 21, 13, 21 Construct comparative boxplots for the three samples. b. How many outliers does each sample contain? c Comment on the features of the three samples.arrow_forward
- Mist (airborne droplets or aerosols) is generated when metal- removing fluids are used in machining operations to cool and lubricate the tool and workpiece. Mist generation is a concern to OSHA, which has recently lowered substantially the workplace standard. The article "Variables Affecting Mist Generaton from Metal Removal Fluids" (Lubrication Engr., 2002: 10-17) gave the accompanying data on x = fluid-flow velocity for a 5% soluble oil (cm/sec) and y = the extent of mist droplets having diameters smaller than 10 μm (mg/m³): x y 89 177 189 354 362 442 965 .40 .60 .48 .66 .61 .69 .99 a. The investigators performed a simple linear regres- sion analysis to relate the two variables. Does a scat- terplot of the data support this strategy? b. What proportion of observed variation in mist can be attributed to the simple linear regression relationship between velocity and mist? c. The investigators were particularly interested in the impact on mist of increasing velocity from 100 to 1000 (a…arrow_forwardAn article in the IEEE Transactions on Components, Hybrids, and Manufacturing Technology (1992, Vol. 15) describes an experiment for investigating a method for aligning optical chips onto circuit boards. The method involves placing solder bumps onto the bottom of the chip. The experiment used three solder bump sizes and three alignment methods. The response variable is alignment accuracy (in micrometers). The data are as follows: Solder Bump Size Alignment Method (diameter in um) 2 75 4.61 1.58 1.00 4.50 1.42 0.96 130 2.37 1.70 0.78 2.47 1.75 0.96 260 4.90 2.72 2.41 4.50 2.61 2.50 (a) Is there any indication that either solder bump size or alignment method affects the alignment accuracy? Is there any evidence of interaction between these factors? Use a = 0.05. The solder bump size the alignment accuracy, the alignment method the alignment accuracy, the interaction between solder size and alignment method significant in affecting alignment accuracy. (b) What recommendations would you…arrow_forwardThe decline of salmon fisheries along the Columbia River in Oregon has caused great concern among commercial and recreational fishermen. The paper 'Feeding of Predaceous Fishes on Out-Migrating Juvenile Salmonids in John Day Reservoir, Columbia River' (Trans. Amer. Fisheries Soc. (1991: 405-420) gave the accompanying data on y = maximum size of salmonids consumed by a northern squaw fish (the most abundant salmonid predator) and x = squawfish length, both in mm. Here is the computer software printout of the summary: Coefficients: Estimate Std. Error t value Pr(> |t|) (Intercept) −89.010 16.703 −5.329 0.000 Length 0.705 0.046 15.293 0.000 Using this information, give the equation of the least squares regression line.arrow_forward
- The article "Modeling of Urban Area Stop-and-Go Traffic Noise" (P. Pamanikabud and C. Tharasawatipipat, Journal of Transportation Engineering, 1999:152–159) presents measurements of traffic noise, in dBA, from 10 locations in Bangkok, Thailand. Measurements, presented in the following table, were made at each location, in both the acceleration and deceleration lanes. Location Acceleration Deceleration 78.1 78.6 78.1 80.0 3 79.6 79.3 4 81.0 79.1 78.7 78.2 78.1 78.0 78.6 78.6 78.5 78.8 78.4 78.0 10 79.6 78.4 Can you conclude that there is a difference in the mean noise levels between acceleration and deceleration lanes?arrow_forwardStructural engineers use wireless sensor networks to monitor the condition of dams and bridges. The article "Statistical Analysis of Vibration Modes of a Suspension Bridge Using Spatially Dense Wireless Sensor Network" (S. Pakzad and G. Fenves, Journal of Structural Engineering, 2009:863-872) desaribes an experiment in which accelerometers were placed on the Golden Gate Bridge for the purpose of estimating vibration modes. For 18 vertical modes, the system was underdamped (damping ratio 1)? Explain why or why not f. e. For what damping ratio would you predict a frequency of 2.0?arrow_forwardPLS ANSWERarrow_forward
- During the spring of 1999, many fuel storage facilities in Serbia were destroyed by bombing. As a result, significant quantities of oil products were spilled and burned,resulting in soil pollution. The article “Mobility of Heavy Metals Originating from Bombing of Industrial Sites” (B. Škrbić, J. Novaković, and N. Miljević, Journal of Environmental Science and Health, 2002:7–16) reports measurements of heavy metal concentrations at several industrial sites in June 1999, just after the bombing, and again in March of 2000. At the Smederevo site, on the banks of the Danube River, eight soil specimens taken in 1999 had an average lead concentration (in mg/kg) of 10.7 with a standard deviation of 3.3. Four specimens taken in 2000 had an average lead concentration of 33.8 with a standard deviation of 0.50. Find a 95% confidence interval for the increase in lead concentration between June 1999 and March 2000.arrow_forwardA study was carried out to compare the writing lifetimes of four premium brands of pens (factor A). It was thought that the writing surface (factor B) might affect lifetime, so three different surfaces were randomly selected. A writing machine was used to ensure that conditions were otherwise homogeneous (e.g., constant pressure and a fixed angle). The accompanying table shows the two lifetimes (min) obtained for each brand-surface combination. A B Brand of Pen AB Error Total 1 2 3 4 = 1 Writing Surface 707, 659 668, 685 659, 685 698, 650 5411 SS 2 713, 726 722, 740 668, 684 704, 666 5623 The hypotheses are as follows. 2=0 HOG: G² HaG: G² > 0 HOA: α₁ = α₂ = α3 = 4 = 0 HOB: 0B² = 0 HaA: at least one a, # 0 2 HaB: >0 Carry out an appropriate ANOVA. (Use a = 0.05. Round your answers to two decimal places.) Source df f 3 660, 645 692, 720 678, 750 688, 733 5566 MS XI.. 4110 4227 4124 4139 16,600 Test for an interaction. Find the critical value. (Round your answer to two decimal places.)…arrow_forwardAn engineer has set up a DOE (design-of-experiment) to test the wear of laminated materials and how it depends on the glue and filler used. At each test condition, two experiments were run. The engineer collected the data below. Calculate the main and interaction effects. Glue Filler Result 1 Result 2 0.3 0.5 65 70 0.6 0.5 0.3 0.75 0.6 0.75 101 89 97 61 72 105 Calculate the test statistics. SSclue number (rtol=0.01, atol=0.0001) SSpiller number (rtol=0.01, atol=0.0001) SSinteraction number (rtol=0.01, atol=0.0001) Felue number (rtol=0.01, atol=0.0001) Friller number (rtol=0.01, atol=0.0001) Finteraction number (rtol=0.01, atol=0.0001) Calculate the p-value. Pclue number (rtol=0.01, atol=0.0001) PFiller number (rtol=0.01, atol=0.0001) Pinteraction number (rtol=0.01, atol=0.0001) Which are statistically significant at a 10% level? State your decisions. O (a) Cannot Reject HO: Glue O (b) Reject HO: Interaction O (c) Cannot Reject HO: Interaction O (d) Reject H0: Filler O (e) Cannot Reject…arrow_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman