d.tunnel: Properties of concrete in a tunnel

In qmrobust: Quality Management: Examples from the concrete industry

Description

Samples of concrete used in the construction of an opencast tunnel are obtained and several properties are measured. Two boreholes of different depths are taken at the same 20 positions. This leads to two datasets.

Usage

data("d.tunnel1"); data("d.tunnel2")

Format

Two data frames with 240 and 412 observations, respectively, on the following variables.

section

Section of the tunnel profile, with levels d.1 and d.2 for decks 1 and 2, and w.1 and w.2 for walls 1 and 2

diameter

Diameter of bore hole, 68mm for d.tunnel1 and 50mm for d.tunnel2

n

Number of ...???

position

Position, factor with levels A to V

layer

Layer, factor with levels layer.1: ..., layer.2: ..., layer.3: ..., d.tunnel1 only contains the first 3 layers

strength

Compressive strength of the concrete [MPa]

density

Density []

perm.O2

Permeability for oxigen ???[m2] (only d.tunnel1)

cond.CL

??? (only d.tunnel1)

pores.total

Pores [m2] (only d.tunnel2)

pores.air

Pores for air [m2] (only d.tunnel2)

pores.H2O

Pores for water [m2] (only d.tunnel2)

water

??? (only d.tunnel2)

cond.H2O

??? (only d.tunnel2)

Details

The samples for the two datasets are bore kernels of 68 and 50 mm diameter, respectively. The samples with the same position and layer are taken near each other.

Source

Leemann, A., Hoffmann, C., Malioka, V. and Faber, M. (2006). Variability of concrete properties in structures, Technical Report 611, Bundesamt f\:ur Strassen (ASTRA), Bern, Switzerland.

References

Stahel, W.A., Moro F. and Luco, L.F. (2015). “Statistical Procedures for Performance-based Specification and Testing”. In:

Examples

data(d.tunnel1)
showd(d.tunnel1)
data(d.tunnel2)
showd(d.tunnel2)

## merge
d.tunnel <- merge(d.tunnel1, d.tunnel2,
  by=c("section","position","layer"), all.x=TRUE,
suffixes=c(".68",".50"))

## compare densities in neighboring boreholes
plot(density.50~density.68,d.tunnel)

## regression model to explain  permeability
r.lm <- lm(log10(pmax(1e-11,perm.O2))~log10(pmax(cond.CL,0.5))+
             density.68+section,  data=d.tunnel)
summary(r.lm)
plot(r.lm)

qmrobust documentation built on May 2, 2019, 6:50 p.m.