Your Tunnelling Assistant
Giving Air Cover to Tunnelling by Code
A Personal Cloud Computing Initiative by Dr. C.W. Boon
(CEng MICE, MIEAust CPEng, e-mail: chiaweng.boon@oxfordalumni.org)
©
BATS-2BCW: Building Assessment using Tensile Strains - based on Burland Boscardin Cording Wroth for tunnelling - ver 4c
User Guide:
Download PDF (BATS_ver4b)
Educational video:
SYTA 2021 - CWBoon
Near edge
Far edge
Building length (m)
Building height (m)
Building distance from ref. line (m)
Predicted vertical ground settlement (mm)
0
0
Predicted horizontal ground movement (mm)
0
0
Northbound
Southbound
Volume loss (%)
Soil constant, k
Tunnel external diameter (m)
Depth to tunnel axis, z (m)
Distance of tunnel axis to ref. line (m)
The ref. line is the centreline (midway) between the two tunnel axes. Both twin tunnels are assumed to be at the same offset distance from the ref. line, but opposite signs.
Hogging zone - neutral axis at lower edge. Span of building in hogging zone (m):
Refer to assumptions on the generation of damage charts.
Sagging zone - neutral axis at centreline. Span of building in sagging zone (m):
Refer to assumptions on the generation of damage charts.
Position of point of inflection (m)
Predicted horizontal movement at point of inflection (mm)
Predicted settlement at point of inflection (m)
Deflection of building in sagging zone (mm)
Deflection of building in hogging zone (mm)
Deflection ratio of building in sagging zone (%)
Deflection ratio of building in hogging zone (%)
Horizontal strain of building in sagging zone (%)
Horizontal strain of building in hogging zone (%)
Bending strain in sagging zone (%)
Bending strain in hogging zone (%)
Diagonal strain in sagging zone (%)
Diagonal strain in hogging zone (%)
Maximum tensile strain in sagging zone (%)
Maximum tensile strain in hogging zone (%)
Assumptions:
E/G = 2.6
Contours in damage chart are generated using length,
L
, and height,
H
, of the original building dimensions
The actual partitioning of sagging and hogging spans are considered in the calculation of deflections
The underlined "Maximum tensile strain" above for each hoggging and sagging zones can be used to check against the "Damage Category" below, based on partitioned hogging and sagging lengths of the building.
Damage Category for Masonry Buildings (after Burland et al., 1977 and Boscardin & Cording, 1989)
Category of Damage
Normal Degree of Severity
Limiting Tensile Strain (%)
0
Negligible
0.0-0.05
1
Very Slight
0.05-0.075
2
Slight
0.075-0.15
3
Moderate
0.15-0.3
4
Severe to Very Severe
> 0.3
For inquiries/bug reports, please contact:
Email:
chiaweng.boon@oxfordalumni.org
Recognitions:
International Society for Rock Mechanics and Rock Engineering (ISRM):
https://isrm.net/page/show/137?tab=288
American Rock Mechanics Association (ARMA):
https://armarocks.org/sample-page/future-leaders/
Malaysian Representative for the International Tunnelling Association Young Member Group (ITAym)
Disclaimer:
User's discretion required. Trial version. This is for educational purposes, and not to be used outside its intended purpose.
If you wish to introduce changes for your own purpose, e.g. E/G, L/H for damage chart, or the position of neutral axis, please kindly send me an email.