| Author | Lekhak, Beni Madhav |
| Call Number | AIT Thesis no. GT-86-13 |
| Subject(s) | Vibration research
Vibration research
|
| Note |
A thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | A case study was made with respect to the geotechnical
problems of ~wo ancient monuments in Lopburi, Thailand namely:
Prang Sam Yod and the leaning tower of Wat Manichulakan. The
separation· of laterite blocks, tilting, and differential
settlement in the superstructure were believed either due to
ground vibrations caused by heavy traffic on adjacent streets
and railways, or some foundation problems. A detailed
investigation was launched with a series of field and
laboratory tests. Soil samples were obtained for laboratory
tests. Standard Penetration Tests ( SPT> and Dutch Cone tests
were carried out. The present existing vibration levels were
measured and monitored by means of velocity transducers. Index
tests, consolidation tests, and cyclic triaxial laboratory
tests were carried out in the laboratory. In addition, soil
chemical tests, optical mineralogy tests by thin sections, x-ray diffraction· tests on soil specimen, and weathering
characteristics were investigated on the laterite blocks. The
results showed that the underlying soil strata consist of
highly overconsolidated stiff calcareous soil <rich in CaC03)
with intermittent layers of sand, varying from few centimeters
at Manichulakan leaning tower to a few meters at Prang Sam Yod.
The vibration induced cyclic acceleration was found to be · too
low ( 1. 5 to 3. 5 gals) to cause considerable sliding in
laterite blocks and differential settlement. However, axial
deformations of 1-1. 9% occurred in sand and clay layers and 0 . 3-
0 . 6% in case of laterite blocks under 10, 000 cycles of cyclic
triaxial floadings applied with a cyclic acceleration of 1. 8
gals to 6 . 2 gals at the rate of 6 cycles per minute. There was
no cumulative cyclic strain between two laterite blocks sliding
at the defined 45 degrees inclined plane . The geochemical and
mineralogical analysis of soil showed the presence · of cracks
a nd nodules in the calcite structure with abundancy in calcite,
quartz and montmorillonite. The weathering effects, and lack of
bonding material and tensile reinforcement at Prang Sam Yod
were much critical. Consequently; the remedial measure shifted
from geotechnical aspects to structural aspects . recommending
the insertion of deformed steel bars for reinforcement between
laterite blocks in the superstructure with epoxy grouting. |
| Year | 1987 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Geotechnical and Transportation Engineering (GT) |
| Chairperson(s) | Bergado, Dennes T. ;Towhata, Ikuo
; |
| Examination Committee(s) | Chandra, Sarvesh; |
| Scholarship Donor(s) | Government of Italy.; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1987 |
