| Abstract | Poboljšanje inženjerskih svojstava glinenih tala može se postići djelovanjem
koncentriranih eksplozivnih punjenja odnosno primjenom metode zbijanja koherentnih tla
miniranjem. Detonacija koncentriranog eksplozivnog punjenja u tlu generira udarni val koji je
podržan ekspanzijom produkata eksplozije te u tlu stvara intenzivan porni predtlak i oscilacije
u okolini eksplozivnog punjenja. Pri tome se razara prirodna struktura glinenog tla, postiže se
značajno povećanje zapremnine bušotine, odnosno generira se kuglasto proširenje, te se u
susjednom području glineno tlo značajno stlačuje, a njegova gustoća povećava.
Eksplozijom nastali slobodni volumen služi za smještaj injekcijske mase i geotehničkog
sidra, sa svrhom stvaranja mehaničke i adhezijske veze okolnog glinenog tla i injekcijske
mase. Čvrstoća ostvarene veze uz ostalo ovisi o volumenu proširenja i o koeficijentu
zbijenosti.
Mjera uspješnosti izvedenih miniranja je volumen generiranog proširenja. Volumen
proširenja i svojstva zbijenog glinenog tla moguće je odrediti terenskim i laboratorijskim
metodama.
U tu svrhu je razvijen sustav opažanja, mjerenja i računanja oblika i zapremnine nastalog
proširenja. Sustav uključuje instrumentalni i programski dio, gdje je osmišljena aplikacija
koja uz izračun koordinata bušotina omogućuje i detaljnu grafičku interpretaciju proširenja u
2D i 3D prikazu.
Primjenom standardnih terenskih i laboratorijskih metoda moguće je odrediti promjene u
tlačnoj čvrstoći, posmičnoj čvrstoći, gustoći te modulu elastičnosti u tlu nakon miniranja. Ta
ispitivanja omogućavaju određivanje mjere poboljšanja svojstava tla u ovisnosti o
detonacijskim parametrima, masi i vrsti eksploziva.
Prema tome, uz određivanje utjecaja navedenih parametara miniranja na oblik i
zapremninu miniranjem izvedenog proširenja u radu su predložene i smjernice za odabir
parametara miniranja prema traženim svojstvima okolnog, na taj način poboljšanog tla, a u
skladu sa zahtjevima na sidrenje konkretne strukture, primjerice kosina glinenih tla u
geotehničkoj praksi. |
| Abstract (english) | Improvement of engineer properties of clay soils can be achieved by the action of the
concentrated explosive charge or by applying a blasting method in the coherent soil.
Detonation of the concentrated explosive charge in the clay soil generates a shock wave
supported by the expanding explosion product that creates intense strong pore excess pressure
and oscillations in the surrounding area of the explosive charge. In that case, the natural
structure of the clay soil is destroyed, a significant increase in the borehole volume is
achieved, the spherical cavity is generated, and in the adjacent area the clay soil is
significantly compressed and its density increases.
With the detonation of the generated shock wave in the soil, the released energy creates a
strong pore excess pressure and intense vibrations in the surrounding area of explosive
charge. During this process, the natural structure of the clay soil is destroyed, cavities are
created near the explosive charge, and in the zone along the wall, there is an intense
compression of clay soil with an increasing density.
The efficiency rate of conducted blasting is a volume of the resulting expansion. The
expansion volume and the compaction of the clay soil can be determined by field and
laboratory research.
For this purpose, the system of observation, measurement, and calculation of the shape and
volume of the resulting cavity is being developed. The system includes an instrumental and
programming part, where a designed application enables detailed graphical interpretation of
the cavity in 2D and 3D views, along with the borehole coordinate calculations.
This system represents the integration of RTK GNSS, Heavy Duty GeoVision Borehole
Camera and Laser (EDS-C). For calculating the generated cavity and its volume at a certain
depth of recording, an application "Bušotine" was created.
Field researches and innovations in field data processing resulted in a sufficient amount of
quality data that enabled the development of this type of application.
The significance and contribution of the application "Bušotine" are reflected on the one
hand in the use of open source technology, and secondly in commercial utility compatibility
and the ability to connect to other systems through a series of interfaces. The added value of
an application is achieved through the use of web technology, enabling secure login to the
system from any computer, tablet, cell phone or other similar device connected to the Internet.
All the information that users collect and enter into the system are immediately available to
all remaining process parts.
The concept and possibilities of the application in the technical field are innovativeness.
Aside from the application's calculation of the coordinates and the generated cavity and its
volume, the application gives a detailed graphical interpretation of the 2D and 3D view of the
resulting cavity. Also, the compatibility of the application with other CAD tools will greatly
contribute to a check and a more detailed 3D cavity view.
The use of the standard field and laboratory methods will determine changes in the
compressive strength, shear strength, density and elasticity modulus in the clay soil after
blasting. This research will enable the determination the improvement of the soil properties
depending on the detonation parameters, quantity, and type of explosives.
Accordingly, with the determination of the influence of the above-mentioned blasting
parameters on the shape and volume of the implemented extension in the doctoral
dissertation, suggestions will be proposed for selecting the blasting parameters according to
the required properties of the surrounding clay soil improved in accordance with the
requirements for anchoring the concrete soil structure in geotechnical practice. |
