2645
Innovative solutions in the field of geotechnical construction and coastal
geotechnical engineering under difficult engineering-geological conditions
of Ukraine
Solutions innovantes dans le domaine de la construction géotechnique et de la géotechnique
côtière dans des conditions géotechniques complexes en Ukraine
Zotsenko M., Vynnykov Y.
Poltava National Technical University, Poltava, Ukraine
Doubrovsky M., Oganesyan V.
Odessa National Maritime University, Odessa
Shokarev V.
State Research Institute of Building Constructions, Zaporog'e, Ukraine
Syedin V., Shapoval
Academy of Civil Engineering and Architecture, Dnipropetrovs'k, Ukraine
Poizner M.
ChernomorNllproekt, Odessa, Ukraine
Krysan V.
1
, Meshcheryakov G.
2
1
"RemBud", Dnipropetrovs'k, Ukraine ;
2
Engineering Center Transzvuk, Odessa, Ukraine
ABSTRACT: This paper contains the research findings of reinforced soil cement properties manufactured by drilling mixing method.
Application of soil cement for solution of specific geotechnical problems is considered herein in terms of specific examples In the
field of coastal geotechnical engineering the hybrid coastal hydraulic engineering structures and sheet pilings using reinforced
concrete semi-shells have been developed. Full-scale physical simulation of pressing-in and removal of steel piles is carried out using
a modular coordination pile-pressing system.
RÉSUMÉ : Cet article présente les résultats de l’étude des caractéristiques de matériau renforcé sol-ciment fabriqué par forage et
mélange en place. L’utilisation de mélange sol-ciment pour la résolution de certains problèmes géotechniques est considéré à partir
d’exemples précis. Dans le domaine de la géotechnique côtière, des ouvrages mixtes côtiers et maritimes ont été construits, ainsi que
des pieux à rainures, fabriqués en utilisant des demies coques en béton armé. La simulation physique à grande échelle des processus
d’enfoncement et d’extraction des pieux en acier est réalisée par application d’un système de coordination modulaire d’enfoncement
des pieux.
KEYWORDS: soil cement, drilled pile, roll displacement of buildings, pile-pressing system.
1 DRILLED PILES IN UNSTABLE SOILS
Drilled piles installation in unstable soils is specified by
conditions to secure wellbore stability prior to concrete placing.
We know some well-drilling methods in such soils under
protection of well casing being removed at concrete placing or
under drilling mud protection followed by underwater
concreting. SOLETANCHE METHOD of drilled piles
installation is now very much in evidence as well. It involves
the cored screw dipping into the soil to the projected drilling
depth and feeding of concrete mixture through such screw under
pressure with simultaneous screw lifting.
However the aforesaid methods have their faults,
specifically:
application of well casings results in considerable increasing
of works costs, and in some cases it’s not possible to
remove well casings. Moreover floated soil may escape
from drill hole into the well casing thus damaging
neighboring buildings and constructions;
the way to install reinforcement cage into the piles
manufactured by SOLETANCHE technology seems rather
problematic, whereas drifting sand penetration to the drill
hole at drilling is not improbable;
drilling under the drilling mud and underwater concreting
prevents floated soil escaping into the well casing, but on
the other hand, makes material quality control more
complicated and increases labor intensity.
Mixed technology of drilled piles manufacturing provides
primarily manufacturing of soil-cement elements (SCE) with
dia. 0.8-1.2 m using drilling mixing method or jet method (Van
Impe 2005, Bruce 2000, Larsson 2003). As soon as the soil
concrete reaches 30% of its rated capacity, a well hole shall be
drilled along the element’s center line up to the projected
drilling depth, so that the width of a soil concrete shell around it
amounted to 150 mm. It serves to protect a drill hole against
ingress of water and/or unstable soil for a specific period.
Reinforcement cage is mounted in a dry drill hole and the
concreting is performed.
The soil cement shells also provide increasing of bearing
capacity of composite drilled piles at vertical and horizontal
load actions owing to SCE which provide the contact surface
between a pile and the soil.
The development works for manufacturing of 8 meter long
composite drilled piles were carried out in conditions of
bedding of water-saturated loess clay soils.
The following factors were determined in process of the
research conducted:
prism strength and concrete content in soil cement in the
samples taken from the pile shaft after 28 days of concrete
damp curing (
, mPa),
SCE diameter (D, mm),
drill well cross section in SCE (D´, mm),
availability of loose soil cement in drill hole bottom
drill hole water flow 2 hours prior to surveillance (h, mm),
