GEOLOGICAL REASONING FOR ENGINEERING
PROTECTION OF TERRITORIES BASED ON G.S.ZOLOTAREV’S
IDEAS
I.Yu.Grigorieva
Geological faculty of the Lomonosov Moscow State University, Vorobyovy Gori, Moscow, Russia;
E-mail: ikagrig@inbox.ru
Abstract: The problems of the geological study of measures of engineering
protection of territories are discussed; contribution in addressing these issues by
outstanding engineer-geologist, professor at Moscow State University
G.S. Zolotarev. The content of regulatory documents for engineering protection in
Russia was analyzed. There are some additions that could be considered when
developing a new generation standards.
In considering issues of engineering protection of territories from natural and
man-made hazards and estimating the role and importance of engineeringgeological acquisitions in this it’s wise to apply to the vast experience accumulated
by our home researchers in engineering protection of unique and complex object.
In particular to the ideas that have been made by G.S.Zolotarev at the time.
Graduated in 1940 Moscow Geological Prospecting Institute he had been
working from 1948 to 2006 at the Geological Faculty of Lomonosov Moscow
State University. He has brought up a whole galaxy of engineering geologists
among them: G.A. Golodkovskaya, V.M. Kutepov, E.V. Kalinin, I.A. Parabuchev,
V.S. Krupoderov,
A.A. Makhorin,
O.V. Zerkal
and
many
others.
Zolotarev G.S. participated in the engineering-geological study for the construction
of several large hydraulic structures on the Volga, Kama, Dnestr, Enisey, Naryn
and Inguri. He developed a scheme of engineering protection of territories from
landslides at several sites in the Crimea, Caucasus, Central Asia and Trans-Baikal
region.
In one’s time G.S.Zolotarev was noted [2] that published and library materials
on engineering-geological study of geological processes, reasoning engineering
activities, to prevent their negative impact on the territory and various buildings are
so different in approach and views of the authors, objects and environmental
conditions that need to be based on some main terms and concepts. Many
regulatory documents such as SNiP 22-02-2003 are considering engineering
protection actions with varying details and validity but they are even in
combination are not sufficient to define the content of geological reasoning for
engineering protection of territories and claim to it.
Thus of all the natural diversity of processes in the SNiP 22-02-2003 regarded
engineering protection measures only from eleven of them: landslides, avalanches,
mudflows, rock fall, karst, flooding and water damage, processing of the coast,
frost heave, thermokarst and naled. In this case number of processes such as
erosion, suffusion, subsidence and other are not taken into account. Requirements
for geological study of engineering protection measures contained in the current
regulatory documents only under the general provisions and as the common
requirements. In the main sections of the SNiP 22-02-2003 contain information
about types of facilities and activities used for the engineering protection territories
from a dangerous process, calculation technique and technical requirements for
facilities and activities.
Currently a technogenic load on the geological environment is increasing that
dictates the need for a more detailed and qualified geological reasoning used
actions of engineering protections. Significant restrictions of SNiP 22-02-2003 on a
processes set requires their widening and developing the content of geological
reasoning for engineering protection in view of approaches developed by
G.S.Zolotarev and a number of other researchers. Analysis of the experiences
gained by engineering protection [2, 3] shows that often the causes of failures in
the activities against dangerous processes were to hold only a local or uncomplex
measures not enough depth study of nature, laws and mechanism reciprocal
geological processes and consequences of the economic activity influence.
The main tasks of engineering-geological studies [2] in dealing with
engineering protection of territory from dangerous geological processes must be:
1) The study of stratigraphy, structure, occurrence of Pliocene-Quaternary
deposits of area, the weathering crust, tectonic structures and the latest differential
movements;
2) Regional water distribution study, the hydraulic connection and the
groundwater regime, and their adaptation to separate bundles of rocks, zones of
intense fracturing and breaks;
3) The preliminary characterization of engineering-geological factors of seismic
zoning;
4) Development of regional engineering-geological classification of rocks and
developed in these phenomena, as well as to define features to estimating the
intensity of processes developed in these;
5) Reasoning the selection and initiation of sites for stationary observations for
the regimes of modern geological processes and groundwater, for water content
and condition of rocks, for technological and meteo-gidrological factors.
We proposed a technical approach [1] to develop geological reasoning actions
of engineering protection from a slope processes on the example of road AdlerKrasnaya Polyana construction site. Which can be seems as a step towards the
development of the regulatory and methodical basis of geological reasoning actions
of engineering protection against exogenous hazards. For example considering the
most of the wide-spread slope processes and landslides in particular, should be
borne in mind that the main impacts of measures against to landslides and to ensure
the stability of slopes should be directed to [2] the main factors causing them,
which despite the diversity, the difficulties of identifying and evaluating are
reduced to two groups: 1) changing the rock strength of slope (c) and 2) the force
that changes the stress and strain state of rock mass of slope and increasing the
shear stresses ().
In estimating the soils strength composing the slope it is necessary to determine
not only the values of strength properties in the natural moisture content, but also a
wide range of moisture content changes (Fig. 1). Moreover the strength indicators
should be defined for the direct and the reverse shear (Fig. 2). Underestimation of
the change in soil strength over time may lead to relevant mistakes in the
conclusions.
Fig. 1. Interdependence between the soil moisture (W) and strength ()
Fig. 2. Results of direct (1) and reverse (2) soil shear
As an example you can see the estimation of the slope stability of the r.Mzymty
Valley calculated by the method of Morgenstern-Price with the program
«GeoStudio» (Table 1). The calculation was made for a typical landslide in the
next conditions: the structure of the landslide, the properties of its constituent soils,
the effect of free leaking of the aquifer, as well as typical for the area seismic
impact. As a result of simulation showed that intensification of landslide will occur
even when the intensity of seismic impact at 6 points on a 12-point scale (similar
effects occur in the study area with a frequency of about 1 every 10 years).
With the help of the calculations also showed that with increasing soil
moisture at 5% stability factor is reduced by 20%. In this case sliding
motions occur even at the seismic impact by the intensity in 5 points.
Table 1
Variants of the slope stability calculation for the river Mzymta Valley [1]
Model taking into account the
Regulatory properties of soils
Regulatory properties of soils and the
impact of groundwater free-flow
Regulatory properties of soils, the impact
of groundwater free-flow and seismic
effect in the intensity at 6 points (40%)
Regulatory properties of soils, the impact
of groundwater free-flow and seismic
effect in the intensity at 8 points (15%)
2.722
Conclusion about
the stability of
the landslide
slope
stable
2.153
stable
1.161
unstable
0.980
unstable
Factor of
safety
Engineering-geological studies to reasoning the schemes of engineering
protection of territories must have the appropriate specificity and focus not so
much on the grain size analysis of soils, as happens often, but to estimation their
rate of weathering, water penetration, cold resisting property, erosion properties
etc. In other words investigations should be focused to evaluate the soil properties,
which are lost its importance in engineering-geological survey now, but are
paramount importance in the analysis of the intensity and speed of development of
geological processes.
Unfortunately to date the system engineering-geological research has not found
a proper use a practice of paleoreconstruction river valleys and making schemes of
the slopes valley. Such schemes (Fig. 3) are used to recover the course of the
developing valley, follow the main trends in their evolution and to identify
geologically significant areas in which priority must be implementation of
measures of engineering protection.
Fig. 3. Paleoreconstruction of developing river Dnestr Valley
Its own specific features to reasoning the schemes of engineering protection
should be studying the hydraulic connection and the groundwater regime. Showing
up laws should be reflected in appropriate schemes (Fig. 4) which should specify
the way of the groundwater flow.
Fig. 4. The scheme of Pliocene-Quaternary deposits of Dnestr Valley
Essential to reasoning the schemes of engineering protection should have a
record interrelation and interdependence of the developed processes.
Implementation of engineering protection measures should take into account the
identified relationships and make as small as possible changes in existing
processes. Often excessive use of a large number of expensive and bulky design
solutions entails the development of new no less dangerous processes. A striking
example is the engineering protection of the Black Sea coast in the area of AdlerSochi, where construction a lot of sea walls and concrete lining the shore prevented
abrasion shore but caused a disruption of normal circulation of longshore currents,
and as a consequence - the stagnation of water and essential contamination.
The present level of GIS technology development helps to create permanent
models of the situation on the protected area of land. Adequacy of functioning as
such models will be primarily determined by the nature and completeness of the
data embedded in them. Here it is appropriate to recall the rich heritage which has
been incorporated into the works of many of the founders of engineering geology
such as the G.S. Zolotarev.
References
1. Grigorieva I.Yu., Kushman M.V. Reasoning engineering protection of the territory from slope
processes for projected railway Adler-Krasnaya Polyana/ Georisk. March 2009. p. 28-39 (in Russian).
2. Zolotarev G.S. Engineering Geodynamics. - Moscow: Moscow State University, 1983. – 328 p.
(in Russian).
3. Zolotarev G.S., etc. Engineering protection of territories and objects against dangerous
geological processes. M: «Geoinformmark», 1994. – 69 p. (in Russian)
4. SNiP 22-02-2003. Engineering protection of territories, buildings and structures from
dangerous geological processes. Summary. M. Rosstroy, 2004. - 39 p. (in Russian)