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INNOVATIVE SOLUTIONS IN
GEOTECHNICAL ENGINEERING

STABILITY AND EARTHQUAKE RESISTANT ENGINEERING STRUCTURES

Earthquake resistant foundation
stability structures

For the earthquake-resistant stability constructions, the difference in supporting stability potential by using the new approach is over 30-50%. Unfortunately for these constructions, it bears a negative sign; it is therefore necessary and urgent to revise the eartquake-resistant regulatory procedure for laying the foundations of buildings.

A conventional earthquake-resistive design method may include a pseudo-static analysis, or dynamic analysis, wherein the latter may include a response at which an earthquake-resistive matches an external vibration-force. The conventional earthquake-resistive design method may not provide an exact earthquake force, that needs to be balanced with an amount of a resistive force of a horizontal connecting surface arranged between a foundation and a building structure.

As shown by the pictures of the recent earthquake events in Turkey and Taiwan, the collapse of most of the mostly shallow-founded structures was caused in most cases by the yielding of the foundation or the yielding of the resistive of the structural connection of the structure to the foundation. Both are the result of an unsubstantiated earthquake force. Buildings that have collapsed and have not been demonstrated to be stable with the added effect of kinetic forces from the earthquake could have occurred even with compliance with current regulations, because the regulations do not require "primary" proof of the impact of kinetic forces or "mechanical impedance". All previous evidentiary procedures have a secondary character because their approximation to the real state of equilibrium is indirect. In the case of earthquake-resistant various basic building structures, there is a large difference in a dimensioned earthquake force compared to previous calculations, that it is a sufficient cause of global earthquake disasters.

Thus, the conventional earthquake-resistance design method may not provide an exact earthquake resistance of the building structure.

Laying the foundation on insufficiently
load-bearing soil

Regarding the basic piling construction, the real values of its constructive parameters can finally be proven, which bear a positive sign in terms of stability potential by using the said approach. This also confirms the ancient value of the said construction.

Laying the foundation on insufficiently load-bearing soil has already been solved in ancient times by the construction collectively named "piling", implying aggregate action, or resistance. Thomas Whitaker (1976) said, "Piling is a form of construction of great antiquity, and an almost instinctive trust in piles for overcoming difficulties runs throughout foundation work".

To this day (2024), "piling" does not have a better purposeful alternative, and the alternative "is not even necessary", because, at the same time, it is the best eathquake-resistant construction. The said building construction has not been represented with a primary structural approach so far.

In most cases, it is unnecessary and irrational, and in terms of earthquakes also harmful, to search for a deep load-bearing layer using "piers or caissons" as a substitute for "piling", unless liquefaction is present.

Retaining engineering structure

Unlike first two procedures, the third one, the Retaining Engineering Structure or RES, EP 3827133, thanks to the discovered stability potential being over 30-50%, but with a positive sign, is already in practical application and implementation, and has references.

The excavation stability in water-bearing and a not water-bearing soil has so far been solved according to the least resistance principle in seeking solutions, so that the horizontal action is stabilized by horizontal "long" anchors, or heavy gravity walls, or disruptive supports. Neither can be considered an engineering solution due to the obvious spatial awkwardness in dimensions, weight, and reactive stability adverse activity.

The new solution applied by us, the new "Retaining Engineering Structure" construction (European patent, EP 3827133) eliminates anchors and gravity walls. It is introduced into the regular construction practice.

Laying the foundation on sloping
or landslide-prone terrain

Laying the foundation on sloping, or landslide-prone terrain, has so far been solved similarly as the excavation stability, with inevitable harmful consequences. The new construction, "Retaining Engineering Structure", simultaneously solves the foundation stability, and earthquake-resistant action. Such a stable combination is impossible to achieve with any other construction. This solution is particularly relevant for infrastructure facilities – roads and railways, which, in natural conditions of increased landslide instability, require the upgrade of basic solutions.

RETAINING ENGINEERING STRUCTURE

By installing batter piles at an optimum angle of 15° to 20° coupled with the vertical structures of the retaining walls, several useful advantages are achieved. The structures used so far, because of their horizontal dimension, are difficult to adapt to adjacent spaces and structures. According to the new solution, the horizontal anchor is replaced with a batter pile, which reduces the horizontal dimension of the structure by 3 to 5 times and because of the interactive effect an excess of useful structural stability potential is created, therefore increasing the safety by 1.2 to 1.25 times. Stability analysis procedure, as well as the results of the already performed test structures, confirm the above.