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Hiscs - LMK PT System, 16, Kifissias Avenue, Athens (2025)

22/01/2025

INSPECTION & EVALUATION OF VILLAS AT KFUPM-KSA

HiSCS is involved in the evaluation and reporting regarding the structural assessment of 90 villas combos located in King Fahad University of Petroleum & Minerals (KFUPM) in the city of Dammam, Kingdom of Saudi Arabia.
KFUPM is a research University ranked among the most prestigious academic institutions in the Kingdom of Saudi Arabia.
HiSCS will provide inspection software to the local inspectors gathering all data required for the evaluation of the actual condition of the structural elements of the villas, such as foundations, columns, walls, ceiling etc.
The inspection will be flourished with Non-Destructive Testing (NDT) such as Schmidt hammer testing, ultrasonic surveys, half-cell potential tests, chemical analysis on concrete, carbonation, and concrete cores to record the compressive strength.
The evaluation will depict the structural health of the villas and define the condition rating from good to fail as well as the repair and maintenance work and priorities needed.

16/01/2025

HiSCS celebrated New Year 2025 by cutting the Vasilopita. Vasilopita is a sweet cake, symbol of the New Year associated with the feast of Saint Basil, from whom it takes its name.
Following the tradition, a coin was placed inside the cake, which whoever finds when sharing Vasilopita will be the lucky and favored one of the New Year.
Congratulations to Nefeli who found the coin. Warm wishes for a prosperous and peaceful 2025.

19/12/2024

Inspection of Bearings - Akrotiri archaeological shelter - Santorini island - Greece

Our inspectors performed the routine inspection of the spherical bearings, which support the steel shelter, of the Akrotiri Archaeological site, in Santorini Island, in Greece. The site comprises an entire coastal city, of the Minoan civilization, with streets, squares, multistory buildings, workshops, etc. preserved by the volcanic ash of the Theran eruption, which occurred in the 16th century BC.

The ninety-four (94) fixed type spherical steel bearings, located at the footings of the steel columns, have a convex curved element, which slide on a matching concave surface, transferring vertical and horizontal forces while, at the same time, allowing significant rotations in all axes. They have vertical capacity of 1500KN, horizontal capacity of 800KN and rotational capacity of ±2.5˚. Also, twenty-eight (28) of them are designed to bear up-lift loads to the order of 1100KN.

The Inspectors of HiSCS gathered all necessary data to observe the bearing’s functionality and evaluate their condition, aiming to reveal needed actions for maintenance and repair. Our special inspection software was utilized and hence all site data were uploaded, in real time, for back-office analysis and conclusions.

We welcome the initiative of the Owner, the Archeological Society of Athens, to proceed with the inspection of the bearings, thus, protecting the public investment by the timely identification of potential future issues.

04/12/2024

Installation of Seismic Isolation Bearings in Building

HiSCS’s Engineers & Technicians executed the installation of anti-seismic High Damping Rubber Bearings (HDRB), at a private residential building construction site, located in Athens, Greece. In total ten (10) HDRB bearings and one Free Sliding Pot Bearing were installed, following a methodology designed by HiSCS, to assure the prompt installation of these devices, in line with the construction requirements and the building design codes.
The seismic isolation bearings, installed on the top of the basement columns, are capable to bear a maximum vertical seismic load of 3180KN each, with horizontal movement capacity of ±250mm. The pot bearing, installed in the elevator’s shaft, is capable to bear a maximum vertical load of 2320KN, with horizontal sliding capacity in all directions of ±250mm.
Seismic base isolation is one of the most popular means of protecting a structure against earthquake forces. The fundamental principle of a base isolation system is to alter the response of the building structure so that the ground below can move “independently” without transmitting these motion forces to the building above. This is achieved by the deformation of the bearing’s rubber, which, in the case of using HDRB bearings, has a considerable damping capacity (about 15% equivalent viscous damping at 100% shear strain). During an earthquake event, the superstructure (floors), is isolated from the substructure (basement columns) that is resting on.

01/11/2024

Bridge maintenance – Elastomeric Expansion joints replacement

We have completed the selective replacement of six elastomeric expansion joint mats, located in several places on a bridge deck, responding to local authority’s concerns to ensure public safety and mitigate possible risks.

The applied expansion joint mats were carefully selected to match the geometry and the movement capacity of the initial ones, according to the initial bridge design guidelines.

23/10/2024

Highway signs inspection – Evaluation of retroreflectivity values with state-of-the-art equipment

HiSCS’s inspectors executed the inspection of 12 overhead gantries, gantry butterfly signs, and informatory signs of a highway close to Athens, Greece.

In total, more than 30 different highway signs were thoroughly inspected. The inspection recorded structural concrete and steel elements, the condition of the membranes and the overall condition of the overhead gantries. Furthermore, the retroreflectivity of the sign membranes was measured, using state-of-the-art equipment.

The inspection lasted several days, considering the sensitive matter of the minimum annoyance of highway operation, which had to be secured by the inspection teams.

A detailed inspection and evaluation report with classifications, ratings and maintenance proposals was delivered to the operator.

30/08/2024

“Smart Bridges” Project – Installation of RTSHM equipment.

HiSCS has undertaken the overall project management related with the survey & inspection, as well as the onsite installation coordination of Real Time Structural Health Monitoring (RTSHM) equipment for several road and railway bridges, spread all over Greece.

The project involves the installation of optical fiber sensors, accelerometers, thermometers, rain & water level sensors, cabling, and 5G cellular equipment, at 150 road and 100 railway bridges. The whole setup is powered through a system consisted of solar panels, batteries and charging controllers, leading to a fully autonomous configuration. The acquired data are transferred, in real time, to a platform through which they are introduced in state-of-the-art software platforms to model, analyse and monitor each bridge’s behaviour under structural loads.

This project, under the auspices of Greek Ministry of Public Works and the Technical Chamber of Greece, will initiate the early prediction of structural failures, by allowing the Authorities to take immediate decisions and measures, while at the same time save and secure the needed resources by prioritizing maintenance and repairs, where required, considering the effects of climate-related risks.

HiSCS is proud to participate in this project contributing to the transformation of the Nation's aging bridges, most of which were built between the 1950s and 1980s, into "smart" ones with real-time assessment of their structural and functional adequacy.

06/06/2024

European Technical Assessment Document (ETA) for LMK External Post Tensioning Kit

We are happy to announce LMK external post tensioning system accreditation with ETA.
We welcome our new ETA member in LMK family.

04/06/2024

Inspection of Athens Int’l Airport, access bridges

HiSCS bridge inspectors accomplished the routine inspection of the access bridges, located in El. Venizelos Int’l Airport (NAIA) in Athens, Greece.
In total, 5 road bridges and 2 aircraft bridges were thoroughly inspected. The inspection did record the overall condition of structural elements, above and on traffic, such as concrete and steel elements, bearings, expansion joints, utilities, pavements, safety features etc.
The inspection lasted more than a month, with day and night shifts, considering the sensitive matter of the minimum annoyance of airport operation, which had to be secured by the inspection teams.
A detailed inspection and evaluation report with classifications, ratings and maintenance proposals was delivered to the NAIA operator.

08/02/2024

Calatrava Stayed Cable Bridge – Special Inspection & Maintenance

HiSCS bridge inspectors and technicians, together with the stayed cable manufacturer’s specialist, accomplished the detailed inspection of the cables and anchorages of the pedestrian stayed cable bridge, located in Athens, Greece commonly known as “HARP BRIDGE” or Calatrava bridge – a name adopted from the Architect Santiago Calatrava who designed this impressive footbridge. The shape of the bridge looks like an harp inspired by the ancient Greek monuments and sculptures of the Classical Era.

What makes this bridge one of its kind is the arrangement of the cable-stay back span. In an asymmetric cable-stay bridge, where the main span is longer than the back-span, the back-span cables are generally anchored to the ground to provide the necessary stability. In most such bridges, the back-span cables are angled so that they provide a horizontal force, helping the bridge’s mast to resist the horizontal pull from the main-span cables. On this specific bridge, the two back-span cables are vertical, resisting none of the sideways pull from the main span. Instead, that pull is absorbed through the curvature of the pylon, as a compressive thrust.

The inspection took place at the anchorages of the two (2) vertical and the fourteen (14) angles high strength steel wire cables by which the steel deck (94m walkway of about 6m width) is suspended from the main curved pillar (50m height).

This type of inspection is considered as a special inspection in line with the remarks and proposals of the overall bridge routine inspection and evaluation.

A telescopic crane was used to access the anchorages located on the vertical pylon.

Anchorage’s body units were partially disassembled and cleaned so as the inspectors are able to collect information regarding their condition and evaluate their structural integrity.

HiSCS adopted a special laser device to remove superficial oxidation, restoring the rusted areas of the anchorages body. New-end cables protective cover has been designed and installed by HiSCS for further evaluation and testing. A detailed inspection and evaluation report with classifications, ratings and maintenance proposals was delivered to the bridge operator.

05/01/2024

Bridge Bearing replacement - Single pier jacking & lifting at Athens International Airport El. Venizelos, Greece

HiSCS Engineers & Technicians successfully accomplished another jacking & lifting, at the main terminal bridge of Athens Int’l Airport El. Venizelos in Greece.
The routine inspection of this bearing revealed extreme bulging and broad debonding phenomena in the elastomer, depicting its deficiency to bear loads and movements, thus the need of its replacement.
Six (6) hydraulic jacks, with lifting capacity 250 tons each, connected in parallel with a hydraulic pump, were used to lift the superstructure (max 15mm), remove the existing bearing, and replace it with the new one. Moreover, construction of new plinths took place, as well as repair of contact surfaces between bearing and superstructure.
The rubber bearing that was installed, was a non-anchored elastomer bearing, formed by layers of rubber and steel plates (reinforcement), factory bonded (vulcanized), with a diameter of 800mm, height of 309mm, weighting more than 400 kg.
The effort required to replace a bearing weighting more than 400kg in a very narrow area (max 15mm lifting), with deck opened to traffic, imposed another challenge on our team which successfully completed the task, following all safety precautions and requirements.
HiSCS studied and designed the jacking & lifting methodology, provided the equipment (hydraulic jacks, pumps, hoses, gauges, distribution plates etc.) and coordinated all onsite works.

14/12/2023

Jacking & lifting of Mall for Seismic Isolation Bearings Replacement

The Mall of Cyprus is the first shopping mall of its kind in Cyprus and has become a landmark since its first day of operation, September of 2007.
The building consists of two commercial levels – ground floor and 1st floor – with two extra supportive levels – basement and mezzanine floor.
HiSCS has been involved in the jacking and lifting operations to replace the seismic isolation bearings located on the columns supporting the building.
The existing bearings were elastomeric isolators, made of High Damping Rubber known as HDRB, shielding the superstructure from seismic forces.
Two specially designed steel temporary supports were installed, close to the columns, to place the jacking system (hydraulic jacks) since there was no area close to the bearings.
Five bearings were replaced, in total, by lifting the slab up to 15mm, removing the old bearings and replacing them with the new ones. The new anti-seismic devices are of the same type with the old ones and their isolation characteristics adhere to the relevant design.
MEP networks such as ventilations, electrical and firefighting systems were closely monitored during lifting to avoid any damages/malfunctions.
Hydraulic pressure vs lifting load, lifting elevations and jacks’ piston extraction were constantly monitored during the process, to ensure the proper ex*****on and to observe the structural behaviour of the building.
Works were accomplished in line with the approved methodology, within a very tight schedule. The replacement of the seismic isolators had to be carried out one by one, with jacking system and temporary supports being moved to the next position at the earliest, avoiding any disturbance to the busy operation of the Mall.

13/11/2023

Bridge Bearing replacement at Athens International Airport El. Venizelos, Greece

HiSCS Engineers & Technicians successfully accomplished the Jacking & lifting, of the main terminal bridge of Athens Int’l Airport El. Venizelos in Greece.
The bridge, which was designed and erected between 1999 & 2001, serves as the main access to the departure hall of the airport. It has the form of a prestressed solid slab with voids, and it is composed of a complex of ramps, whose width ranges from 7.7m to 32m.
The routine inspection of the bearing revealed extensive punctures, extreme bulging and debonding phenomena in the elastomer, depicting its deficiency to bear loads and movements, thus the need of its replacement.
Four (4) hydraulic jacks, with a total lifting capacity of 1000 tons, connected in parallel with a hydraulic pump, were used to lift the superstructure (max 15mm), remove the existing bearing and replace it with the new one. Moreover, construction of new plinths took place, as well as repair of contact surfaces between bearing and superstructure.
The rubber bearing that was installed, was a non-anchored elastomer bearing, formed by layers of rubber and steel plates (reinforcement), factory bonded (vulcanized), and it had a diameter of 450mm and height of 189mm.
HiSCS studied and designed the jacking & lifting methodology, provided the equipment (hydraulic jacks, pumps, hoses, gauges, distribution plates etc.) and coordinated the onsite works of the bearing replacement following all safety precautions and requirements.

06/09/2023

Lifting & Jacking of Oil Terminal Jetty – Bearings Replacement

The jacking and lifting works to replace the structural bearings supporting the steel pipe racks of an oil terminal jetty located in Cyprus have been accomplished by HiSCS.
Marine oil terminals jetties are storage depots for oil, fuels, and petrochemical products providing a deep water mooring for tankers. Jetties have loading/unloading arms and pipe racks for transferring petrochemicals to/from ships to shore storage tanks.
The jetties are designed to withstand the petrochemical cargo loads, wind, seismic and vessel accidental collisions.
The multi-span steel trestle is located on pile caps and is supported on bearings of several types including viscous dampers.
An accidental detachment of two existing bearings from the steel superstructure has been revealed during the routine inspection.
More precisely, the upper anchoring steel plates of bearings had been shifted (failure of mechanical anchoring with the steel superstructure) jeopardizing the proper transfer of service and seismic loads.
Two (2) hydraulic jacks of lifting capacity 390tons each, connected in parallel with a hydraulic pump were used to lift the superstructure in order to remove the existing bearings and replace them with new.
HiSCS studied and designed the lifting methodology by providing the hydraulic equipment (jacks, pumps, hoses, gauges, distribution plates etc.) coordinating the site as well works of the lifting, jacking and bearings replacement.
HiSCS Engineers & Technicians successfully accomplished the works in a very demanding environment following all safety precautions and requirements of the petrochemical facility.

03/08/2023

We are happy to inform you that from now on you can also Follow us on Instgram: https://www.instagram.com/hiscslmk/

02/08/2023

Jacking & Lifting of Silo Roof for Bearings Replacement

HiSCS has commenced the jacking and lifting works to replace the bearings supporting the steel roof of a silo clinker located in Vassilikos area in Cyprus.
The initial installation of bearings took place circa 2007. The existing bearings are steel spherical fixed type with anti-lifting capacity.
The bearings support the circular roof consists of central beams in the radial direction (34 pcs) connected with IPE beams in the circumferential direction of concentric circles. All 38 bearings are installed on the silo’s perimeter wall made of reinforced concrete.
Following the routine inspection, the bearings have been found with defects such as anchoring failures and excessive misalignment – speculations – due to accidental silo overfilling and loads transferred to the roof from the stored material.
The new lifting design foresees the replacement of all 38 bearings by jacking and lifting of silo roof using hydraulic jacks.
The jacking and lifting are performed partially in groups of 2-3 consecutive bearings, using 2 jacks of 300tons capacity each, connected in parallel with a hydraulic pump.
Lifting of no more than 10mm was sufficient to remove the existing bearings and replace them with the new ones.
The new bearings are of the same type but with improved characteristics (higher vertical-horizontal and uplift load capacity). In addition, they allow small movements in both horizontal directions prior of their locking up to bear the horizontal loads and have higher rotational capacity.
HiSCS designed the lifting methodology and provided the hydraulic equipment (jacks, pumps, hoses, gauges, distribution plates etc.) coordinating the works of the liftings, jackings and bearings replacement.
HiSCS Engineers & Technicians share their experience by training and supervising the executed works in such demanding project (silo under operation with clinker powder covering the area of works). We highlight the importance of routine inspections revealing any defects in structural elements ensuring the Safe for Use and FIt for Purpose (SUFIP) mentality.

24/07/2023

Inspection of Steel Arch Bridge

The Inspection and evaluation of the bearings, stoppers, shear-keys, and viscous dampers of Tsakona arch steel bridge in Korinthos-Tripoli-Kalamata Highway (Southern Greece) has been accomplished by HiSCS Inspectors.
The Tsakona arch bridge is one of the world's longest multi-span arch bridges. It crosses the Tsakona valley bridging a dangerous location with landslides phenomena often occurred the last decades.
It has a total length of 390m, consists of three (3) spans of length 75m - 55m and 260m respectively. The first and second spans form a prestressed reinforced concrete box section, while the third span of 260m long is a steel composite deck suspended by two steel arches trough wire ropes.
The prestressed deck of the bridge rests on the abutment on two (2) free-sliding elastomeric bearings (800x800mm plan area). The shear forces are transmitted through a shear-key device (of 6000KN/±160mm capacity) movable along the longitudinal axis. The deck is monolithically connected on the V shaped pier.
The steel arches are seated on four (4) elastomeric bearings (900x900mm plan area) capable to bear an uplift load of 250KN. In addition, the deck is connected through eight (8) hydraulic viscous dampers with capacity 500KN/±200mm, oriented in the longitudinal and transverse direction of the bridge.
The combination of elastomeric bearings and viscous dampers is one of the best design approaches to secure the seismic protection of a structure.
All inspected elements have been checked about functionality (residual sliding/deformation capacity, rotations/inclination, defects etc.) and a relevant evaluation report has been issued. A special inspection software has been used so as to speed-up the site works.
The inspected elements were manufactured and installed in 2009-2010.
Supporters of a robust inspection and maintenance regime in all structures we are pleased to see that this mentality spreads among the Engineers and Authorities. Inspection and maintenance is considered as a necessity in nowadays.

07/07/2023

Inspection & Evaluation of Dampers in Athens Metro Station

The Inspection and evaluation of one hundred twenty-eight (128) viscous dampers located in the Athens Metro – Line 1, in Marousi station bridge has been accomplished by HiSCS Inspectors.
Viscous dampers are considered anti-seismic hydraulic devices which through hydraulic operation (network of special oil inside internal chambers and orifices in the body of the device) can absorb (consume) kinetic energy, which is produced during the movement of the structure under dynamic actions (earthquake).
The service movements of the structure (temperature effects-contractions/expansions etc.) are taking place with zero reaction of the damper (very low velocity of damper’s piston movement).
The constitutive law of hydraulic damper is exponential, following the formula:

FD = C · Vα (MN)
Where:
C = unit constant [MN x (s/m)α],
V= the velocity of the superstructure (m/s) and
α = an appropriate exponent usually between 0.10 and 0.50.

The exponent α, if it is not specifically defined in the design stage, can be chosen by the manufacturer considering the following criteria:

- the device will not develop resistance to very slow movements of the superstructure (e.g. thermal contractions etc.)
- the device will be activated very quickly in dynamic movements.

The composition of the viscous liquid (oil) and the design details of the device are the know-how of the manufacturer.

The dampers were manufactured in 2004 having the following characteristics:

- Maximum design axial load: 75 KN
- Maximum piston movement speed: 400mm/sec
- Maximum piston extension/compression capability: ±55mm
- Exponent α ~ 0.15 KN/[m/sec] with damping constant C = 30.53
- Nominal axial length (neutral position) from pin to pin: 570mm

The Marousi Metro station is a concrete bridge constructed in 1955-1957 consists of 16 spans with monolithic pier-frames. The bridge serves the metro line needs as a train platform station for the passengers.
Following a regime of structurally upgrading of this old bridge, new concrete columns have been erected along its length connecting the superstructure with steel beams through the dampers, thus implementing the concept of isolating the bridge deck from ground accelerations during earthquake.

The inspection works have been accomplished by a team of 2 inspectors and 2 technicians avoiding any disturbance to the passengers and operation of the station/urban area. A movable working platform has been used to reach the dampers and perform all needed measurements and inspections.

All dampers have been checked and measurements about their function (residual movement capacity, leakage phenomena, rotation, piston condition etc.) have been recorded.
A special inspection software has been used so as to speed-up the site works to a minimum possible (5 days in total, average 25-26 dampers/day).

Hiscs - LMK PT System