bridges over the river Kei

The article is the outcome of the author's long-standing interest in the number and variety of bridges that were built within a short section of the Great Kei River at Victoria Drift - in close proximity to the village of Komgha - over a 100-year period. The particular bridges under scrutiny - with their dates of construction - are as follows: Temporary Military Bridge, 1877 (no longer extant) Lattice Girder Wagon Bridge, 1879 Timber Railway Bridge, 1905 (only foundations remaining) Relocated Lattice Girder Railway Bridge, 1948 N2 SANRAL Concrete Bridge, 1977.

Military Bridges and Their Usage in Emergency (Natural Disasters) Situations

The role of military bridges in military-civilian operations is very important. The introductory part briefly discusses the classification of military bridges and their brief history of development, highlighting the importance of military bridges during hostilities. The main part discribes the usage of military-engineering subdivisions, in particular, military bridges, during civilian military operations, such as their use in the elimination of natural or technogenic disasters. The article discusses examples of the use of military bridges in the last part of the history of Georgia, their importance during the liquidation of the crisis, such as: the use of a military bridge (КМ-02Т) in the construction of IDP settlements in the post-war Georgia, the use of infrastructure damaged by the Nenskra River in the Svaneti region, and the use of spinal bridges over the Terg River in Kazbegi Municipality. The use of military bridges is one of the best examples of military civilian operations.

Research on Lightweight Technology Application in River-Crossing and Military Bridge Equipment

Lightweight technology application in river-crossing and military bridge equipment has important significance to promote rapid development. Lightweight can efficiently reduce the weight, promote structure optimization and improve performance of the river-crossing and military bridge equipment. After basic principles and main technologies of the lightweight application in the river-crossing and military bridge equipment components are summarized, strength design technologies for the lightweight of the equipment components are discussed, and simple shape components strength design criteria under tension/ compression, bending, shearing and torsion are analyzed, which is extended to general lightweight components strength design criteria. On the basis of the lightweight design principles and strength design criteria, appropriate design methods and optimization strategies are selected, suitable lightweight high-strength material is chosen according to research and development demands, and the lightweight purpose for the river-crossing and military bridge equipment is realized.

The application of composites (FRP) in military bridges

The needs of expeditionary forces involve the use of light-weight, short-span bridges so that their transport by air would be possible. A project which is currently developed in USA aims at the elaboration of a Composite Army Bridge (CAB) assault bridge and a Modular Composite Bridge – MCB logistic bridge. In 2004 CAB successfully underwent fatigue tests. A 14 m-long, all-composite treadway bridge span was loaded by using an MLC 100 vehicle and it withstood 20 000 load cycles. The MCB will be constructed by7 m of box modules and a 6.5 m access ramp. A 26 m-long and 4 m-wide bridge span is to provide the traffic ability of MLC 65. Furthermore, works on a 10 m-long, MLC 30 composite bridge are also developed in Canada too. The paper also presents the American concept of employing a deployable bridge system by utilising a composite structure. In order to formwork and reinforce the plate, fibre reinforced polyester composites (FRP) were used. The girder construction is made of aluminium pipes forming diamond truss with curved bottom chord. After they are integrated in the structure, the top chord nodes are connected through deck plate cast in-situ. The tests indicated that there exists the possibility of using polymer composites in military bridge construction and mobile structures of composite bridges.

REALIZATION OF LOGISTICAL VENTURE IN CONDITIONS OF RISKS

The material presents an analysis of a potential risk assessment of operating military bridge facilities. Three types of steel military bridges were analysed: assembled bridges, vehicle-launched bridges and low-level bridges. The material presents an original method of a fatigue risk factor analysis. Furthermore, the author presents potential applications of the AHP method to determine weights for risk factors under analysis. It is assumed that at the further stage of research a thorough identification and quantification of other risk factors will be conducted.