Emergency and restoration works on the overpass in the Delyatyn village, Ivano-Frankivsk region
Students Name: Matsopa Ihor Romanovych
Qualification Level: magister
Speciality: Bridges and Transport Tunnels
Institute: Institute of Civil Engineering and Building Systems
Mode of Study: full
Academic Year: 2020-2021 н.р.
Language of Defence: ukrainian
Abstract: Matsopa I.R Emergency and restoration works on the overpass in the Delyatyn village, Ivano-Frankivsk region. Master’s thesis - Lviv Polytechnic National University, Lviv, 2020. Project leader - prof., d.o.e. Kvasha Victor Grigorovich. One of the common types of existing bridges and overpasses, which began to be built en masse in the 50-60s of the last century, are bridges of small and medium girders with prefabricated beam cross-ribbed (diaphragm) girder structures according to the Soyuzdorproekt PI developed in 1956. TP issue. 56 and its later modifications. Currently, the vast majority of bridges with girder structures of this type do not meet the operational consumer properties and standard requirements of the current DBN B 2.3-14 and additions to them DBN B.1.2-15: 2009, DBN B.2.3 22: 2009 for the design of new bridges in first of all on loading capacity, throughput (size of a bridge cloth) and safety and comfort of movement of vehicles and pedestrians. In addition, due to the numerous defects and damage obtained during the period of long-term operation in conditions of unsatisfactory or no care at all, the bearing capacity, reliability and durability of the main load-bearing structures and their unsatisfactory condition in general are further reduced. The girder structure of this bridge is four split girders, each of which is composed of seven diaphragm beams. The girder structures of all girders are made of monolithic reinforced concrete with preservation of geometric dimensions and reinforcement according to the prefabricated version of TP issue 56. During the inspection, particularly dangerous defects of the intermediate main beams were found in the run №2, namely the complete rupture of all six rods (6O32) of the longitudinal reinforcement package in both frames in the middle of the run of three adjacent beams of fatigue, which is clear evidence of complete loss of these beams. bearing capacity and emergency condition of the girder structure. It should be noted that the destruction of bridge beams of this type with reinforcement by multi-row reinforcement due to physical rupture of the package of reinforcement bars without signs of reinforcement fluidity was not observed and is not 8 described in the technical literature. Only one case of fatigue force crack formation was detected in the three lower rods of the reinforcement package with six O32 mm rods/ Study object - is the overpass in the village of Delyatyn, Ivano-Frankivsk region, namely the run №2. Scope of research - is the complete rupture of all six rods (6O32) of the package of longitudinal reinforcement in both frames in the middle of the run of three adjacent beams of fatigue. Goal of research - is to develop technological recommendations for welding of reinforcing bars ? 32 mm. Briefly put research results - on the basis of the conducted researches the technological recommendations of welding of reinforcing rods ? 32 mm by a bath way are developed. The parameters of the mode, the features of the technique, the structural elements of the welded joint are determined. Experimental studies of strength characteristics and structural-phase composition of welded elements of reinforcement were carried out. It is shown that the presence of thermal influence has a negative effect on the properties of the thermal zone. The destruction of the samples occurred on the main metal, mainly in the area of overheating. Technological recommendations for preparation for welding and execution of welded joints of the package of bridge span reinforcement have been developed. The constructive scheme is offered - the scheme of joining of a package from six fittings with distribution of welding zones. It provides the necessary strength characteristics of the welded section of the run and the distribution of loads on the welded joints. Keywords: overpass, bridge beams, emergency condition, monolithic reinforced concrete, beam diaphragms, durability, bearing capacity, longitudinal working armature, bathroom method, load distribution. List of used literature sources: 1. Matarov I.A. Precast concrete bridges with multi-row welded reinforcement. / Matarov I.A., Smirnova L.S., Shilina A.L. // -M.: Avtotransizdat, 1959 .-- 186s. 9 2. DBN V.2.3-6: 2009. Bridges that trumpet. Debauchery that viprobuvannya. – K .: Ministry of Regional Development of Ukraine, 2009. - 31 p. 3. СН 393-69 Instructions for welding joints of reinforcement and embedded parts of reinforced concrete structures. - M .: Publishing house of literature on construction, 1970. - 241 p. 4. Paton B.E. Technology of electric fusion welding of metals and alloys. - Moscow: Mechanical Engineering, 1974.768 p. 5. Kvasha V.G. Pre-service to the package of zvarnoy bagator-poisonous reinforcement of concrete beams for TP vip. 56 and 56d with cyclic navantages / V.G. Kvasha, I.V. Melnik, V.A. Osadchuk, Yu.O. Shalimov, V.I. Biloborodchenko, M.D. Klimpush // Zb. Automobile roads and road construction. –K.: NTU, 2002. –Vip. 64. – S. 89-91. 6. Kvasha V.G. Analysis of the operational mill, the reliability and reliability of the minds of the vitrification of the bridge beams of the dry concrete road bridges / V.G. Kvasha, I.V. Melnik, M.D. Klimpush // Zb. Budivelny constructions. –K .: NDIBK, 1999. –vip. 50. – pp. 482-488. 7. Kvasha V.G. Renovation of built-in reinforcement during the reconstruction of concrete bridges / V.G. Kvasha, I.V. Melnik, V.A. Osadchuk, Yu.O. Shalimov, V.K. Malinovskiy, V.I. Bіloborodchenko // Zb. Budivelny constructions. –K .: NDIBK, 2003. –vip. 59, book 2. – pp. 172-177.