Besides its Controversial History, Izvor Tunnel, Figures and Data

At the execution of the railway works in our country, of any type would be that, there have been utilized, as much as possible, the most advanced methods and machines, aiming the provision of the lasting works, of a special demeanor, and especially of the possibility to be used for the traffic speeds as increased as possible and to the maximal axle load. From the researches performed to these works and means of transport used there can be easily met the technical degree of the epoch in which they have been executed.

..1968
If in the previous issue of the magazine we have drawn your attention with the story of Izvor tunnel as the people of the place remember it, in the following lines, having the support of a real railway employee - Mr. Serban Lancranjan -, we have entered in the possession of certain documents, part of the written history of the Romanian Railways, including concrete technical data regarding the building of the respective tunnel.
In order to decongest the railway knots Bucharest and Ploiesti and for shortening the route from western and northern of the country through Predeal, in year 1913, the management of CFR has established the execution of a direct connection between the stations Titu and Sinaia through Targoviste, Pietrosita and Moroieni.
On this purpose, there has been also concluded a contract with the company belonging to the engineer Julius Berger for the construction of an integral railway line, which was about to link the stations Sinaia and Pietrosita. The route being located in the southern area of Bucegi Mountains, there was necessary the penetration of the mountain slope through a tunnel that was going to have a 5,918 m. If it has been finalized, this one would have been the longest tunnel in the country even nowadays.
Fact that only a few are aware of is that this line was part of a great program of investments initiated by the general director of CFR from that time, Al. Cottescu, for the achievement of which there have been made, in 1914, a internal loan of 480 million ROL in gold. The lines stipulated to be executed (some of them, studied still since 1892 - 1893) were: Bucharest - Rosiori - Craiova, Faurei - Tecuci, Pascani - Tg. Neamt, Pantelimon - Urziceni - Faurei, Moroeni - Sinaia, Buhaiesti - Roman, Zimnicea Port. Still then there has been discussed about the normalization of the Crasna - Husi railway line and about the continuation of the section from Medgidia to Tulcea. Unfortunately, the starting of the First World War has allowed ony the beginning of a few works.
Resuming, we remind the fact that the work has been contracted in year 1913, having as execution deadline 28 months. This way its achievement, conditioned by a working program in three shifts, of eight hours, has been started off on January 1914 and has been continued in a sustained rhythm up to August of the same year. In the meantime there have been achieved 400 m of complete tunnel, including the portals, the clothing and the radier, being executed the basic top galleries of a 800 lm length. This was the situation on August 1914, when, due to the starting of the war, the works have been ceased.

Technical data
The tunnel has been built in alignment - less the endings, being achieved in curves of a 300 m beam. Being a top tunnel, it had slopes toward the endings. The top spot (of breaking of the two slopes) was stipulated even at the middle of the tunnel. The northern branch (to Sinaia) was going to have a 2,960 m length and a declivity of 1 …. . and the southern branch (to Carpinis) - 2,958 m and the declivity of 3.30 ….
The entrance from Sinaina was situated on the right side of the valley of Prahova river, in Izvor village, at 4 km downwards from Sinania Railway Station. In order to reach the tunnel the way had to penetrate a valley of 20 meters depth and 150 m width, so that for the access to the working spot (the tunnel opening), over the respective valley has been built a wooden bridge, which in time has started to rotten. The exit from the tunnel was the Ialomicioarei Valley, at Caprinis.
The nature of the rocks that had to be dislocated, the water springs and the gas emanations occurred during the execution of the works have produced several difficulties, slowing down its advancement. Therefore, on around 450 m to north (Sinaia) and 750 m to south (Carpinis) there were a few geological formatiuni of sedimentary rocks, in rest being recorded important variations in the stratification, starting with the hard rocks, compact, and up to the weak banks, of lime stone and even a mellow bedrock.
On the northern part the water infiltration have been very powerful fact that has led to great difficulties while advancing and imposed the achievement of certain strong supports, which were spread sometimes up to the advancement point. On the northern side, the problems have been quite big due to the metan gas emanations that have occurred through the cracks and hindered the continuation of the works. Due to the fact that the structure of the rocks was unstable and partially degraded, there have been adopted for the excavation an Austrian working method - the advancement through the top gallery, the support being provided with strong, special beams.
The work has been attacked from both sides of the mountain, using string power station and air compressors, concrete manufacturing machines and other machines, summing up to 1,600 HP.
The section of the tunnel (the surface for the free profile) was of 30 m2 the middle height having 6.50 m, and the width of 5.30 m. the basic surface has been of 10 m2 and the top gallery of 6.5 m2. The overall surface of the excavation has been of 56 m2 .
The tunnel has the clothing by moloane of stone, with a 1- 1.2 m thickness on its entire length, excepting the entrance from Carpinis, where there were great pressures and that's why the clothing has been achieved with non-symmetrical sections, having downstream the thickness in the right foot of 2.70 m and the foundation of 4 m, and upstream the thickness of the right foot being of 1.10 m and the foundation of 1.25 m. Concomitantly, the tunnel was stipulated with a walled general radier (a turned over vault) of a 0,75 m thickness, the channel for waters drainage being centrally built.
As we have already mentioned the work has been interrupted once with the inception of the First World War; the site has been abandoned, and the works that have been already executed have not been taken over by any CFR unit.
After the termination of the war the Austrian company has been called again in the country, yet for the execution of other works, considered at that times, more urgent: the linking railway section between Harman and Nehoiasi, through Teliu and Intorsura Buzaului - where there has been executed the Teliu tunnel for a double line, of 4,376 m length (which is today the longest tunnel on CFR network), as well the viaduct over the Teliu Valley, of 142 m length, with seven concrete vaults.
The site from Izvor Tunnel has been still maintained by the constructing company, considering that the work will be resumed after the finalization of the one in Teliu. From unknown reasons yet, according to our documents, the works have never been continued and, in year 1932, the site has been annulled.
Over more than 30 years, in 1968, in order to ascertain the state of the work, there has been searched the tunnel ending from Sinaia. The wooden bridge making available the access to the tunnel has been degraded, and the access to the opening of the tunnel has become more difficult, being possible only on certain paths that are considered almost inaccessible. The opening of the tunnel has been more than half covered with detritus fallen from the mountain. The masonry from the clothing has been maintained very well, up to that year, and it was still dry, being possible to notice only a few small spots of eflorescente. On a 170 m length, the tunnel section was empty being possible the operation, fact that allows certain usage.
At 170 m since the end from the northern side there was a ventilation chimney. In this spot, from the uruis fallen on the chimney has been formed a bigger chimney, clogging almost completely the section and hindering the advancement. Besides this point, the tunnel continues on 64 m more, yet the access being quite difficult, due to the material that has fallen. The basic and the top galleries are fallen apart because the supporting timber has rotten. With respect to the state of the works at the end from the southern side an analysis has not been succeeded, in year 1968.

Unfortunately, these are the only information, which we have found out in an article published in the Railways Magazine in year 1969. We have not discovered yet a document certifying the exact number of the Romanian employees that have worked on this project, and about what happened with them once with the stopping of the works…nothing!

Magdalena Fedeles