Load Experiment Conducted When the Bosphorus Bridge Was First Opened

At the moment 15 July Martyrs Bridge The first bridge of the Bosphorus, formerly known as the Bosphorus Bridge, passes thousands of cars from one continent to another every day. The bridge, which was first opened in 1973, had passed an extremely strange test while still under construction, the ethics of which are debated even today.

Today, 15 days before the July 15 Martyrs Bridge was opened to traffic on October 30, 1973. We will describe static loading experiments. The experiments, which tested the weights of the bridge, which was called the Bosphorus at that time, were carried out without taking any serious precautions. Let’s talk about the interesting experiment that this legendary bridge, which has 50 stairs, went through at the beginning of its life.

How did the static loading tests of the 15 July Martyrs (Bosphorus) Bridge take place?

As it was known at that time, it was designed to carry the load of countless vehicles every day. Bosphorus Bridge, It was subjected to static loading tests at the request of the British consulting firm Freeman Fox. Highways decided to apply an extremely interesting method for these experiments. On October 15, 1973, about waiting in line on the Kabataş car ferry. To the driver of 140 trucks “The bridge has been opened, you will pass through it now.” they actually directed the trucks to the unopened bridge.

140 trucks and their drivers who were unaware that they were involved in an experiment, It was filled to make 2.5 lanes on the bridge. After the experiment on the Beylerbeyi side, which lasted about 1 hour, the trucks were unloaded and placed on the Ortaköy side in the same order. After the experiments, which lasted for a total of 1.5 hours, no other trucks were passed over the bridge until the opening.

What was the purpose of the experiment?

By placing weights on both sides of the bridge, the teams measured the maximum strains and maximum steel stresses with strain gauges placed in various parts of the bridge. As a result of the measurements made, the first part of the bridge where the maximum collapse is 123 cm determined. In the second stage of the experiment, the maximum collapse was determined as 124 cm. In the first stage, which caused a 123 cm collapse in these measurements, the bridge was loaded with a load of 1679 tons. Accordingly, the bridge It has been calculated that there will be a load of 2650 tons that it can safely carry from tower to tower. It was calculated that the bridge would reach a serious collapse value of 190 cm under this load.

In order to reach 2650 tons, which is determined as the safe traffic load for the Bosphorus Bridge, it will be sufficient for trucks with an average weight of 20 tons and an average length of 10 meters to fill 1.5 lanes by placing them on the bumper. 6 lanes in total. If only 3 lanes of the Bosphorus Bridge were filled in this way, it would make a load of 6440 tons. and that is enough weight for the bridge to collapse.

How does the July 15 Martyrs Bridge cope with this weight today?

As you can see, the Bosphorus with its old name, the 15 July Martyrs Bridge with its new name, is an extremely old bridge. The weights it can carry are also in the middle. Considering the increasing traffic density in Istanbul, various measures need to be taken in this regard. Today, apart from the municipality and public buses from the bridge, large-tonnage vehicles such as trucks and trucks vehicles are prohibited.

So how did you find the experiment on the 15 July Martyrs Bridge? approaching the age of 50 Although there are various controls, you can share your thoughts about this bridge with us in the comments section.