The Jamarat Bridge, in Mina, is a pedestrian bridge which is most famously used by millions of pilgrims whilst they perform the Stoning of the Devil ritual of the Hajj. 

The Jamarat bridge is constructed around three pillars, which mark the place where, according to Islamic tradition, Prophet Ibrahim was confronted with Satan and so threw stone at him to resist his temptations. Following in the footsteps of Prophet Ibrahim, pilgrims are required to also throw stones at these three place to remind themselves to the temptation of Satan in everyday life. 

The logistics of managing millions of people at this location has always been a challenge for the Hajj authorities. In 2006 in one of the worth tragedies at the Jamarat, 364 people were Killed in a stampeded at the entrance of the Bridge. To address the congestion at this location, the Saudi government launched at $1.2 billion project to revamp the bridge. 

The completion of the fifth and final phase of the project was announced in November 2009, ready in time for the next Hajj season. The 950m-long bridge is 80m wide and has been designed to carry as many as 12 storeys to accommodate up to five million pilgrims i the future if need arises. 

A monitoring system installed by Strainstall Middle East measures the deflection of the structure that occurs due to dead loads, superimposed dead loads and the live load caused by the moving Pilgrims during the Hajj period. The system also measurement the vibrations resulting from the movement of the pilgrims. These measurement are taken over a period of time, so the long term effects can be determined.  

A data acquisition system allows all the monitoring data to be stored in the hard drive of the connected PC, which can be retrieved as and when required. The system also includes the software package Strainsoft, which has been developed by James Fisher Strainstall for presenting the data acquired from the data acquisition system in a graphical and easy to interpret format.