Serbo-Croat term (edited): propusna moć pruge

"railway line throughput" or "railway track throughput", eventually "throughput capacity"

"Intermediate block signalling (IBS). A cost effective method to increase throughput of railways"
http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel4/5616/1...

"Throughput. A railway line can cope with a large train every five or ten minutes."
http://faculty.washington.edu/jbs/itrans/bladerunner1.htm

"To maximize track throughput (trains per day over that section of track), blocks would be sized to match the shortest safe breaking distance of the trains that would use that track."
http://www.freepatentsonline.com/6102340.html

"The Offline Railroad Operations Planner provides recommendations that can increase the capacity and throughput of a railroad line, e.g., it can identify a bottleneck in a railway line and suggest solutions to increase throughput at the trouble spot."
http://statusreports.atp.nist.gov/reports/94-01-0063.htm

"A railway system is made up of vehicles transporting people and goods between facilities (stations) over corridor assets. Vehicle faults identified during inspection can be removed with minor impact on a railway’s throughput. (...) A disruption at just one point in the rail corridor – the railway pinch point – can send a ripple through the entire system. In areas of moderate traffic, a single problem in a two-track corridor can cut throughput by 50 percent or more."
http://www.euinfrastructure.com/pastissue/article.asp?art=27...

"The line capacity of a railway line between two junctions would be determined by the block having highest occupancy time or lowest line capacity. Besides, a railway junction and its associated yard contribute significantly to the throughput bottleneck of the railway network."
http://www.tenet.res.in/Papers/inrail.html

"THE European Train Control System (ETCS) Level 2 allows operators to dispense with lineside signals because train drivers receive their movement authorities by in-cab signalling. Maintenance costs are thus reduced considerably while at the same time safety, reliability and line throughput are enhanced."
http://www.allbusiness.com/electronics/computer-electronics-...

"Upgrading rail infrastructure for greater throughput"
http://esa.un.org/techcoop/flagship.asp?Code=IND94028

"DETERMINING THROUGHPUT CAPACITY OF RAILWAY LINES BY MEANS OF QUEUING THEORY - (...) - UTVRĐIVANJE PROPUSNE SPOSOBNOSTI ŽELJEZNIČKIH PRUGA KORIŠTENJEM TEORIJE MASOVNOG POSLUŽIVANJA"
http://www.fpz.hr/traffic/Casopisi/Promet_02/sazetak24.htm