Comparisons of different concrete mixes for trough lids for S & T cable ducts (TM-CES-36)

In 1981 a request was received from B.R. Southern Ragion for Darby R & DD to design a 'more substantial' concrete troughing lid for the Signalling & Communications cable ducts which run alongside the track. At present the lids are produced using a standard mix reinforced with a steel mesh,...