ISBN-13: 9783843325059 / Rosyjski / Miękka / 2011 / 156 str.
V nastoyashchee vremya v mire 60 % zheleznykh dorog ispolzuyut derevyannye shpaly. Ostalnoy protsent sostavlyayut zhelezobetonnye, i polimernye shpaly. Srok sluzhby sosnovoy shpaly sostavlyaet ne bolee 12 let, srok sluzhby zhelezobetonnykh shpal sostavlyaet okolo 50 let. Nedostatki prisushchi i zhelezobetonnym shpalam: otsutstvuet dempfernoe svoystvo u shpaly, iz-za chego proiskhodit razrushenie kolesnykh par sostavov; uvelichenie sluchaev porazheniya lyudey elektricheskim tokom vsledstvie khoroshey provodimosti toka zhelezobetonom; vynuzhdennye zameny iz-za iznosa amortizatsionnykh prokladok kazhdye 7-8 let, chto privodit k bolshim zatratam pri ekspluatatsii shpal. Na lesosekakh Rossii ezhegodno sgnivaet poryadka 70 mln. m3 drevesiny myagkikh listvennykh porod bereza, osina, olkha. Shpala, izgotovlennaya iz pressovannoy drevesiny po svoim fiziko-mekhanicheskim pokazatelyam ne ustupaet derevyannoy, no srok sluzhby sushchestvenno vyshe, chem derevyannoy. Odnim iz osnovnykh nedostatkov uplotnennoy drevesiny yavlyaetsya nizkaya formoustoychivost pri vozdeystvii vlagi i vody.Dlya povysheniya formoustoychivosti predlagaetsya propitat drevesinu pered pressovaniem sostavom na osnove karbamidoformaldegidnykh soedineniy.