%20--%3e%3csvg%20version='1.1'%20id='Layer_1'%20xmlns='http://www.w3.org/2000/svg'%20xmlns:xlink='http://www.w3.org/1999/xlink'%20x='0px'%20y='0px'%20viewBox='0%200%20100.6%2073.7'%20style='enable-background:new%200%200%20100.6%2073.7;'%20xml:space='preserve'%3e%3cstyle%20type='text/css'%3e%20.st0{fill:%23AF001E;}%20.st1{fill:%23FFFFFF;}%20%3c/style%3e%3cg%3e%3crect%20class='st0'%20width='100.6'%20height='73.7'/%3e%3cpath%20class='st1'%20d='M25.2,36.3l-0.5,2.3c-0.2,0.7-0.2,1-0.2,1.2c0,0.5,0.2,1,0.5,1.6L31.5,53c0.5,0.9,1,1.3,2.3,1.3h5.9%20c0.8,0,1.7-0.5,0.8-1.8l-7.9-13.1c2.7-1.7,5.6-4.1,5.6-9.3c0-6.8-3.8-10.6-12.2-10.6H13.9c-1.1,0-1.4,0.4-1.4,1.5v32%20c0,1.1,0.3,1.5,1.4,1.5h5c1.1,0,1.4-0.4,1.4-1.5V26h5.2c3.3,0,4.8,1.2,4.8,4.2c0,2.8-1.2,3.6-2.5,4.2C26.3,35,25.7,34.3,25.2,36.3z%20'/%3e%3cpath%20class='st1'%20d='M45.9,48.8L45.3,53c-0.1,0.8,0.3,1.1,1,1.2c1.6,0.2,5.5,0.5,9.4,0.5c8.6,0,14.9-2.8,14.9-10.9%20c0-4.7-2.1-8.3-9.2-10.1l-4-1c-2.7-0.7-4-1.6-4-3.6c0-2.8,2.6-3.4,5.1-3.4c3.4,0,6.8,0.3,8.1,0.4c1.4,0.1,1.8-0.1,2-1.2l0.7-4.1%20c0.1-0.8-0.3-1.1-1-1.2c-1.6-0.2-5-0.5-9.4-0.5c-9,0-13.3,3.9-13.3,10.1c0,5.6,3,8.9,8.3,10.3l4,1c3.3,0.9,4.7,1.8,4.7,3.9%20c0,3-2.1,3.6-7.1,3.6c-2.3,0-6.2-0.3-7.6-0.4C46.5,47.4,46.1,47.6,45.9,48.8z'/%3e%3cpath%20class='st1'%20d='M79.4,52.9c0,1.1,0.3,1.5,1.4,1.5h5c1.1,0,1.4-0.4,1.4-1.5v-32c0-1.1-0.3-1.5-1.4-1.5h-5%20c-1.1,0-1.4,0.4-1.4,1.5V52.9z'/%3e%3c/g%3e%3c/svg%3e)
La diga dell’Isola di San Bernardino necessita di un intervento per allentare le tensioni nel cemento, che si è gonfiato leggermente. È quanto emerso dalle ultime misurazioni effettuate dall’Azienda elettrica comunale di Mesocco, controllata della Axpo Holding.
Il rigonfiamento del calcestruzzo è un fenomeno noto in tutto il mondo e deriva da una reazione chimica, nel caso della diga Isola scatenata dalle sostanze della regione che contengono solfati utilizzate proprio nella produzione del cemento.
Dalla sua costruzione (1957-1963), il muro si è deformato sotto la pressione interna di circa 60 millimetri "in modo continuo e irreversibile verso il lato dell'acqua". Durante il prossimo inverno Axpo prevede quindi di rimuovere uno strato di circa 30 millimetri, allentando la tensione e permettendo l’espansione del calcestruzzo.
La procedura si basa su una tecnica collaudata e il completamento dei lavori, che costeranno circa 2,5 milioni di franchi, è previsto per la prossima primavera.
La diga di San Bernardino si "gonifa"
Il Quotidiano 22.08.2019, 21:30
Entra nel canale WhatsApp RSI Info
Iscriviti per non perdere le notizie e i nostri contributi più rilevanti
https://whatsapp.com/channel/0029Vat6p4zL2ATyO8IRFJ2C
%20--%3e%3csvg%20version='1.1'%20id='Layer_1'%20xmlns='http://www.w3.org/2000/svg'%20xmlns:xlink='http://www.w3.org/1999/xlink'%20x='0px'%20y='0px'%20viewBox='0%200%20138.2%2048'%20style='enable-background:new%200%200%20138.2%2048;'%20xml:space='preserve'%3e%3cstyle%20type='text/css'%3e%20.st0{fill-rule:evenodd;clip-rule:evenodd;fill:%23AF001E;}%20.st1{fill-rule:evenodd;clip-rule:evenodd;fill:%23FFFFFF;}%20%3c/style%3e%3cpath%20class='st0'%20d='M0,48h138V0H0V48z'/%3e%3cpath%20class='st1'%20d='M9.3,31.7l-0.4,2.7C8.8,35,9,35.2,9.5,35.3c2,0.2,4,0.3,6.1,0.3c5.6,0,9.7-1.8,9.7-7.1c0-3.1-1.3-5.4-6-6.6%20l-2.6-0.7c-1.8-0.5-2.6-1-2.6-2.3c0-1.9,1.7-2.2,3.3-2.2c2.2,0,4.4,0.2,5.3,0.2c0.9,0.1,1.2,0,1.3-0.8l0.4-2.6c0-0.1,0-0.2,0-0.3%20c0-0.1-0.1-0.2-0.1-0.3s-0.1-0.1-0.2-0.2c-0.1,0-0.2-0.1-0.3-0.1c-2-0.2-4.1-0.3-6.1-0.3C11.8,12.4,9,14.9,9,19c0,3.6,2,5.8,5.4,6.7%20l2.6,0.7c2.1,0.6,3,1.2,3,2.5c0,2-1.3,2.3-4.6,2.3c-1.5,0-4-0.2-4.9-0.3C9.6,30.9,9.4,31,9.3,31.7'/%3e%3cpath%20class='st1'%20d='M36.4,23.6l-0.3,1.5C36,25.4,36,25.6,36,25.9c0,0.4,0.1,0.8,0.4,1.1l4.2,7.6c0.1,0.3,0.3,0.5,0.6,0.7%20c0.3,0.2,0.6,0.2,0.9,0.2h3.8c0.5,0,1.1-0.3,0.5-1.2l-5.1-8.6c1.7-1.1,3.6-2.6,3.6-6.1c0-4.4-2.5-6.9-7.9-6.9h-7.8%20c-0.7,0-0.9,0.2-0.9,1v20.8c0,0.7,0.2,1,0.9,1h3.2c0.7,0,0.9-0.2,0.9-1V16.8h3.3c2.1,0,3.1,0.8,3.1,2.8c0.1,0.6,0,1.2-0.3,1.6%20c-0.3,0.5-0.7,0.9-1.3,1.1C37.1,22.7,36.8,22.3,36.4,23.6z'/%3e%3cpath%20class='st1'%20d='M66.1,34V22.7c0-0.7-0.2-1-0.9-1h-5.8c-0.7,0-0.9,0.2-0.9,1v2.5c0,0.7,0.2,0.9,0.9,0.9h1.7v5%20c-0.6,0.1-1.1,0.1-1.7,0.1c-4.8,0-6-3.1-6-7.4c0-5.4,2-6.8,6.5-6.8c1.3,0,3.1,0.1,4.1,0.2c1,0.1,1.2,0,1.3-0.8l0.4-2.5%20c0.1-0.7,0-1-0.8-1.1c-1.8-0.2-3.6-0.3-5.4-0.2c-8.2,0-11.6,4.3-11.6,11.3s2.7,11.9,11.3,11.9c2,0.1,4,0,6-0.4%20C65.9,35.2,66.2,34.9,66.1,34'/%3e%3cpath%20class='st1'%20d='M74.9,31.7l-0.4,2.7c-0.1,0.5,0.2,0.7,0.6,0.8c2,0.2,4,0.3,6.1,0.3c5.6,0,9.7-1.8,9.7-7.1c0-3.1-1.3-5.4-6-6.6%20l-2.6-0.7c-1.8-0.5-2.6-1-2.6-2.3c0-1.9,1.7-2.2,3.3-2.2c2.2,0,4.4,0.2,5.3,0.2c0.9,0.1,1.2,0,1.3-0.8l0.4-2.6c0-0.1,0-0.2,0-0.3%20c0-0.1-0.1-0.2-0.1-0.3s-0.1-0.1-0.2-0.2c-0.1,0-0.2-0.1-0.3-0.1c-2-0.2-4.1-0.3-6.1-0.3c-5.8,0-8.6,2.6-8.6,6.6%20c0,3.6,2,5.8,5.4,6.7l2.6,0.7c2.1,0.6,3,1.2,3,2.6c0,2-1.3,2.3-4.6,2.3c-1.5,0-4-0.2-4.9-0.3C75.3,30.8,75,30.9,74.9,31.7'/%3e%3cpath%20class='st1'%20d='M93.1,31.7l-0.4,2.7c-0.1,0.5,0.2,0.7,0.6,0.8c2,0.2,4,0.3,6.1,0.3c5.6,0,9.7-1.8,9.7-7.1c0-3.1-1.3-5.4-6-6.6%20l-2.6-0.7c-1.8-0.5-2.6-1-2.6-2.3c0-1.9,1.7-2.2,3.3-2.2c2.2,0,4.4,0.2,5.3,0.2c0.9,0.1,1.2,0,1.3-0.8l0.4-2.6c0-0.1,0-0.2,0-0.3%20c0-0.1-0.1-0.2-0.1-0.3c-0.1-0.1-0.1-0.1-0.2-0.2c-0.1,0-0.2-0.1-0.3-0.1c-2-0.2-4.1-0.3-6.1-0.3c-5.8,0-8.6,2.6-8.6,6.6%20c0,3.6,2,5.8,5.4,6.7l2.6,0.7c2.1,0.6,3,1.2,3,2.6c0,2-1.3,2.3-4.6,2.3c-1.5,0-4-0.2-4.9-0.3S93.1,30.9,93.1,31.7'/%3e%3cpath%20class='st1'%20d='M120.2,23.6l-0.3,1.5c-0.1,0.3-0.1,0.5-0.1,0.8c0,0.4,0.1,0.8,0.3,1.1l4.2,7.6c0.1,0.3,0.3,0.5,0.6,0.7%20c0.3,0.2,0.6,0.2,0.9,0.2h3.8c0.5,0,1.1-0.3,0.5-1.2l-5.1-8.6c1.7-1.1,3.7-2.7,3.7-6.1c0-4.4-2.5-6.9-7.9-6.9H113%20c-0.7,0-0.9,0.2-0.9,1v20.8c0,0.7,0.2,1,0.9,1h3.2c0.7,0,0.9-0.2,0.9-1V16.8h3.3c2.1,0,3.1,0.8,3.1,2.8c0.1,0.6,0,1.2-0.3,1.6%20c-0.3,0.5-0.7,0.9-1.3,1.1C120.9,22.7,120.6,22.3,120.2,23.6'/%3e%3c/svg%3e)