INNOVATIVE INTEGRATED METHODOLOGY FOR THE USE OF DECONTAMINATED RIVER SEDIMENTS IN ROAD CONSTRUCTION Progress Meeting September 10 th 2015 Prof. Ing. Massimo Losa Dott. Ing. Pietro Leandri Dott. Ing. Patrizia Rocchio

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ B. Implementation actions ACTION B.4: Demonstration of the use of decontaminated sediments in road construction Specific technical goals : - preliminary assessment of the optimum percentage of lime for the stabilization of sediments to be used in the construction of the road section; -construction of a road section for the demonstration of the use of sediment mixtures in the construction of low volume roads. C. Monitoring of the impact of the project actions ACTION C.3: Monitoring and validation of the use of decontaminated sediments for road construction construction ACTIONS Murcia - September 10 th, 2015

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 1 st Step : Treatment of the dredged sediments Main problem: excessive water content (that do not allow dredged sediments to ensure appropriate bearing capacity). It is necessary to reduce the water content at least up to 15-20%. Laboratory procedure: realization of dewatering system for moisture control The sediment samples were tested periodically to check the variation of water content as a consequence of natural drying in order to assess the amount of water that the system naturally loses by evaporation and / or drainage. Murcia - September 10 th, 2015 reproduced in a reduced scale: Environmental temperature and moisture conditions:  no rain and/or direct radiation  almost constant temperature (20°C) Field conditions :  lower drainage  lateral confinement  surface aeration In situ procedure: 30 cm lime layer was laid on a draining material and rehashed mechanically in order to allow the air-drying.

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 1 st Step : Treatment of the dredged sediments Dewatering system for moisture control Murcia - September 10 th, 2015 TOP MIDDLE BOTTOM

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 1 st Step : Treatment of the dredged sediments Dewatering system for moisture control: Results Murcia - September 10 th, 2015 In controlled environmental conditions, the moisture content can be reduced up to 40% after a period of 7-8 weeks

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 1 st Step : Treatment of the dredged sediments Dewatering system for moisture control: Results Murcia - September 10 th, 2015 Remarkable difference between the in situ and laboratory processes:  in situ environmental conditions cannot be controlled  similarly to the laboratory process, after dewatering the sediments showed a water content of about 40 % after 5-6 weeks. the level is still too high to allow the sediments workability in order to reduce the water content and the dewatering process time, the partially dewatered sediments were mixed with lime Lime hydration process decreases the soil moisture content. CaO + H 2 O = Ca (OH) kcal The reaction is exothermic and heat generated from this chemical reaction further dries wet sediments by driving it off as steam.

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 1 st Step : Treatment of the dredged sediments Murcia - September 10 th, 2015 In order to reduce the water content up to the level required for compaction, dredged sediments were mixed in laboratory with different lime percentages and the related water loss was evaluated.

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 1 st Step : Treatment of the dredged sediments Murcia - September 10 th, 2015 Lab stabilization results: %CaO versus water content The optimum water content of about 20%, determined by the Proctor compaction curve was obtained by using a lime percentage greater than 15%.

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 Conclusion : Road construction up to 15%. in order to reduce the water at a value near to Proctor moisture optimum level (19%), the lime percentage required for the stabilization (5.2%) is increased up to 15%. Double effect : stabilization of the sediments and drying Murcia - September 10 th, 2015 Dredged sediments dryed and stabilized with lime

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION B.4 ACTION B.4 Completed with road construction Murcia - September 10 th, 2015

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION C.3 ACTION C.3 1 st Step : Field investigation Murcia - September 10 th, 2015 Each layer was laid only after the situ performance check of the layer to be covered. The following parameters were monitored in situ:  moisture content of dredged sediments stabilized with lime (BS 6576);  field density of dredged sediments stabilized with lime was measured after compaction by the sand-cone apparatus (CNR BU n. 22/72);  elastic Modulus of compacted layers by using the static and dynamic plate load tests (B.U. C.N.R. n. 146/1992, ASTM E2835–11; ASTM E2583–07 (2011) ); this parameter is a good indicator of the bearing capacity of the embankment;  In-situ and laboratory CBR index (ASTM D , UNI EN :2012 );  full characterization of the asphalt mix (volumetric and mechanical characteristics)

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION C.3 ACTION C.3 1 st Step : Field investigation Murcia - September 10 th, 2015 Field density Static load plate test Dynamic load plate test Dynamic Cone Penetrometer (DCP) test - CBR in situ test In situ tests on asphalt binder mixture by using a Mobile Laboratory

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION C.3 ACTION C.3 Settlements monitoring Murcia - September 10 th, 2015 In order to evaluate the behavior of the embankment under working conditions, a magnetic extensometer system for monitoring settlements over time was installed Installation of extensometer system

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ ACTION C.3 ACTION C.3 Settlements monitoring Murcia - September 10 th, 2015 Sounding manhole The monitoring activities will be completed through the measurement of settlements over time in order to evaluate the behavior of the embankment under working conditions (traffic loads)

“Innovative integrated methodology for the use of decontaminated river sediments in plant nursing and road construction” CLEANSED - LIFE 12 ENV/IT/ Murcia - September 10 th, 2015 ACTION C.3 ACTION C.3 Settlements monitoring The monitoring activities will be completed through the measurement of settlements over time in order to evaluate the behavior of the embankment under working conditions (traffic loads)