Transient infiltration tests in pyroclastic soils with double porosity  

作　　者：Ciro SEPE Domenico CALCATERRA Emilia DAMIANO Diego DI MARTIRE Roberto GRECO Lucia PAPPALARDO Massimo RAMONDINI Enza VITALE Giacomo RUSSO 

机构地区：[1]Department of Civil and Mechanical Engineering,University of Cassino and Southern Lazio,Cassino 03043,Italy [2]Department of Earth Science,Environment and Resources,University of Napoli Federico II,Napoli 80126,Italy [3]Dipartimento di Ingegneria,Universitàdegli Studi della Campania“L.Vanvitelli”,Aversa 81031,Italy [4]Istituto Nazionale di Geofisica e Vulcanologia,Sezione di Napoli-Osservatorio Vesuviano,Napoli 80124,Italy [5]Department of Civil and Environmental Engineering,University of Napoli Federico II,Napoli 80125,Italy

出　　处：《Journal of Mountain Science》2023年第11期3327-3342,共16页山地科学学报（英文）

摘　　要：Fallout volcanic deposits of SommaVesuvius(Campania,southern Italy),characterized by the presence of layers with contrasting textural and hydraulic properties,are frequently affected by shallow landslides during rainwater infiltration.The soils of the stratigraphic sequence present intraparticle pores,originated by the gases escaped during magma decompression in the volcanic conduit,thus are characterized by double porosity(i.e.,intraparticle and interparticle pores),which is expected to affect their hydraulic behaviour,and to play a key role in rainwater infiltration through layered deposits.To understand the effect of double porosity on the hydraulic behaviour of the involved soils,controlled experiments have been carried out in an infiltration column.The experimental apparatus is provided with newly designed non-invasive Time Domain Reflectometry(TDR)probes,not buried in the investigated soil layers so as to minimize disturbance to the flow,allowing water content measurement during vertical flow processes.Specifically,transient flow experiments are carried out through reconstituted specimens of black scoriae and grey pumices,both loose pyroclastic granular soils from fallout deposits of Somma-Vesuvius,featuring double porosity with different pore size distributions,that were estimated by X-ray tomography and Mercury Intrusion Porosimetry.The experimental results highlight the effects of the double porosity and clearly indicate the different behaviour of the two soils during wetting and drying processes,mainly related to the different dimensions of intraparticle pores.

关 键 词：Double porosity soil Non-invasive TDR probes Vesiculated soil particles Pyroclastic soils X-ray tomography Mercury intrusion porosimetry 

分 类 号：P642.2[天文地球—工程地质学]