Evaluation of the risk associated with karstic processes in Miocene gypsum in south-eastern Madrid (Spain)

Relief formations characteristic of karstification processes affecting the Miocene gypsum formations existing in south-eastern Madrid have been discovered in that area of the city. These relief formations can pose significant risks to future urban development plans.The purpose of this article is to present an integrated model created from a geomorphological analysis of south-eastern Madrid through aerial photographs, geophysical inspections (microgravimetry) and geotechnical studies (in situ drilling and testing), in order to identify and measure the morphologies associated with karstic processes whose locations, dimensions and geotechnical characteristics are prone to causing damages that could pose a potential risk. The risk analysis is based on a study of the risk factors, focusing on vulnerability and the measurement of structural mitigation measures capable of preventing the damages that could be caused by the interaction between structural foundations and the morphological consequences of karstic processes on the soil.Ocena tveganj povezanih z zakrasevanjem miocenske sadre v jugovzhodnem Madridu (Španija)V jugovzhodnem Madridu je veliko reliefnih oblik, ki kažejo na zakrasevanje miocenske sadre. To predstavlja tveganje, ki ga moramo upoštevati pri urbanističnem načrtovanju. V članku predstavljamo celovit pristop, ki temelji na geomorfoloških analizah aeroposnetkov, mikrogravimetričnih in geotehničnih raziskavah, s katerim smo zaznali in izmerili morfološke značilnosti, ki so povezane z aktivnim zakrasevanjem sadre. Analiza tveganj temelji na študiji dejavnikov tveganja in se osredotoča na ranljivost in oceno uspešnosti strukturnih ukrepov za blažitev vpliva zakrasevanja v prsti na strukturne temelje

Empleo de ecuaciones constitutivas mediante Hardenig Soil Model para la caracterización de las Margas Azules del Guadalquivir a partir de ensayos presiométricos

Los ensayos presiométricos ejecutados en sondeos han demostrado ser una herramienta eficaz en los estudios geotécnicos destinados a obras de infraestructura civil. Un aprovechamiento intenso del mismo, consiste en la comparación de sus resultados con los obtenidos de un modelo matemático gobernado por una ecuación constitutiva representativa del terreno. En ese artículo se presenta un modelo numérico, de anillos concéntricos, regidos por la ecuación constitutiva del Hardening Soil Model que pretende ser un marco de referencia para la interpretación del ensayo. El modelo analiza variables como son: los modos de respuesta, el estado inicial, el régimen de drenaje, y las ecuaciones constitutivas, pudiendo ser aplicado a cualquier formación geológica de la que se disponga de un número representativo de ensayos

Chemical Injections Realized with Null Pressure for Underpinning the Foundation of an 18th Century Building Located in the Historical City of Cuenca (Spain)

Chemical injection of expansive polyurethane resin in the ground is a well-known technology that is also used for underpinning shallow foundations. It is noteworthy that it has been recently used with success on buildings of great historic value that are part of the country’s architectural heritage. This article describes the work undertaken on a historic building located in the city of Cuenca (Spain), for improving ground condition through injecting below foundation, in order to stop the differential settlements detected in the structure. This technology has proven to be, at least, as effective as the more conventional methods used in the past as supporting the foundation by concrete shafts or micropiles

Underpinning of shallow foundations by expansive polyurethane resin injections. Case study: Cardinal Diego de Espinosa Palace in Segovia (Spain) = Recalce de cimentaciones superficiales mediante la inyección de resina de poliuretano expandido. Caso de estudio: Palacio del Cardenal Diego Espinosa, en Segovia (España)

This article describes the work done on the Cardinal Diego de Espinosa Palace which consisted of injecting expanding polyurethane resin into the soil at different depths (Uretek Deep Injections) in order to mitigate the differential settlements detected in the structure. This injection technology has proven to be more effective than the more convention methods used in the past which consisted of raising the foundation by building concrete shafts, which did not manage to mitigate the causes of the pathologies observed in the palace