Formwork for ventilated monolithic foundations www.geoplast.it TRADITIONAL FOUNDATION MOISTURE INSTABILITY CRACKS *WHAT IS RADON Radon is a colourless and extremely volatile gas produced by the decay of uranium U238. Radon gas occurs naturally, and is constantly produced by certain rocks in the Earth’s crust. The main source of Radon gas is the ground: it seeps through the soil and accumulates into rooms and enclosed places. It is very dangerous as it is carcinogenic: its prolonged inhalation is considered the second cause of lung cancer after cigarette smoke; the risk of cancer development is proportional to the exposure to radioactive gas. The only protection from Radon are ventilated foundations, which making it harmless dilute the gas into the atmosphere outside the building. The danger of RADON accumulation in a house built on traditional foundations. 2 FISSURES MONOLITHIC VENTILATED FOUNDATION MODULO SYSTEM CREATES MONOLITHIC VENTILATED FOUNDATIONS IN A SINGLE POUR
Modulo System, the combination of Modulo and Geoblock, makes it possible to pour the foundation and the groundslab in a single operation, creating a monolithic structure that won’t crack. A ventilated and monolithic foundation grants high stability and load-bearing capacity, significantly reducing the risks of damage in the case of earthquakes. STABILITY SINGLE POUR The soil is a heterogeneous blend of solid elements, water and air. Water is the element naturally most subject to fluctuations due to variable rainfall patterns, changes in water table level, evaporation and deep infiltration. Groundwater in direct contact with traditional foundations creates unhealthy conditions in the building: infiltrations, moisture, condensation and moulds and fungi; in extreme cases it can lead to the decay of timber structural elements. A ventilated foundation is the only solution for ground moisture VENTILATED FOUNDATIONS IN ROMAN TIMES Buildings with ventilated foundation are healthy an
d safe homes. The Romans understood that it was unhealthy to dwell in direct contact with the soil, so they elevated the floor of their homes to stop moisture and used the hollow space thus created to heat the rooms above. A ventilated foundation is an effective barrier to moisture and Radon, the dangerous and carcinogenic gas that accumulates inside buildings. MONOLITHIC STRUCTURE 3 DIFFERENT TYPES OF FOUNDATION › TRADITIONAL FOUNDATION When traditional foundations are made the slab and the ground beams are poured in two operations. The load is not well distributed over the slab, which leads to: MAX LOAD breaking point stress Radon gas moisture › CRACKS › MOISTURE › RADON GAS › TRADITIONAL MONOLITHIC FOUNDATION In a monolithic foundation load is evenly distributed and it remains below the admissible limit. Despite this, the contact between the foundation and the soil causes the rising of: STEEL STRESS reaction subsidence LOAD no breaking point MAX stress › MO
ISTURE › RADON GAS Even when load is well distributed, stress levels of the steel elements of the foundation are critically high. STEEL STRESS reaction › MODULO System: VENTILATED MONOLITHIC FOUNDATION A VENTILATED MONOLITHIC foundation is the solution that combines the advantages of a monobloc structure and a ventilated one. The load is distributed uniformly and remains under the breaking limit. The greater distance from the point of force application decreases steel and slab stress. › NO CRACKS ON STRUCTURAL FAILURES › NO STEEL STRESS › NO MOISTURE RISE › NO RADON GAS › VENTILATION OK LOAD MAX stress STEEL STRESS ventilation reaction 4 TYPE OF LOAD Overload kg/m2 Min. slab thickness cm Lean mix cm 0 Screed thickness cm Pressure on the soil mm kg/cm2 1.753 0.601 0.300 Rebar maglia cm 2,000 RESIDENTIAL 4 5 10 ø6 20 x 20 5 5,000 4 10 5 1.428 0.714 10 25 25 30 0.427 ø6 20 x 20 15,000 INDUSTRIAL 25,000 40,000 5 10 15 10 10 15 0.345 0.574 0.5
99 ø8 ø8 ø8 20 x 20 20 x 20 20 x 20 6 7 8 9 10 5 CONSTRUCTION CONTRACT - TECHNICAL SPECIFICATION Construct a sanitary void and the reinforced concrete groundslab above it by pouring concrete onto regenerated polypropylene (*) lost formwork type MODULO®, manfactured by Geoplast S.p.A., Italy; each MODULO® element has a square base of 50x50, 58x58 or 71x71 cm, with the shape of a dome or a series of domes, of height as required by the designer. The top surface of MODULO® is designed to correctly place the welded mesh and to support the pour of concrete min. resistance class Rck 250; the interconnected forms will create a series of domes and pillars in a bidirectional square matrix. The sanitary void created is suitable for the passage of services and/or the ventilation of the foundation. The sides will be blocked-off using the extensible elements type GEOBLOCK® which are designed to allow the single pour of foundation beams and groundslab. (*) Regenerated Polypropylene
(PP): Flexural modulus 1100 N/mm2 - Tensile strength 35 N/mm2 - Coefficient of thermal expansion 0.15 mm/m/°C. Execution: A) B) Pour a slab of lean concrete of the thickness specified by the project design. If required by the Project Management, holes for services shall be made and references shall be traced before the forms are put in place. C) Ventilation of the foundation is provided by openings of ø 80/120 mm every 3.50 / 4.00 m in the perimeter structures, connected to the sanitary void with PVC pipes. The openings shall be protected from pest intrusion by metal grids. To achieve best results the vents shall be placed at a higher level on the southern face of the building (warmer side) than on the norhtern face (colder side). Should groundbeams divide the groundslab in sectors, these should be interconnected by pipes. D) E) F) Install the elements type MODULO® and GEOBLOCK® in regenerated polypropylene as required by the project design. Place the reinforcement (welded mesh
) as required by the project design. Pour concrete of resistance class and performance in the amount required in order to fill the voids created by the forms, creating a series of pillars, and the top slab of the thickness required by the project design, with or without the aid of a concrete pump. G) Vibrate the concrete pour. All ancillary services and structures required for a workmanlike execution must be included. FOR OUR CUSTOMERS Our Technical Dept. is always available for design assistance, providing the solution that makes best use of the characteristics of Geoplast products. Send your project to: ufficiotecnico@geoplast.it Disclaimer: the values shown in this brochure are for guidance only. They are not meant to be used for design criteria. Their use and reliance thereon for any purpose by anyone is entirely voluntary and at the sole risk of the user. GEOPLAST is not responsible for any loss, claim, or damage resulting from their use. SERVICE CUSTOMER Example of a des
ign with CUSTOMER SERVICE: PROJECT DEVELOPMENT Send your projects in DWG format to ufficiotecnico@geoplast.it CERTIFICATION MODULO is a product certified by TEST REPORT 1019X/9/001 issued by TECHNOPROVE - Vicenza ASSEMBLY HANDBOOK AND TECHNICAL SPECIFICATIONS Available in our website www.geoplast.it in the “Area Download” section 11 12 MODULO System: TECHNOLOGY AT YOUR SERVICE 13 GEOPLAST S.p.A. 35010 Grantorto PD - Italia - Via Martiri della Libertà, 6/8 tel +39 049 9490289 - fax +39 049 9494028 e-mail: geoplast@geoplast.it - www.geoplast.it rev.002 ST. 10/2011
