عنوان مقاله :
مطالعه ي آزمايشگاهي ظرفيت باربري و نشست پي هاي دايرهاي لبه دار واقع بر روي ماسه
عنوان به زبان ديگر :
EXPERIMENTAL STUDY OF THE BEARING CAPACITY AND SETTLEMENT CIRCULAR SKIRTED FOUNDATIONS RESTING ON THE SAND
پديد آورندگان :
قلي پور، سجاد دانشگاه بوعلي سينا - دانشكده مهندسي، همدان , مكارچيان، مسعود دانشگاه بوعلي سينا - دانشكده مهندسي، همدان
كليدواژه :
پيهاي لبهدار , ظرفيت باربري , نشست , چگالي نسبي , مدلسازي فيزيكي
چكيده فارسي :
پيهاي لبهدار قابليت استفاده بهعنوان يك نوع پي جديد براي جايگزيني پيهاي سطحي، شامل: پيهاي مخازن نفت و گاز، توربينهاي بادي، سكوهاي حفاري نفتي و نيز پيهاي نيمهعميق و عميق را دارند. رفتار پيهاي لبهدار جهت مطالعهي عملكردشان از نظر ظرفيت باربري و نشست در مقايسه با پيهاي سطحي متداول، توسط مدلسازي فيزيكي پي دايرهيي لبهدار بر روي ماسه در آزمايشگاه بررسي شد. پارامترهايي شامل: طول لبه، اندازهي فونداسيون، چگالي نسبي ماسه و زبري سطح فونداسيون و لبه در پژوهش حاضر مطالعه شدند. نتايج آزمايشها بهبود كلي در عملكرد پيهاي لبهدار را نسبت به پيهاي سطحي نشان داد. نسبت ظرفيت باربري پيهاي لبهدار به پيهاي سطحي، افزايش حدود 2٫3 تا 5 برابر را نشان داد و همچنين مقدار نشست پي لبهدار تا حدود 8% نشست پي سطحي كاهش داشت. نمودارهايي جهت تخمين مقادير افزايش ظرفيت باربري و كاهش نشست پيهاي لبهدار در نوشتار حاضر ارائه شده است.
چكيده لاتين :
The skirted foundations can be considered to be as new foundation options of shallow foundations including oil and gas storage tanks, wind turbines, oil drilling platforms, and also pier and deep foundations. Skirted foundations are steel or concrete foundations, which have a top raft and a relatively thin plate beneath the periphery, the so-called skirt. The skirts penetrate into the soil beneath foundation and form an enclosure in which soil is extremely confined. The skirts and confined soil behave as a unit to shift loads to the soil at the level of skirt tip. The benefit of skirted foundations over conventional foundations lies in their ease and short time of installations. To study the skirted foundations behavior and comparison with common shallow foundations in terms of the bearing capacity and settlement, laboratory tests were carried out on circular skirted foundation resting on sand layer using physical modeling. In this study, parameters such as ratio of skirt depth to foundation diameter, foundation size, the relative density of sand, and roughness of skirt surface were investigated. The test results showed the overall improvement of skirted foundations performance compared to surface foundations. The enhancement in the bearing capacity as well as reduction in the settlement of shallow foundation increases with increasing skirt depth and decreasing relative density of sand. Bearing capacity ratio of skirted foundations to surface foundations increased about 2.3 to 5 times. In addition, the settlement value of skirted foundation decreased up to 8% of that a surface foundation. In this paper, based on the obtained results, charts are presented to estimate bearing capacity enhancement and settlement reduction in terms of sand relative density, skirt depth to foundation diameter ratio and roughness. Skirted foundations resting on loose sand are more beneficial than those resting on medium and dense sand.
عنوان نشريه :
مهندسي عمران شريف
عنوان نشريه :
مهندسي عمران شريف