강관말뚝 지지력 평가에 관한 연구

Abstract

Based on the test rule, KS F 24455 and ASTM D 1143, this investigation test had been carried out to confirm the static compression load test for steel pipe pile(Ø508mm) foundation to the construction of work section 326 of Pusan subway construction, which falls on Area I for the investigation case and the bearing power in the axis direction for bridge piles to be used for the construction of road works between Deok-chun IC and Sam-rak IC, Da-Dae Port rear road, which falls on Area II for the investigation case. 1. As a result of the static compression load test, settlement of Test No. 1 at the design load stages(90tonf) was measured at 2.27mm and 1.33mm for Test No. 2, respectively for Area I of the investigation case and the settlement of Test No. 1 at the maximum test load stages(180tonf) was measured at 4.59mm and 2.71mm for Test No. 2, respectively. the settlement value at the maximum test load stages(550tonf) for Area II of the investigation case was 29.52mm. 2. After the load removed, remaining settlement of Area I of the research case was 1.31mm for Test No. 1 and 0.67mm for Test No. 2, respectively and 5.49mm for Area II of the investigation case. 3. In Area I of the investigation case, load-pile vertical displacement under the static compression load test was almost lineal with yielding load unconfirmed and as a result of assessing permitted bearing power, taking the test maximum load as the yielding load, sufficient safety rate is judged to be secured since the permitted bearing power under the maximum static compression load is assessed to be more than 90tonf/pile. 4. In view of the relations between the load and settlement being calculated in Area II of the research case, the graph of load-settlement has shown a tendency of straight line up to the loading of 300tonf but beginning from the loading, the settlement volume started to be increased and at 6 cycle 550tonf, the settlement around the pile head had been increased sharply and after passing 50 minutes from loading, pile bending started and load sustaining became impossible with the installed displacement scale dislocated, leading to load test close but it was found that this test met the design load requirements.