TY - JOUR T1 - Assessment of Force-Deflection Relations of Steel Tubular Members under Lateral Quasi-Static Impacts from Dropped Objects TT - ارزیابی روابط نیرو-تغییرمکان اعضای لوله‌ای فولادی تحت ضربه جانبی شبه‌استاتیکی سقوط اجسام JF - Marine-Engineering JO - Marine-Engineering VL - 10 IS - 20 UR - http://marine-eng.ir/article-1-293-en.html Y1 - 2015 SP - 79 EP - 88 KW - Offshore pipeline KW - Force-Deflection KW - Dent KW - Indentor KW - Lateral Impact N2 - In the current study a numerical simulation approach has been chosen to simulate the force-deflection response of tubular member under lateral impact in the absence of internal pressure or axial force and the results have then been compared with analytical relations. Two series small scale experiments were carried out by the authors on X70 steel tubes and D/t of 22 and the numerical model has then been verified against experimental results. The results show that the analytical relations estimate greater lateral resistance than experimental results for the spherical indentor and in the unpressurized tubular members. The numerical model has then been used to study the effect of D/t and d/D and yield stress on lateral resistance of steel tubes. It has been noticed that, the lateral resistance was governed by: 1) D/t ratio 2) Yield stress 3) d/D ratio. The comparison between analytical and numerical results show that analytical relations are more accurate results for large D/t and d/D ratios. M3 ER -