The paper gives a simplified model of flat panel with four sides fixed on a flexible foundation and analyzes the mechanic regularity of flat roof before the first falling.

给出弹性地基四边夹支平板简化模型，分析初次跨落前顶板的受力机理。

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His race came unstuck when he lost ground by running wide on the first lap before falling to the back of the field because of a gearbox problem.

BBC: Massa gains upper hand in Brazil

Pietersen made only two more runs after the first appeal before falling lbw to the fired-up Siddle but Prior went on to form a formidable partnership with Jonathan Trott as England finished the day on 444-5, 346 ahead of the hosts.

BBC: Ashes: Ricky Ponting fined by ICC after on-field row

The second half started slowly, the first real chance falling to Arfield just outside the Motherwell penalty area in the 58th minute and the midfielder's effort drifting wide of the mark.

BBC: Ryan Flynn