泡沫轻质土的浸水性能试验研究

摘要

通过对湿密度400～1 000 kg/m3泡沫轻质土试样进行浸水、吸水和抗浮试验,研究了浸水条件下结构物所受浮力的变化规律和作为填充物时泡沫轻质土的抗浮能力与吸水能力.结果表明:当泡沫轻质土逐渐浸水至全部淹没,对上部结构产生的最大浮力与湿密度呈下开口的抛物线关系,当湿密度为700 kg/m3时浮力最大;泡沫轻质土逐渐吸水使自身密度增加,对上部结构产生的浮力逐渐减少;作为填充材料且上部无结构重物时,为使泡沫轻质土不产生上浮,初始浸水体积与总体积的比值应小于一定的限值,此限值与湿密度呈线性关系;设计时应充分考虑水的作用时间;底部接触水面时,泡沫轻质土会从底部吸水从而使自身质量增加,质量吸水率随湿密度增大而减小.%By immersion,water absorption and anti-flotation tests of foamed light soil samples whose wet density are 400 ～ 1 000 kg/m3,the buoyancy change rule of the samples under water immersion condition,the anti-floating capacity and water absorption capacity of the foamed light soil as filling material were studied.The results show that when the foamed light soil is immersed in water and gradually submerged,the relationship of maximum buoyancy on the upper structure and the wet density of the samples are parabolic with bottom open.The buoyancy is maximum while wet density is 700 kg/m3.The foamed light soil gradually absorbs water and its density increases with the time lasting,the buoyancy on the upper structure gradually decreases.As a filling material with no structural weight of the upper part,the ratio between initial water immersion volume and the total volume of the sample should be less than some limit values in order to avoid floating.The limit values have a linear relationship with the wet density of the samples.The time of water action should be fully considered in the design.The foamed light soil will absorb water and its mass will increase when the bottom contact the water and the mass water absorption decreases with the wet density increasing.