Stress-stabilized subisostatic fiber networks in a ropelike limit
Stress-stabilized subisostatic fiber networks in a ropelike limit
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DOI：
10.1103/physreve.99.042412
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发表时间：
2019-04-22
影响因子：
2.4
通讯作者：
MacKintosh, Fred C.
中科院分区：
文献类型：
--
作者：
Arzash, Sadjad;Shivers, Jordan L.;MacKintosh, Fred C.
无序的纤维网络的力学，如那些构成细胞外基质是强烈依赖于局部连接或配位数。对于生物聚合物网络，该配位数通常在3和4之间。这样的网络是亚均衡的，并且对只有中心力相互作用的变形是线性不稳定的，但是在应变下表现出在松弛状态和刚性状态之间的机械相变。弱弯曲相互作用的引入稳定了这些网络，并抑制了这种转变的关键特征。我们表明，施加外部应力也可以稳定亚均衡网络，只有拉伸中心力的相互作用，即，一种绳索般的潜力。此外，我们发现线性剪切模量与外部正应力呈幂律标度，具有非平均场指数。对于有限弯曲刚度的网络，我们发现临界应变移动到较低的预应力值。
The mechanics of disordered fibrous networks such as those that make up the extracellular matrix are strongly dependent on the local connectivity or coordination number. For biopolymer networks this coordination number is typically between 3 and 4. Such networks are sub-isostatic and linearly unstable to deformation with only central force interactions, but exhibit a mechanical phase transition between floppy and rigid states under strain. The introduction of weak bending interactions stabilizes these networks and suppresses the critical signatures of this transition. We show that applying external stress can also stabilize subisostatic networks with only tensile central force interactions, i.e., a ropelike potential. Moreover, we find that the linear shear modulus shows a power-law scaling with the external normal stress, with a non-mean-field exponent. For networks with finite bending rigidity, we find that the critical stain shifts to lower values under prestress.