吊杆索力的计算方法与应用研究

由于吊杆长度刚度、边界条件等因素对结构的影响程度不同,可得到频率法测吊杆力在不同假设下的四种计算模型。结合某140 m提篮式系杆拱桥,对四种模型进行了计算分析,与实测的数据进行对比,结果表明,在测试吊杆力时,系杆拱桥特别是短索的测试中必须考虑刚度以及边界条件的影响。     

沥青船船型特点及设计简介

沥青船作为一种特殊的船型,具有较高科技含量,制造难度较大。简要介绍了沥青船市场现状（包括运营沥青船的航运公司）、沥青船的设计技术水平现状、装载货物的性质、特征及规范对装载该类货种船舶的相应要求、不同液货舱型式（整体式和独立式）及其在结构支撑、定位止动和防浮、隔热绝缘方面的特点。船体线型、总体、结构和货物维护系统方面的特点及设计中需要特别注意的若干问题。     

美国光电侦察系统的发展动向与分析

光电侦察系统在现代战争中发挥着越来越重要的作用。文章介绍了国外光电侦察系统的发展历程以及装备的研制、改进情况,指出了在现代战争中发展光电侦察系统的优势和重要性,重点探讨了几种光电侦察系统的性能及其特点,最后论述了光电侦察系统的发展动向与分析。     

基于改进的Logvinovich法对带横摇运动非对称楔形体入水砰击力的计算(英文)

The water entry problem of an asymmetric wedge with roll motion was analyzed by the method of a modified Logvinovich model (MLM). The MLM is a kind of analytical model based on the Wagner method, which linearizes the free surface condition and body boundary condition. The difference is that the MLM applies a nonlinear Bernoulli equation to obtain pressure distribution, which has been proven to be helpful to enhance the accuracy of hydrodynamic loads. The Wagner condition in this paper was generalized to solve the problem of the water entry of a wedge body with rotational velocity. The comparison of wet width between the MLM and a fully nonlinear numerical approach was given, and they agree well with each other. The effect of angular velocity on the hydrodynamic loads of a wedge body was investigated.     

Truss Spar平台非线性垂荡-纵摇耦合随机运动分析(英文)

Considering the static stability and the change of the displacement volume, including the influences of higher order nonlinear terms and the instantaneous wave surface, the nonlinear coupled heave-pitch motion was established in stochastic waves. The responses of heave-pitch coupling motion for the Truss Spar platform were investigated. It was found that, when the characteristic frequency of a stochastic wave is close to the natural heave frequency, the large amplitude pitch motion is induced under the parametric-forced excitation, which is called the Mathieu instability. It was observed that the heave mode energy is transferred to pitch mode when the heave motion amplitude exceeds a certain extent. In addition, the probability of internal resonant heave-pitch motion is greatly reduced while the characteristic wave frequency is away from the natural heave frequency.     

舰机协同搜潜直升机编队配置优化研究

为增大直升机使用吊放声呐协同水面舰艇搜潜时的作战能力,对直升机编队参数进行优化配置。根据舰机协同搜潜行动的特点,给出了配置参数间的数学模型,以直升机悬停点间隔为主要因素,提出了编队对潜搜索效率的基本模型,计算了直升机编队协同搜潜时的最优配置参数和最大搜索效率。结果表明,在舰艇群队形一定时,直升机编队搜潜效率由配置参数确...     

高速破片侵彻防护液舱试验研究

为研究水下接触爆炸产生的高速破片在水中的侵彻特性,针对3.3 g立方体破片进行了水下弹道试验,结果表明:破片的侵彻阻力系数受形状的影响较大,撞击隔板时产生压缩波使破片产生墩粗和侵蚀,造成破片迎流面积的增加和质量的下降,从而使破片在速度较高时侵彻深度反而下降。     

浅析微表处在宣广高速路面养护中的应用

微表处技术在高速公路沥青路面养护中是一种功能完善、经济有效的预防性养护措施。该文以宣广高速沥青路面微表处在车辙处治方面的施工实践,介绍了微表处配合比的试验经验及施工的主要技术要求,供从事沥青路面养护施工的同行参考。     

PTC管桩在市政道路深层软土地基处理中的应用

PTC管桩处理路段在造价增加不多的情况下,获得了比水泥土搅拌桩和排水固结法更好的处理效果和质量可控性。该文通过工程实例,对PTC管桩设计进行了归纳与总结。     

新形势下高速公路养护技术的思考

阐述了科学发展观与高速公路养护工作的关系,介绍了高速公路预防性养护的主要方法,提出了用科学发展观"以人为本"、"全面、协调、可持续发展"的理念指导开展高速公路养护工作的思路。