2018年7月26日,藤田公司发布消息,称该公司开发出了山岭隧道爆破降噪系统。该系统通过在隧道内外设置吸音板和扬声器,在开挖阶段可高效降低噪音和低频音。藤田公司在其施工的隧道现场中验证了该系统的应用效果,并表示,作为现场周边的环...2018年7月26日,藤田公司发布消息,称该公司开发出了山岭隧道爆破降噪系统。该系统通过在隧道内外设置吸音板和扬声器,在开挖阶段可高效降低噪音和低频音。藤田公司在其施工的隧道现场中验证了该系统的应用效果,并表示,作为现场周边的环境对策,将积极采用该降噪系统。爆破降噪系统由管单元消音器和主动标靶消音器组成。管单元消音器用于开挖的初期阶段,利用防水板铺设机在隧道内设置玻璃棉吸音板,对于人耳听到的噪音(频率100~500 Hz),具有降低4~6分贝的效果,由于不需要大型装置,平均每个施工现场投入80万日元左右的成本就能解决问题;主动标靶消音器是从扬声器发出逆相位音,旨在消除随着开挖的进行而传递到洞外的低频音(20~100 Hz),每台扬声器可将200 m 2范围内的噪音降低5~10分贝,如果增加扬声器的设置数量,将会获得更好的降噪效果,有助于抑制施工现场附近建筑物的振动状况。展开更多
It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape f...It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape function space is nothing but the Adini＇s element＇s, which has nothing to do with the other high degree terms and leads to a new method for constructing the high accuracy plate elements. This fact has never been seen for other conventional and unconventional, conforming and nonconforming rectangular plate elements, such as Quasi-conforming elements, generalized conforming elements and other double set parameter finite elements. Moreover, such kind of rectangular elements can not be constructed by the conventional finite element methods.展开更多
文摘2018年7月26日,藤田公司发布消息,称该公司开发出了山岭隧道爆破降噪系统。该系统通过在隧道内外设置吸音板和扬声器,在开挖阶段可高效降低噪音和低频音。藤田公司在其施工的隧道现场中验证了该系统的应用效果,并表示,作为现场周边的环境对策,将积极采用该降噪系统。爆破降噪系统由管单元消音器和主动标靶消音器组成。管单元消音器用于开挖的初期阶段,利用防水板铺设机在隧道内设置玻璃棉吸音板,对于人耳听到的噪音(频率100~500 Hz),具有降低4~6分贝的效果,由于不需要大型装置,平均每个施工现场投入80万日元左右的成本就能解决问题;主动标靶消音器是从扬声器发出逆相位音,旨在消除随着开挖的进行而传递到洞外的低频音(20~100 Hz),每台扬声器可将200 m 2范围内的噪音降低5~10分贝,如果增加扬声器的设置数量,将会获得更好的降噪效果,有助于抑制施工现场附近建筑物的振动状况。
文摘It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape function space is nothing but the Adini＇s element＇s, which has nothing to do with the other high degree terms and leads to a new method for constructing the high accuracy plate elements. This fact has never been seen for other conventional and unconventional, conforming and nonconforming rectangular plate elements, such as Quasi-conforming elements, generalized conforming elements and other double set parameter finite elements. Moreover, such kind of rectangular elements can not be constructed by the conventional finite element methods.
