紙(zhi)面穿(chuan)孔石(shi)膏板常用(yong)(yong)于建筑裝飾吸聲(sheng)。紙(zhi)面石(shi)膏板本身并不具有良好的(de)吸聲(sheng)性能(neng)(neng)，但穿(chuan)孔后并安裝成帶有一定后空腔的(de)吊頂或貼(tie)面墻則可形成“亥(hai)姆霍茲共振”吸聲(sheng)結構(gou)，因而獲得較大的(de)吸聲(sheng)能(neng)(neng)力。這種紙(zhi)面穿(chuan)孔吸聲(sheng)結構(gou)廣泛地應用(yong)(yong)于廳堂音質及吸聲(sheng)降噪等聲(sheng)學工程中(zhong)。

石(shi)(shi)膏(gao)板(ban)(ban)穿(chuan)孔(kong)(kong)后(hou)，石(shi)(shi)膏(gao)板(ban)(ban)上(shang)的(de)小孔(kong)(kong)與(yu)石(shi)(shi)膏(gao)板(ban)(ban)自身及原(yuan)(yuan)建筑結構(gou)的(de)面(mian)層(ceng)形(xing)成了共(gong)振(zhen)(zhen)腔體，聲(sheng)音與(yu)穿(chuan)孔(kong)(kong)石(shi)(shi)膏(gao)板(ban)(ban)發生作用后(hou)，圓孔(kong)(kong)處的(de)空(kong)氣柱產生強烈(lie)的(de)共(gong)振(zhen)(zhen)，空(kong)氣分子與(yu)石(shi)(shi)膏(gao)板(ban)(ban)孔(kong)(kong)壁劇烈(lie)摩(mo)擦，從而大量地消耗聲(sheng)音能量，進行(xing)吸(xi)(xi)聲(sheng)。這是穿(chuan)孔(kong)(kong)紙(zhi)(zhi)(zhi)面(mian)石(shi)(shi)膏(gao)板(ban)(ban)“亥姆(mu)霍茲共(gong)振(zhen)(zhen)”吸(xi)(xi)聲(sheng)的(de)基本原(yuan)(yuan)理(li)。穿(chuan)孔(kong)(kong)紙(zhi)(zhi)(zhi)面(mian)石(shi)(shi)膏(gao)板(ban)(ban)吸(xi)(xi)聲(sheng)對聲(sheng)音頻(pin)率(lv)(lv)(lv)(lv)具有一(yi)定選(xuan)擇(ze)性，吸(xi)(xi)聲(sheng)頻(pin)率(lv)(lv)(lv)(lv)特性曲線呈山峰形(xing)，當聲(sheng)音頻(pin)率(lv)(lv)(lv)(lv)與(yu)共(gong)振(zhen)(zhen)頻(pin)率(lv)(lv)(lv)(lv)接(jie)近時，吸(xi)(xi)聲(sheng)系(xi)數(shu)大；當聲(sheng)音頻(pin)率(lv)(lv)(lv)(lv)遠(yuan)離共(gong)振(zhen)(zhen)頻(pin)率(lv)(lv)(lv)(lv)時，吸(xi)(xi)聲(sheng)系(xi)數(shu)小。如果在紙(zhi)(zhi)(zhi)面(mian)穿(chuan)孔(kong)(kong)石(shi)(shi)膏(gao)板(ban)(ban)背覆一(yi)層(ceng)桑皮(pi)紙(zhi)(zhi)(zhi)或(huo)薄(bo)吸(xi)(xi)聲(sheng)氈時，空(kong)氣分子在共(gong)振(zhen)(zhen)時的(de)摩(mo)擦阻力增(zeng)大，各個頻(pin)率(lv)(lv)(lv)(lv)的(de)吸(xi)(xi)聲(sheng)性能都將有明顯提高，這就是人們常常在穿(chuan)孔(kong)(kong)紙(zhi)(zhi)(zhi)面(mian)石(shi)(shi)膏(gao)板(ban)(ban)后(hou)覆一(yi)層(ceng)桑皮(pi)紙(zhi)(zhi)(zhi)或(huo)薄(bo)吸(xi)(xi)聲(sheng)氈增(zeng)加吸(xi)(xi)聲(sheng)的(de)原(yuan)(yuan)因(yin)。

影(ying)響(xiang)紙(zhi)面穿(chuan)孔石膏板(ban)吸(xi)聲(sheng)性能(neng)的(de)(de)(de)主(zhu)要因素是(shi)穿(chuan)孔率(lv)和(he)后空(kong)(kong)腔(qiang)大(da)小，穿(chuan)孔孔徑、石膏板(ban)的(de)(de)(de)厚度等對(dui)吸(xi)聲(sheng)性能(neng)影(ying)響(xiang)較(jiao)小。穿(chuan)孔率(lv)從(cong)2%到15%之(zhi)間逐漸增(zeng)大(da)時(shi)，孔占(zhan)的(de)(de)(de)表面積增(zeng)大(da)，空(kong)(kong)氣分子進入共振腔(qiang)體參(can)與共振的(de)(de)(de)幾率(lv)增(zeng)加，吸(xi)聲(sheng)能(neng)力(li)增(zeng)大(da)，若(ruo)后空(kong)(kong)腔(qiang)內放入吸(xi)聲(sheng)材料(liao)，吸(xi)聲(sheng)更強烈。穿(chuan)孔率(lv)會影(ying)響(xiang)共振頻率(lv)，穿(chuan)孔率(lv)增(zeng)大(da)，共振頻率(lv)將向高頻偏移(yi)，偏移(yi)量與穿(chuan)孔率(lv)的(de)(de)(de)開根號成正(zheng)比。穿(chuan)孔率(lv)增(zeng)大(da)，吸(xi)聲(sheng)頻率(lv)特(te)性曲線(xian)的(de)(de)(de)“山峰”將向右側（高頻）移(yi)動，且“山峰”形(xing)態整體趨于抬高，平(ping)均(jun)吸(xi)聲(sheng)系(xi)數增(zeng)加。增(zeng)大(da)穿(chuan)孔率(lv)可以提(ti)高吸(xi)聲(sheng)性能(neng)，但因石膏板(ban)強度的(de)(de)(de)限(xian)制，一(yi)般穿(chuan)孔率(lv)在2%-15%的(de)(de)(de)范圍(wei)。

當后(hou)(hou)空(kong)(kong)(kong)(kong)(kong)腔(qiang)增大時(shi)，共振(zhen)腔(qiang)內的(de)空(kong)(kong)(kong)(kong)(kong)氣(qi)分子數量(liang)增多(duo)，共振(zhen)時(shi)參與消耗聲(sheng)能(neng)的(de)空(kong)(kong)(kong)(kong)(kong)氣(qi)分子數增多(duo)，吸聲(sheng)性能(neng)增加。改變后(hou)(hou)空(kong)(kong)(kong)(kong)(kong)腔(qiang)大小(xiao)是常用的(de)調節(jie)穿孔石膏板吸聲(sheng)系(xi)(xi)數的(de)方(fang)法。后(hou)(hou)空(kong)(kong)(kong)(kong)(kong)腔(qiang)大小(xiao)會影(ying)響共振(zhen)頻率(lv)，空(kong)(kong)(kong)(kong)(kong)腔(qiang)增大，共振(zhen)頻率(lv)將向低頻偏移(yi)(yi)，偏移(yi)(yi)量(liang)與空(kong)(kong)(kong)(kong)(kong)腔(qiang)深(shen)度的(de)開根號成反比(bi)，吸聲(sheng)頻率(lv)特性曲線的(de)“山峰”將向左（低頻）移(yi)(yi)動，“山峰”形態(tai)整體(ti)趨于(yu)抬高(gao)，平均吸聲(sheng)系(xi)(xi)數變大。但當空(kong)(kong)(kong)(kong)(kong)腔(qiang)深(shen)度過大時(shi)，空(kong)(kong)(kong)(kong)(kong)腔(qiang)內“空(kong)(kong)(kong)(kong)(kong)氣(qi)彈簧”效果減弱，吸聲(sheng)性能(neng)下降，一般(ban)情況空(kong)(kong)(kong)(kong)(kong)腔(qiang)深(shen)度在(zai)5-50cm以內為宜。　　

在通(tong)常(chang)范圍內(nei)，穿孔(kong)孔(kong)徑(jing)大小(xiao)一(yi)(yi)般是3-10mm，石膏板厚(hou)(hou)度(du)(du)(du)一(yi)(yi)般是9.5mm、12mm或(huo)15mm，這些因素較(jiao)多(duo)地影響(xiang)(xiang)(xiang)共(gong)振頻(pin)(pin)率(lv)的(de)(de)高低，對(dui)穿孔(kong)紙面石膏板平(ping)(ping)均(jun)(jun)吸(xi)(xi)聲(sheng)性能(neng)的(de)(de)影響(xiang)(xiang)(xiang)很小(xiao)。孔(kong)徑(jing)增大或(huo)厚(hou)(hou)度(du)(du)(du)增加，共(gong)振頻(pin)(pin)率(lv)將(jiang)向低頻(pin)(pin)偏(pian)移(yi)(yi)，偏(pian)移(yi)(yi)量(liang)與孔(kong)徑(jing)或(huo)厚(hou)(hou)度(du)(du)(du)的(de)(de)開根(gen)號成反比，吸(xi)(xi)聲(sheng)頻(pin)(pin)率(lv)特性曲線(xian)的(de)(de)“山峰”將(jiang)向左（低頻(pin)(pin)）移(yi)(yi)動，“山峰”形態(tai)基本保持不變，因此平(ping)(ping)均(jun)(jun)吸(xi)(xi)聲(sheng)系數(shu)基本不變。根(gen)據實驗，孔(kong)徑(jing)大小(xiao)或(huo)石膏板厚(hou)(hou)度(du)(du)(du)的(de)(de)改變，平(ping)(ping)均(jun)(jun)吸(xi)(xi)聲(sheng)系數(shu)基本無(wu)大的(de)(de)變化，一(yi)(yi)般在10%以內(nei)，共(gong)振頻(pin)(pin)率(lv)的(de)(de)改變也(ye)只在一(yi)(yi)到兩個(ge)1/3倍(bei)頻(pin)(pin)程(cheng)的(de)(de)范圍內(nei)。在降噪實際工程(cheng)中孔(kong)徑(jing)和(he)板厚(hou)(hou)的(de)(de)選取(qu)主要(yao)根(gen)據應用場合(he)所需的(de)(de)強度(du)(du)(du)確定，孔(kong)徑(jing)選3-10mm，板厚(hou)(hou)選9-15mm均(jun)(jun)可，不同的(de)(de)板厚(hou)(hou)或(huo)孔(kong)徑(jing)基本可以忽略對(dui)吸(xi)(xi)聲(sheng)性能(neng)的(de)(de)影響(xiang)(xiang)(xiang)。

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