已知梯形的上底和下底和高,坡比知道,求两边坡长,怎么算? 已知路中高程和路边高程和坡比计算边坡长度怎么计算?
\u8fb9\u5761\u5761\u6bd41:1.75\u6c42\u653e\u5761\u957f\u5ea6\u4e0e\u5bbd\u5ea6\u600e\u4e48\u7b97\u662f\u591a\u5c111\uff1a1.75\u5761\u6bd4\uff0c\u8fb9\u5761\u9ad8\u5dee1M\uff0c\u5bf9\u5e94\u7684\u8fb9\u5761\u6c34\u5e73\u5bbd\u5ea6\u589e\u52a01.75M\u3002\u6309\u6b64\u6bd4\u4f8b\u5173\u7cfb\u8ba1\u7b97\u5373\u53ef\u3002
\u4f8b\u5982\uff1a
\u5782\u76f4\u8ddd\u79bb\uff1a\u6c34\u5e73\u8ddd\u79bb=1:1.5
1.5\u5782\u76f4\u8ddd\u79bb=\u6c34\u5e73\u8ddd\u79bb
\u6c34\u5e73\u8ddd\u79bb=1.5\u00d73.2=4.8
\u659c\u957f=\u221a\uff083.2²+4.8²\uff09=5.76888
\u6269\u5c55\u8d44\u6599\uff1a
\u5761\u9762\u7684\u5782\u76f4\u9ad8\u5ea6(h)\u548c\u6c34\u5e73\u5bbd\u5ea6(l)\u7684\u6bd4\u53eb\u505a\u5761\u5ea6\uff08\u6216\u5761\u6bd4\uff09\u3002
\u5761\u9762\u4e0e\u6c34\u5e73\u9762\u7684\u5939\u89d2\u53eb\u505a\u5761\u89d2\uff0c\u4e00\u822c\u8bb0\u4f5c\u03b1\u3002
\u8bbe\u5761\u89d2\u4e3a\u03b1\uff0c\u5761\u5ea6\u4e3ak\uff0c\u5219k=h:l=tan\u03b1\uff1b
\u5761\u5ea6\u4e00\u822c\u5199\u62101\u2236m\u7684\u5f62\u5f0f\uff0c\u5176\u4e2dm=1/k\uff0cm\u79f0\u4e3a\u8fb9\u5761\u7cfb\u6570,
\u5761\u5ea6\u8d8a\u5927\uff0c\u5219\u5761\u89d2\u8d8a\u5927\uff0c\u5761\u9762\u5c31\u8d8a\u9661\uff0c\u59821\uff1a2>1\uff1a3\uff0c\u52191\uff1a2\u5bf9\u5e94\u7684\u5761\u89d2\u5927\uff0c\u5761\u9762\u8f83\u9661\u3002
1\uff1am\u53ef\u7406\u89e3\u4e3a\uff1a\u9ad8=1\uff0c\u5bbd=m\uff1b\u5373\u5761\u5ea6=tan\u03b1=h\uff1al=1\uff1am
\u53c2\u8003\u8d44\u6599\u6765\u6e90\uff1a\u767e\u5ea6\u767e\u79d1-\u5761\u6bd4
\u5761\u6bd4\u5373\u5761\u9762\u7684\u5782\u76f4\u9ad8\u5ea6h\u548c\u6c34\u5e73\u5bbd\u5ea6l\u7684\u6bd4\uff0c\u5373\u5761\u89d2\u7684\u6b63\u5207\u503c
(tan\u2220a\u503c\u2220a\u4e3a\u659c\u5761\u4e0e\u6c34\u5e73\u9762\u5939\u89d2)\u3002\u7406\u89e3\u4e86\u8fd9\u4e2a\u6982\u5ff5\u5c31\u597d\u7b97\u4e86\uff0c\u4f60\u8bf4\u7684\u8fb9\u5761\u957f\u5ea6\u5373\u6c34\u5e73\u5bbd\u5ea6\u4e3a\uff1a\u6c34\u5e73\u5bbd\u5ea6=\uff0894.197-85.87\uff09*1.5=12.4905
绛旓細涓婂簳x 锛屾尝姣旓細a=h/锛坉-x锛変唬鍏ユ暟鍊兼尝姣攁銆傞珮搴锛屼笅搴d 锛涜В鍑烘潵寰楀埌 x=d-h/a
绛旓細鍧″害tan鈭犖=0.52/{(1.1-0.5)/2}=26/15 鈭犖=arctan(26/15)=arctan1.73 澶ф鍏崄搴︺60掳
绛旓細鍧℃瘮,鍗冲潯闈㈢殑鍨傜洿楂樺害h鍜屾按骞冲搴鐨勬瘮,鍗冲潯瑙掔殑姝e垏鍊 鎵浠涓婂簳=1.2-2脳[(1.05脳0.5锛壝1]锛1.2-1.05锛0.15m
绛旓細鏍规嵁棰樻剰寰楀鍥撅細鈭燗=鈭燚=90掳锛孋D=2锛孉B=6锛岃繃C浣淐E鈯B浜嶦锛屽垯鍥涜竟褰ECD鏄煩褰紝鈭碅E=CD=2锛屸埓BE=AB-AE=4锛屽潯姣CE锛欱E=1锛2锛屸埓CE=2锛屽嵆楂樹负2銆
绛旓細宸茬煡锛屾褰㈤珮2.87绫筹紝涓婂簳杈归暱4绫锛屽潯姣涓1:2锛岋紙鍙湁涓涓潯姣旓紝鏄瓑鑵版褰級鏍规嵁鍧℃瘮鐨勫畾涔夛紝涓嬪簳杈规瘮涓婂簳杈归暱 2.87梅(1/2)脳2 = 11.48 绫筹紝鍙緱锛氫笅搴曡竟闀夸负 4+11.48 = 15.48 绫炽
绛旓細棣栧厛锛屽潯搴︽瘮鏄杈规瘮閭昏竟 鍥犱负鍧″害姣斾负1锛0.3 鎵浠ュ彲鐭ラ偦杈逛负锛3.35脳0.3=1.005绫 鑰涓婂簳涓0.5绫筹紝鍒涓嬪簳涓猴細0.5+1.005脳2=2.51绫
绛旓細鍦姊舰ABCD涓紝AD鈭C,AB=CD.涓嬪簳BC=50cm,BE鈯D浜嶦,BE=30cm,AB鐨勫潯搴︽瘮=BE/AE=1/1.5,鎵浠E=1.5BE=45cm,浜庢槸涓婂簳AD=BC+2AE=50+90=150cm.浠呬緵鍙傝冦
绛旓細鐢盇D锛欱E=鍧℃瘮=1锛0.3锛屽緱锛400锛欱E=1锛0.3锛孊E=120锛屼笂搴AD=BC-2BE=300-2脳120=60銆
绛旓細鍧″害姣鏄1:0.3 涔熷氨鏄瓑浜庨珮锛氾紙涓婁笅搴曞樊鐨勪竴鍗婏級鎵浠ヤ笂涓嬪簳鐨勫樊=0.3*楂
绛旓細鍥炵瓟锛氫緷棰樻剰,姹俠,宸茬煡h=2.5 a=0.2 鍧℃瘮=h/L=1/0.3,甯﹀叆h=2.5,鍙互寰桳=2.5*0.3/1=0.75,鑰宐=a+L,甯﹀叆a鍜孡鐨勫煎緱鍒癰=0.75+0.2=0.95