Name: setting out a horizontal curve
Uploaded: 2025-03-26T15:36:39.000Z
Duration: 1 min 3 s
Channel: JoVE

يبلغ نصف قطر المنحنى الأفقي 400 متر ، وزاوية التقاطع 30 درجة ، ومحطة نقطة الانحناء 0 + 150 مترا. الهدف هو تحديد محطات نقطة التقاطع ونقطة الظل ونقطة منتصف المنحنى ، وكذلك حساب طول الوتر الطويل. لتحديد المحطات ، يتم حساب مسافة الظل وطول المنحنى أولا باستخدام نصف القطر وزاوية تقاطع المنحنى. تعطى محطة نقطة التقاطع بإضافة طول المماس إلى المحطة عند نقطة الانحناء. يتم حساب محطة نقطة الظل بإضافة طول المنحنى إلى المحطة عند نقطة الانحناء. أخيرا ، يتم العثور على محطة نقطة المنتصف بإضافة نصف طول المنحنى إلى محطة نقطة الانحناء.  ثم يتم الحصول على طول الوتر الطويل من خلال التعبير المقابل.

المنحنى الأفقي: حل المشكلات

يتميز المنحنى الأفقي بنصف قطره وزاوية التقاطع ووضع النقاط الرئيسية. في هذه الحالة ، يبلغ نصف القطر 400 متر ، وزاوية التقاطع 30 درجة ، مع محطة نقطة الانحناء (PC) عند 0 + 150 مترا. الهدف هو تحديد قيم المحطة عند نقطة التقاطع (PI) ، ونقطة الظل (PT) ، ونقطة منتصف المنحنى ، بالإضافة إلى طول الوتر الطويل. تبدأ العملية بحساب مسافة الظل (T) وطول المنحنى (L). تعتمد مسافة الظل على نصف القطر وظل نصف زاوية التقاطع. يعتمد طول المنحنى على نصف القطر وزاوية التقاطع المحولة إلى راديان. يتم العثور على محطة PI بإضافة مسافة الظل إلى محطة PC، ومحطة P.T. يتم تحديدها بإضافة طول المنحنى إلى محطة PC. يتم حساب محطة نقطة منتصف المنحنى بإضافة نصف طول المنحنى إلى محطة PC يتم اشتقاق طول الوتر الطويل ، الذي يمتد على المنحنى مباشرة بين PC. و PT ، باستخدام العلاقات المثلثية التي تتضمن نصف القطر وزاوية التقاطع. تضمن هذه الحسابات التثبيت الدقيق وسلامة التصميم في تحديد المنحنيات الأفقية البسيطة.

A horizontal curve is characterized by its radius, intersection angle, and stationing of key points. In this case, the radius is 400 meters, and the angle ...

Education

JoVE Core

Civil Engineering

الهندسة المدنية

Unit 1

الوحدة الأولى

Horizontal and Vertical Curves

المنحنيات الأفقية والرأسية

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الرئيسية

Horizontal Curve: Problem Solving

setting out a horizontal curve

A horizontal curve is set out by using its radius, intersection angle, and stationing of key points. In this example, the radius is 400 meters, the intersection angle is 30 degrees, and the station of the point of curvature, or P.C., is 0 + 150 meters. The goal is to find the station values for the point of intersection, or P.I., the point of tangency, or P.T., and the midpoint of the curve. The length of the long chord is also needed.

The first step is to calculate the tangent distance, T, and the curve length, L. Tangent distance depends on the radius and the tangent of half the intersection angle. Curve length depends on the radius and the intersection angle written in radians. These values are used to place the curve correctly in station form.

Next, the station of the P.I. is found by adding the tangent distance to the station of the P.C. The station of the P.T. is found by adding the curve length to the station of the P.C. The station of the midpoint of the curve is the P.C. station plus half of the curve length. The long chord, which stretches directly from the P.C. to the P.T., is found with trigonometric relationships that use the radius and the intersection angle. These calculations support accurate design and setting out of simple horizontal curves.

Setting Out a Horizontal Curve

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horizontal curve: problem solving

A horizontal curve is set out by using its radius, intersection angle, and stationing of key points. In this example, the radius is 400 meters, the intersection angle is 30 degrees, and the station of the point of curvature, or P.C., is 0 + 150 meters. The goal is to find the station values for the point of intersection, or P.I., the point of tangency, or P.T., and the midpoint of the curve. The length of the long chord is also needed. The first step is to calculate the tangent distance, T,...

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key terms and concepts

Find the P.I., P.T., midpoint, and long chord for a horizontal curve using radius, intersection angle, and stationing from the point of curvature.

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civil engineering

Setting Out a Horizontal Curve

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