武汉市高架桥走向和两边建筑高度对桥下日照的影响  

Influence of Viaduct Trend and Building Height on Sunlight under Viaduct in Wuhan City

作　　者：周平平[1] 李鹏 李旦[1] 徐永荣[1] ZHOU Ping-ping LI Peng LI Dan XU Yong-rong(Horticulture and Forestry Collage HZAU, Wuhan 430070, China Gardening Plant Institute of Wuhan City, Wuhan 430081,China)

机构地区：[1]华中农业大学园艺林学学院,武汉430070 [2]武汉市园林科学研究所,武汉430081

出　　处：《城市环境与城市生态》2016年第6期13-17,21,共6页Urban Environment & Urban Ecology

基　　金：武汉市园林科研项目(2011-67)

摘　　要：应用Sketch up软件模拟武汉市南北向和东西向高架桥日照时数分布以及两边建筑高度在夏至日对桥下日照时数的影响,并实测了3座高架桥下不同日照时数区域不同季节的光照强度。结果表明:(1)无建筑影响时,武汉市平均高度6.8 m、宽度24 m的高架桥下的日照时间分布为南北向高架桥下冬至日在6 h以下,春秋分日在7 h以下,夏至日在8h以下,均以4~6 h区域为主;东西向高架桥下冬至日和夏至日均在10 h以下,并以2 h以下为主,春秋分日有局部可达到全日照,但也存在大部分无日照区域。(2)夏至日两边建筑对武汉市高架桥下日照的影响非常显著,总体上随着建筑高度(0m^60 m)的增加,桥下日照时间迅速减少:南北向高架桥下无建筑时8 h>当建筑高度为10 m时6 h>当建筑高度为20m时5 h>当建筑高度为30 m时4 h>当建筑高度为40 m时3 h>当建筑高度为50 m时2 h。东西向高架桥下,无建筑时10 h>当建筑高度为10 m时8 h>当建筑高度为20 m时6 h,随后北侧日照时数随高度增加继续减少,但是南侧4~6 h日照区域基本不变。东西向高架桥下两边建筑高度达到20 m以上时,将出现大面积的无直射光区域,该区域面积超过70%。(3)实测武汉市3座高架桥下光照强度结果显示:无直射光区域常年相对照度均在30%以下,平均为21.2%;2 h以下日照区平均相对照度为35.6%;2~4 h区域为46.7%;4~6 h区域为61.3%;6~8 h区域为70.6%;8~10 h区域为75.7%。In order to understand the sunshine under a viaduct, sunshine durations of different trend and building height were simulated by sketch up in Wuhan City, and light duration was determined under 3 viaducts in different seasons. The results showed that without considering the influence of building, the sunshine durations under the S-N oriented viaduct with a height of 6.8 m and width of 24 m in Wuhan were 〈6 hours at winter solstice, 〈7 hours at vernal equinox and autumnal equinox and 〈8 hours at summer solstice, and 4-6 hours in most areas. The sunshine durations under the E-W oriented viaduct were 〈10 hours at summer solstice and winter solstice, and 〉2 hours in most areas. There was full illumination in a small area and no sunshine in most other areas at vernal and autumnal equinox. The sunshine durations at summer solstice under the viaduct decreased with increasing building height. The sunshine duration was 8 h without a building, 6 h in a 10 m building, 5 h in a 20 m building, 4 h in a 30 m building, 3 h in a 40 m building and 2 h in a 50 m building under the S-N viaduct. In contrast, the sunshine duration was 10 h without a building, 8 h in a 10 m building, 6 h in a 20 m building, and nil hour in 70% areas in a 20 m building under the E-W viaduct. The relative light intensity of 3 viaducts in Wuhan was 〈30% （average= 21.2% ） in areas without direct sunshine, 35.6% in areas with 〉2 h sunshine, 46.7% in areas with 2-4 h sunshine, 61.37% in areas with 4-6 h sunshine, 70.6% in areas with 6-8 h shine and 75.7% in areas with 8-10 h sunshine.

关 键 词：高架桥下 软件 建筑高度 日照时间 相对照度 武汉市 

分 类 号：S731.2[农业科学—林学]