河南省延津县是地处豫北黄河故道的古老县城。该县房管所管理的3万多平方米的公房,多是解放前后修建的简陋平房,还有少部分房屋建于清末。砌体用砖多为手工烧结蓝砖。这些砖由于外现尺寸与现行机砖模数不同,强度又低于100号, Yanjin County, Henan Province is an ancient county located in the old course of the Yellow River in northern Henan. More than 30,000 square meters of public houses managed by the county housing administration are mostly simple bungalows built before and after liberation, and a small number of houses were built in the late Qing Dynasty. Masonry bricks are mostly hand-sintered blue bricks. These bricks have a strength of less than 100 due to the difference in size between the current size and the current number of bricks.